Patent Application
20240162528
This application relates to the field of battery technologies, and in particular, to a battery module and a transportation means equipped with the battery module.
Due to characteristics of flexibility, reliability, and high energy density in use of a battery module, the battery module has developed rapidly on both a power generation side and a power demand side, and an installed capacity has also increased significantly. Especially in the field of electric vehicles, there is a strong demand for chemical batteries represented by a lithium-ion battery. This brings rapid development of the battery module.
However, to control a volume of a product such as an electric vehicle and pursue a greater energy storage capacity, heat dissipation space of the battery module is inevitably compressed. Electrochemical cells inside the battery module are usually stacked. Thermal cascade effect inevitably exists, causing an excessively great temperature difference between the electrochemical cells. After the battery module works for a long time, a state of health (SOH) of a high-temperature electrochemical cell is obviously different from a state of health of a low-temperature electrochemical cell. The energy storage capacity of the battery module is restricted by an electrochemical cell with a lowest state of health. A decrease in an available capacity of the electrochemical cell causes a decrease in an overall energy storage capacity of the battery module. As a result, a battery life of a product such as an electric vehicle equipped with the battery module may decrease relatively quickly.
In view of disadvantages of conventional technologies, an objective of the present disclosure is to provide a battery module capable of maintaining a temperature difference between electrochemical cells, and a transportation means equipped with the battery module. This application specifically includes the following technical solutions:
A battery module includes a case, a first electrochemical cell layer, a second electrochemical cell layer, a middle separator, and an air supply unit. The first electrochemical cell layer, the middle separator, and the second electrochemical cell layer are stacked and fastened in the case. The middle separator is located between the first electrochemical cell layer and the second electrochemical cell layer. The middle separator includes a first side edge and a second side edge. Both the first side edge and the second side edge extend along a first direction. A main air duct, a first secondary air duct, and a second secondary air duct are further disposed in the middle separator. The main air duct penetrates the middle separator along the first direction. The first secondary air duct is communicated with the main air duct. Another end of the first secondary air duct extends to the first side edge. The second secondary air duct is communicated with the main air duct. Another end of the second secondary air duct extends to the second side edge.
A first ventilation hole and a second ventilation hole are disposed on the case. The first ventilation hole and the second ventilation hole are respectively located on two sides of the middle separator and are arranged in the first direction. The air supply unit is connected to the case in a fastened manner, and is configured to exhaust air in the middle separator out of the case through the first ventilation hole.
In the battery module of this application, the first electrochemical cell layer and the second electrochemical cell layer are accommodated and fastened through the case. The middle separator is fastened between the first electrochemical cell layer and the second electrochemical cell layer. Through the main air duct, the first secondary air duct, and the second secondary air duct disposed in the middle separator, ventilation and heat dissipation may be separately performed on the first electrochemical cell layer and the second electrochemical cell layer. The first ventilation hole and the second ventilation hole are separately disposed on the case, and the first ventilation hole and the second ventilation hole are respectively arranged on the two sides of the middle separator along the first direction. Therefore, air can be taken from different directions through the main air duct, the first secondary air duct, and the second secondary air duct of the middle separator, and the air supply unit exhausts air in the middle separator out of the case through the first ventilation hole.
In this way, when air cooling is performed on the first electrochemical cell layer and the second electrochemical cell layer, air may be taken from three different directions through the middle separator in the battery module in this application. The air in the first secondary air duct and the second secondary air duct may supplement the air in the main air duct, to avoid an undesirable phenomenon that heat dissipation effect gradually decreases due to a gradual increase of an air temperature in a flowing process of air along a single path. In addition, when the cooling air flows through the first secondary air duct and the second secondary air duct, heat dissipation and cooling are further performed for regions corresponding to the first secondary air duct and the second secondary air duct. In this way, cooling effect is more uniformly implemented for the first electrochemical cell layer and the second electrochemical cell layer, and a phenomenon that an overall energy storage capacity of the battery module is reduced due to thermal cascade effect can be avoided, thereby prolonging a service life of the battery module.
In one embodiment, the case includes an air intake board, an air exhaust panel, a first side board, and a second side board. The air intake board and the air exhaust panel are respectively arranged on the two sides of the middle separator along the first direction. The first ventilation hole is located on the air exhaust panel. The first side board and the second side board are separately connected between the air intake board and the air exhaust panel. The first side board is located on a side that is of the first side edge and that is away from the main air duct. The second side board is located on a side that is of the second side edge and that is away from the main air duct.
In this embodiment, the case is formed by using the air intake board, the air exhaust panel, the first side board, and the second side board in an enclosed manner, and may accommodate the first electrochemical cell layer, the second electrochemical cell layer, and the middle separator. In addition, the first ventilation hole is disposed on the air exhaust panel. The air supply unit can supply air to the first ventilation hole. Therefore, after entering the case from the second ventilation hole, the cooling air flows through the middle separator at least in a direction of the main air duct, and then flows out of the case from the second ventilation hole. Correspondingly, the second ventilation hole is located on the air intake board, and air outside the air intake board may be supplemented into the case through the second ventilation hole.
In one embodiment, there are a plurality of main air ducts. The plurality of main air ducts are arranged in the middle separator along a second direction. The second direction is perpendicular to the first direction.
In this embodiment, the plurality of main air ducts are disposed and extend side by side, to increase a cooling area of the middle separator for the first electrochemical cell layer and the second electrochemical cell layer, thereby implementing better cooling effect.
In one embodiment, there are a plurality of first secondary air ducts. The plurality of first secondary air ducts are spaced along the first direction. There are also a plurality of second secondary air ducts. The plurality of second secondary air ducts are also spaced along the first direction.
In this embodiment, the plurality of first secondary air ducts and the plurality of second secondary air ducts are disposed, to increase an air intake volume of the two opposite sides of the middle separator. Therefore, more air at the two opposite sides of the middle separator can enter the main air duct, to supplement air in the main air duct and reduce a temperature of air for cooling in the main air duct.
In one embodiment, the first secondary air duct includes a first strong secondary air duct and a first weak secondary air duct. The first strong secondary air duct is located between the first weak secondary air duct and the air exhaust panel. A quantity of main air ducts communicated with the first strong secondary air duct is greater than or equal to a quantity of main air ducts communicated with the first weak secondary air duct.
The second secondary air duct includes a second strong secondary air duct and a second weak secondary air duct. The second strong secondary air duct is located between the second weak secondary air duct and the air exhaust panel. A quantity of main air ducts communicated with the second strong secondary air duct is greater than or equal to a quantity of main air ducts communicated with the second weak secondary air duct.
In this embodiment, the first strong secondary air duct and the first weak secondary air duct are disposed, and the quantity of the main air ducts communicated with the first strong secondary air duct is greater than or equal to the quantity of the main air ducts communicated with the first weak secondary air duct. Therefore, in an extension direction of the main air duct, more air is introduced in a direction of the first side edge at a location closer to the air exhaust panel. Because the air temperature in the main air duct gradually increases with the extension of the flow path, through the disposition in this embodiment, more low-temperature air can be introduced at a location with a higher air temperature in the main air duct, to supplement air for heat dissipation in the main air duct, thereby improving heat dissipation efficiency of the middle separator. Correspondingly, the second strong secondary air duct and the second weak secondary air duct are disposed in the second secondary air duct, to implement similar effect.
In one embodiment, a distance between first secondary air ducts located close to an air exhaust side edge is greater than a distance between first secondary air ducts located away from the air exhaust side edge; and a distance between second secondary air ducts located close to the air exhaust side edge is greater than a distance between second secondary air ducts located far away from the air exhaust side edge.
In this embodiment, the distance between the first secondary air ducts and the distance between the second secondary air ducts are set to enhance heat dissipation effect for an electrochemical cell unit in a middle part of the electrochemical cell layer, so that heat dissipation effect tends to be consistent for electrochemical cell units in the electrochemical cell layer.
In one embodiment, at least one main air duct is disposed between the first secondary air duct and the second secondary air duct.
In this embodiment, through the foregoing disposition, it can be ensured that at least one main air duct is neither communicated with the first secondary air duct, nor communicated with the second secondary air duct. In this way, the air flowing along a path of the main air duct may flow out of the middle separator through the at least one main air duct, and flow out of the case through an air exhaust window. Through such a disposition, the following defect can be avoided: An air flow in the main air duct is excessively small because a lateral air flow generated by using the first secondary air duct and/or the second secondary air duct hinders flow of the air in the main air duct.
In one embodiment, a first section is disposed on the first side edge. The first section is located on a side that is of the first side edge and that is close to the air exhaust panel. The first secondary air duct is located in the first section. A length h1 of the first section along the first direction and a length H1 of the first side edge meet a condition that h1 is less than or equal to 3/4 H1. A second section is disposed on the second side edge. The second section is located on a side that is of the second side edge and that is close to the air exhaust panel. The second secondary air duct is located in the second section. A length h2 of the second section along the first direction and a length H2 of the second side edge meet a condition that h2 is less than or equal to 3/4H2.
In this embodiment, the first section and the second section are separately disposed on a side farther from the air intake board, so that when the air in the main air duct initially enters the middle separator, the air is not affected by the air in the first secondary air duct and the air in the second secondary air duct. Because an initial temperature of the air in the main air duct is relatively low, and the flow path is relatively short, better heat dissipation effect can be implemented by using the first secondary air duct and the second secondary air duct without intervention.
In one embodiment, the main air duct includes an upper main air duct and a lower main air duct. An opening facing the first electrochemical cell layer is disposed on the upper main air duct. An opening facing the second electrochemical cell layer is disposed on the lower main air duct. At least one lower main air duct is disposed between two upper main air ducts.
In this embodiment, the upper main air duct and the lower main air duct are disposed, to implement better cooling effect for the first electrochemical cell layer by using the upper main air duct and better cooling effect for the second electrochemical cell layer by using the lower main air duct. However, at least one lower main air duct is disposed between the two upper main air ducts, so that the upper main air duct and the lower main air duct can be disposed in a cross manner, and cooling effect can be more uniformly implemented for the first electrochemical cell layer and the second electrochemical cell layer by using the main air duct.
In one embodiment, the first secondary air duct has a first air intake end and a first air exhaust end that are opposite to each other. The first air intake end is communicated with the first side edge. The first air exhaust end is communicated with the main air duct. A projection of the first air exhaust end on the first side edge is located between the first air intake end and the air exhaust panel.
The second secondary air duct has a second air intake end and a second air exhaust end that are opposite to each other. The second air intake end is communicated with the second side edge. The second air exhaust end is communicated with the main air duct. A projection of the second air exhaust end on the second side edge is located between the second air intake end and the air exhaust panel.
In this embodiment, the first air exhaust end of the first secondary air duct is closer to the air exhaust panel than the first air intake end, or the first air exhaust end and the first air intake end are aligned, so that a maximum turning angle of a flow path of air from the first secondary air duct to the main air duct is kept within 90 degrees, thereby facilitating flow of air in the first secondary air duct. Correspondingly, the second air exhaust end of the second secondary air duct is also closer to the air exhaust panel than the second air intake end, and similar effect can also be achieved.
In one embodiment, limiting boards are further disposed on the first side edge and the second side edge of the middle separator. The limiting boards extend in opposite directions perpendicular to a plane of the middle separator, to limit a relative location between each electrochemical cell layer and the middle separator.
In this embodiment, the limiting board may protrude from a location of a side wall of each electrochemical cell layer, and is configured to limit displacement of each electrochemical cell layer relative to the middle separator.
In one embodiment, limiting sub-boards are further disposed on the middle separator. The limiting sub-boards are spaced along both the first side edge and the second side edge. The limiting sub-board is configured to limit a relative location between the electrochemical cell unit in each electrochemical cell layer and the middle separator.
In this embodiment, the limiting sub-boards may be spaced along a length direction of the first side edge and a length direction of the second side edge, and are configured to limit displacement of each electrochemical cell unit relative to the middle separator.
In one embodiment, a plurality of notches are disposed on the limiting board. The plurality of notches are configured to form the first air intake end of the first secondary air duct and the second air intake end of the second secondary air duct.
In one embodiment, the middle separator includes a base board and air guide strips. The air guide strips protrude from the base board, and are configured to form the main air duct together with the base board in an enclosed manner.
In one embodiment, the air guide strips are located on the two opposite sides of the middle separator, and separately protrude from the base board. The air guide strip on one side and the base board form the upper main air duct in the enclosed manner. The air guide strip on the other side and the base board form the lower main air duct in the enclosed manner.
In this embodiment, in a manner in which the air guide strips cooperate with the base board, relative locations of the upper main air duct and the lower main air duct may be adjusted. In some implementations, the upper main air duct and the lower main air duct may be alternatively symmetrically disposed relative to the base board.
In one embodiment, the first secondary air duct includes a first upper secondary air duct and a first lower secondary air duct. The first secondary air duct and the first secondary air duct are respectively arranged on an upper side and a lower side of the base board. The second secondary air duct includes a second upper secondary air duct and a second lower secondary air duct. The second upper secondary air duct and the second lower secondary air duct are respectively arranged on the upper side and the lower side of the base board.
In one embodiment, the electrochemical cell units in the electrochemical cell layer are arranged in a single column.
In one embodiment, the electrochemical cell units in the electrochemical cell layer are arranged in two columns, and two electrochemical cell units side by side are disposed opposite to each other.
In this embodiment, a positive electrode and a negative electrode of each electrochemical cell unit are located on a same side. A positive electrode and a negative electrode of each of the two electrochemical cell units that are arranged opposite to each other may be exposed at a surface of a side that is of the electrochemical cell unit and that is away from the other electrochemical cell unit.
In one embodiment, the middle separator includes a first support strip, a second support strip, and two third support strips. The first support strip is located on the first side edge. The second support strip is located on the second side edge. The two third support strips are located between the first side edge and the second side edge.
In this embodiment, the first support strip, the second support strip, and the third support strips are jointly configured to be attached to and support the electrochemical cell layers located on the upper side and the lower side of the middle separator. The third support strip close to the first side edge cooperates with the first support strip to support the electrochemical cell units on one side. The third support strip close to the second side edge cooperates with the second support strip to support the electrochemical cell units on the other side.
In one embodiment, there are three limiting boards in the middle separator. Two of the limiting boards are respectively located on the first side edge and the second side edge. The third limiting board is located at a middle part between the two limiting boards.
In this embodiment, corresponding to a structure in which the electrochemical cell layer includes two rows of electrochemical cell units, added limiting boards may be configured to limit a relative location between the two rows of electrochemical cell units.
In one embodiment, a plurality of limiting sub-boards are further spaced at the limiting board located in the middle of the middle separator. The limiting sub-boards are disposed in pairs. Limiting sub-boards in each pair are respectively located on two opposite sides of the limiting board.
In this embodiment, the limiting sub-boards located in the middle of the middle separator cooperate with limiting sub-boards located on the first side edge and the second side edge, and are configured to separately limit a relative location between two electrochemical cell units that are arranged side by side.
In one embodiment, a busbar is configured to connect the electrochemical cell units on a same side in series. The busbar includes a short busbar and a long busbar. The short busbar and the long busbar are respectively located at a head end and a tail end of a series circuit.
In one embodiment, the short busbar includes a first power connection pin, and the long busbar includes a second power connection pin. The first power connection pin and the second power connection pin are respectively bent relative to the short busbar and the long busbar, and are both located on one side of each electrochemical cell layer.
In this embodiment, the first power connection pin and the second power connection pin are disposed. This helps implement a series connection between the electrochemical cell units on the two sides, and implement an electrical connection between an electrochemical cell module and an external circuit.
In one embodiment, a third ventilation hole is further disposed on each of the first side board and the second side board.
In this embodiment, the third ventilation hole is disposed on each of the first side board and the second side board, so that air can be taken from the outside of the case close to each of the first secondary air duct and the second secondary air duct through each of the first secondary air duct and the second secondary air duct of the middle separator, thereby shortening a flow path for external cooling air to enter the middle separator and improving heat dissipation effect of the middle separator.
In one embodiment, the second ventilation hole is disposed at a location corresponding to the middle separator. The third ventilation hole is disposed at a location corresponding to each of the first secondary air duct and the second secondary air duct.
In this embodiment, the second ventilation hole is disposed at the location corresponding to the middle separator, so that air outside the case can enter the main air duct through the second ventilation hole. The third ventilation hole is disposed at the location corresponding to each of the first secondary air duct and the second secondary air duct, to facilitate air outside the case to enter the first secondary air duct and the second secondary air duct through the third ventilation holes.
In one embodiment, the case further includes an air exhaust board. The air exhaust board is located between the middle separator and the air exhaust panel. A main air exhaust hole is further disposed on the air exhaust board.
In this embodiment, the air exhaust board may enclose relatively sealed space with the air intake board, the first side board, and the second side board, so that heat dissipation is mainly implemented through the main air exhaust hole for the first electrochemical cell layer and the second electrochemical cell layer that are located in the relatively sealed space, thereby improving the heat dissipation effect of the middle separator.
In one embodiment, the main air exhaust hole is disposed at a location corresponding to the middle separator.
In this embodiment, the main air exhaust hole is disposed at the location corresponding to the middle separator, to facilitate cooling air in the case to flow out from the main air exhaust hole.
In one embodiment, the air supply unit is disposed in the case, and is located between the air exhaust board and the air exhaust panel.
In this embodiment, the air supply unit is disposed between the air exhaust board and the air exhaust panel, so that the air supply unit can also be accommodated in the case, and the case provides reliable protection for the air supply unit.
In one embodiment, the case further includes a top assembly and a bottom assembly. The top assembly is located on a side that is of the first electrochemical cell layer and that is away from the middle separator. The bottom assembly is located on a side that is of the second electrochemical cell layer and that is away from the middle separator. Both the top assembly and the bottom assembly are connected between the air intake board and the air exhaust board. In this embodiment, the top assembly and the bottom assembly are disposed along a stacking direction of the first electrochemical cell layer and the second electrochemical cell layer, to reliably protect the first electrochemical cell layer and the second electrochemical cell layer in a direction perpendicular to the middle separator. In addition, sealing performance of the case is improved.
In one embodiment, a top air flow channel is disposed in the top assembly, and a bottom air flow channel is disposed in the bottom assembly. Both the top air flow channel and the bottom air flow channel extend along the first direction. Secondary ventilation holes corresponding to the top air flow channel and the bottom air flow channel are further disposed on the air intake board. Secondary air exhaust holes corresponding to the top air flow channel and the bottom air flow channel are further disposed on the air exhaust board.
In this embodiment, heat dissipation is implemented for the first electrochemical cell layer and the second electrochemical cell layer respectively through the top air flow channel and the bottom air flow channel, so that cooling air flows through two opposite planes of the first electrochemical cell layer and the second electrochemical cell layer, thereby improving heat dissipation effect for the battery module in this application.
In one embodiment, an electrochemical cell assembly includes an upper separator and a lower separator. The upper separator is located between the electrochemical cell layer and the top assembly, to form a gap for ventilation and heat dissipation between the top assembly and the electrochemical cell layer. The lower separator is located between the electrochemical cell layer and the bottom assembly, to form a gap for ventilation and heat dissipation between the bottom assembly and the electrochemical cell layer.
In one embodiment, a sum of areas of the secondary ventilation holes is less than a sum of areas of the second ventilation holes; and/or a sum of areas of the secondary air exhaust holes is less than a sum of areas of the main air exhaust holes.
In this embodiment, the secondary ventilation holes are configured to implement cooling air flow in the top air flow channel and the bottom air flow channel. When the sum of the areas of the secondary ventilation holes is less than the sum of the areas of the second ventilation holes, or the sum of the areas of the secondary air exhaust holes is less than the sum of the areas of the main air exhaust holes, cooling air flow of a main channel in the middle separator is greater than both the air flow of the top air flow channel and air flow of the bottom air flow channel. Because the middle separator dissipates heat for both the first electrochemical cell layer and the second electrochemical cell layer, the air flow in the middle separator is set to be greater than the air flow of the top air flow channel and the air flow of the bottom air flow channel. It may be ensured that a temperature difference between the two opposite planes of the first electrochemical cell layer and the second electrochemical cell layer is smaller. In other words, it may be ensured that heat dissipation effect for the two opposite planes of the first electrochemical cell layer and the second electrochemical cell layer tend to be consistent.
In one embodiment, the battery module further includes a first insulation cover and a second insulation cover. The first insulation cover is located between the middle separator and the first side board. A first through hole corresponding to the first secondary air duct is further disposed on the first insulation cover.
The second insulation cover is located between the middle separator and the second side board. A second through hole corresponding to the second secondary air duct is further disposed on the second insulation cover.
In this embodiment, the first insulation cover and the second insulation cover work together to implement insulation between the busbar and each of the first electrochemical cell layer and the second electrochemical cell layer. The first through hole and the second through hole are respectively formed on the first insulation cover and the second insulation cover, so that air outside the third ventilation holes can enter the first secondary air duct and the second secondary air duct respectively through the first through hole and the second through hole.
In one embodiment, the first insulation cover includes a first outer surface facing the first side board. A first air guide groove is disposed on the first outer surface. One end of the first air guide groove is communicated with the first through hole. The other end of the first air guide groove is communicated with the air exhaust board.
The second insulation cover includes a second outer surface facing the second side board. A second air guide groove is disposed on the second outer surface. One end of the second air guide groove is communicated with the second through hole. The other end of the second air guide groove is communicated with the air exhaust board.
Air guide holes respectively corresponding to the first air guide groove and the second air guide groove are further disposed on the air exhaust board.
In this embodiment, the first air guide groove is formed on the first outer surface of the first insulation cover, so that part of air entering the case from the outside of the first side board can also flow along the first air guide groove, thereby implementing cooling heat dissipation for the busbar. Correspondingly, part of air entering the case from the outside of the second side board can also flow in the second air guide groove, thereby implementing cooling heat dissipation for the busbar.
In one embodiment, the battery module further includes a cavity and a control panel. The control panel is accommodated in the cavity. An air inlet and an air outlet are further disposed on the cavity. The air inlet is communicated with the main air duct, or the first air guide groove, or the second air guide groove. The air outlet is communicated with the air exhaust window of the air exhaust panel.
In this embodiment, the control panel is configured to control work of the first electrochemical cell layer and the second electrochemical cell layer, and is accommodated in the cavity and protected by the cavity. When the cavity is communicated with the main air duct, or the first air guide groove, or the second air guide groove, cooling air may further flow through the cavity, to implement heat dissipation for the control panel.
In one embodiment, the control panel is used as a battery management system, and/or an optimizer, and/or a direct-current conversion apparatus of the battery module.
In one embodiment, there are a plurality of control panels.
In one embodiment, there are two control panels. The two control panels are respectively arranged on two sides of the air supply unit.
In one embodiment, the air supply unit includes a first fan and at least two second fans. In the stacking direction of the first electrochemical cell layer and the second electrochemical cell layer, the first fan is located between the two second fans. When the air supply unit works, air exhaust power of the first fan is greater than air exhaust power of the second fans.
In this embodiment, functions of the air supply unit are implemented through an arrangement manner in which the first fan is located between the two second fans, so that a heat dissipation requirement of the battery module in this application can be met. The air exhaust power of the first fan is set to be higher. It may be ensured that air exhaust power at the location of the middle separator is higher than air exhaust power of the top air flow channel and air exhaust power of the bottom air flow channel. In this way, the following effect can also be achieved: The temperature difference between the two opposite planes of the first electrochemical cell layer and the second electrochemical cell layer is smaller, and it is ensured that the heat dissipation effect tends to be consistent for the two opposite planes of the first electrochemical cell layer and the second electrochemical cell layer.
In one embodiment, the air supply unit includes a third fan and a fourth fan. The third fan and the fourth fan are arranged side by side along the stacking direction of the first electrochemical cell layer and the second electrochemical cell layer. A first temperature sensor and a second temperature sensor are further disposed on the battery module. The first temperature sensor is configured to monitor a temperature of the first electrochemical cell layer. The second temperature sensor is configured to monitor a temperature of the second electrochemical cell layer. The control panel further receives temperature data obtained by the first temperature sensor and the second temperature sensor through monitoring, to separately control rotational speeds of the third fan and the fourth fan.
In this embodiment, a temperature difference may be formed between the first electrochemical cell layer and the second electrochemical cell layer. The control panel may monitor the temperature difference in real time through monitoring performed by the first temperature sensor and the second temperature sensor. Then, the control panel adjusts the rotational speeds of the third fan and the fourth fan, so that the control panel can adjust real-time heat dissipation power of the first electrochemical cell layer and the second electrochemical cell layer, thereby reducing the temperature difference between the first electrochemical cell layer and the second electrochemical cell layer and making the temperatures of the first electrochemical cell layer and the second electrochemical cell layer tend to be consistent.
This application further relates to a transportation means equipped with the foregoing battery module. It may be understood that because heat dissipation effect is more uniformly implemented for the battery module, a temperature difference between electrochemical cells in the battery module is controlled, so that an overall energy storage capacity of the battery module is better maintained. Therefore, a service life of the transportation means in this application is further prolonged.
In one embodiment, the transportation means is an electric vehicle or a hybrid vehicle.
In this embodiment, the battery module may provide the electric vehicle or the hybrid vehicle with electric energy needed for travel. Therefore, under a condition that carbon emission of the transportation means is reduced, an endurance mileage of the electric vehicle or the hybrid vehicle is better maintained, and a service life of the electric vehicle or the hybrid vehicle is prolonged.
In one embodiment, the transportation means further includes a vehicle frame, a power apparatus, a transmission apparatus, and a plurality of wheels. The battery module is accommodated in the vehicle frame, and electrically connected to the power apparatus. The power apparatus is in a transmission connection with each wheel through the transmission apparatus, converts electric energy stored in the battery module into rotation power, and transfers the rotation power to each wheel end through the transmission apparatus.
In this embodiment, the battery module provides the power apparatus with electric energy needed for working. The power apparatus converts the electric energy into the rotation power to output, and transfers the rotation power to each wheel end through the transmission apparatus, to drive the transportation means to travel on a road.
The following describes the technical solutions in embodiments of this application with reference to the accompanying drawings in embodiments of this application. It is clear that the described embodiments are merely some but not all of embodiments of this application. All other embodiments obtained by a person of ordinary skill in the art based on embodiments of this application without creative efforts shall fall within the protection scope of this application.
Refer to a battery module 100 shown in
In a schematic diagram of
Refer to a schematic exploded view of the battery module 100 according to this application shown in
Through-hole structures are disposed on each of the air intake board 31, the air exhaust panel 37, the first side board 33, and the second side board 34: a plurality of main ventilation holes 381 disposed on the air intake board 31, the air exhaust window 371 on the air exhaust panel 37, and the side ventilation holes 382 disposed on each of the first side board 33 and the second side board in some embodiments. The main ventilation holes 381 are understood as second ventilation holes. An air supply unit 50 (with reference to
In the schematic diagram of
The second support frame 44 is located between the second side board 34 and the electrochemical cell assembly 10. The second support frame 44 is separately connected to the top assembly 35 and the bottom assembly 36 in a fastened manner, and is configured to support the top assembly 35 and the bottom assembly 36. In addition, the second support frame 44 may be configured to tighten the electrochemical cell assembly 10. The second side board 34 is connected to the second support frame 44 in a fastened manner, to implement fastened connections relative to the top assembly 35 and the bottom assembly 36. It may be understood that, in some other embodiments, the second side board 34 may be alternatively directly connected to the top assembly 35 and the bottom assembly 36 in a fastened manner. The second insulation cover 42 is located between the second support frame 44 and the second side board 34. A plurality of busbars 45 are disposed between the second insulation cover 42 and the second side board 34. Each busbar 45 is in contact with and connected to the electrochemical cell assembly 10, to implement an electrical connection between the electrochemical cell layers in the electrochemical cell assembly 10 on a side close to the second side board 34. The first insulation cover 41 and the second insulation cover 42 jointly work to implement a function of insulation between the electrochemical cell assembly 10 and each busbar 45. It may be understood that, in some embodiments, an insulation separator 46 may be further disposed between each busbar 45 and the second side board 34, to prevent a current on the busbars 45 from being conducted to the second side board 34.
Refer to a schematic exploded view of the electrochemical cell assembly 10 shown in
In the schematic diagram of
It can be learned from
In some other embodiments, the positive electrodes 151 of several electrochemical cell units 15 and the negative electrodes of several electrochemical cell units 15 may be alternatively disposed on a same side of the electrochemical cell assembly 10. For example, the positive electrode 151 of each electrochemical cell unit 15 in the first electrochemical cell layer 11 is connected to the busbar 45 on the first insulation cover 41 side in a fastened manner, and the negative electrode of each electrochemical cell unit 15 in the second electrochemical cell layer 12 is connected to the busbar 45 on the first insulation cover 41 side in a fastened manner. The foregoing embodiments are all implementations that may be used by the battery module 100 in this application.
Overall dimensions of the middle separator 20 are approximately the same as overall dimensions of the first electrochemical cell layer 11. To be specific, when the middle separator 20 is sandwiched between the first electrochemical cell layer 11 and the second electrochemical cell layer 12, the middle separator 20 may roughly cover a surface that is of the first electrochemical cell layer 11 and that is in contact with the middle separator 20, and also roughly cover a surface that is of the second electrochemical cell layer 12 and that is in contact with the middle separator 20. In the first electrochemical cell layer 11, the plurality of electrochemical cell units 15 are arranged along the first direction 001, and a length of the overall first electrochemical cell layer 11 along the first direction 001 is greater than a length of the electrochemical cell unit 15. Therefore, a length direction of the middle separator 20 is also set along the first direction 001, namely, the arrangement direction of the plurality of electrochemical cell units 15.
Refer to a schematic diagram of a structure of the middle separator 20 shown in
The middle separator 20 further includes a first side edge 201, a second side edge 202, an air intake side edge 203, and an air exhaust side edge 204. Both the first side edge 201 and the second side edge 202 extend along the first direction 001. Both the air intake side edge 203 and the air exhaust side edge 204 extend along the second direction 002. To be specific, the first side edge 201 and the second side edge 202 are disposed opposite to each other along the second direction 002. In addition, the air intake side edge 203 and the air exhaust side edge 204 are disposed opposite to each other along the first direction 001.
A main air duct 23, a first secondary air duct 21, and a second secondary air duct 22 are further disposed in the middle separator 20. The main air duct 23 penetrates the middle separator 20 along the first direction 001. To be specific, the main air duct 23 includes a main air intake end 231 and a main air exhaust end 232 that are opposite to each other. The main air intake end 231 and the main air exhaust end 232 are disposed opposite to each other along the first direction 001. The main air intake end 231 is communicated with the air intake side edge 203. The main air exhaust end 232 is communicated with the air exhaust side edge 204.
In this way, an air flow channel may be formed in the main air duct 23. After entering the main air duct 23 from the main air intake end 231, cooling air may flow along the main air duct 23 and flow out of the middle separator 20 from the main air exhaust end 232. In a working process of the battery module 100 in this application, the electrochemical cell assembly 10 generates heat, thereby increasing a temperature of the middle separator 20. The flow of the outside cooling air in the main air duct 23 may take away high-temperature air at the middle separator 20, thereby reducing the overall temperature of the middle separator 20. It may be understood that the middle separator 20 with a reduced temperature may implement heat dissipation for the first electrochemical cell layer 11 and the second electrochemical cell layer 12 respectively through the first plane 205 and the second plane 206.
In the embodiments shown in
In a schematic diagram of
The opening 235 is disposed, so that cooling air in the main air duct 23 can directly act on outer surfaces of the first electrochemical cell layer 11 and the second electrochemical cell layer 12. To be specific, cooling air flowing in the upper main air duct 233 may act on the outer surface of the first electrochemical cell layer 11, and cooling air flowing in the lower main air duct 234 may also act on the outer surface of the second electrochemical cell layer 12. Cooling air may directly take away high-temperature air on the outer surfaces of the first electrochemical cell layer 11 and the second electrochemical cell layer 12 from the middle separator 20, so that the middle separator 20 has better cooling effect on the first electrochemical cell layer 11 and the second electrochemical cell layer 12 after the opening 235 is disposed.
In the schematic diagram of
Refer to a schematic diagram of a structure in another observation direction of the middle separator 20 shown in
Refer to a heat dissipation mode shown in
The foregoing phenomenon is referred to as thermal cascade effect.
Therefore, refer to a schematic diagram shown in
In this way, in this application, the first secondary air duct 21 and the second secondary air duct 22 are disposed, so that the middle separator 20 can be used to make the temperature of air flowing in the main air duct 23 to be kept within a relatively low range. In the conventional technologies, there is a greater temperature difference between the electrochemical cell 1 and the electrochemical cell 3 due to better cooling effect for the electrochemical cell 1 close to an air duct inlet. In comparison with this phenomenon, in this application, a temperature of the electrochemical cell 15 on a side close to the air exhaust side edge 204 in the battery module 100 can be closer to a temperature of the electrochemical cell 15 on a side close to the air intake side edge 203. In other words, cooling effect for the electrochemical cell units 15 in the battery module 100 in this application tends to be more consistent, and a temperature difference between the electrochemical cell units 15 in the working process is correspondingly smaller. In this way, according to the battery module 100 in this application, a temperature difference between different electrochemical cell units 15 is further reduced. Overall temperature consistency is maintained for the electrochemical cell assembly 10, so that a service life of the battery module 100 in this application is prolonged.
It may be understood that the battery module 100 in this application may be used in a transportation means 200 in this application. As shown in
In a schematic diagram of
It should be pointed out that, corresponding to an embodiment in which no side ventilation hole 382 is disposed on the first side board 33 and the second side board 34, cooling air in the case 30 mainly enters from the main ventilation hole 381 on the air intake board 31. In this case, air entering the case 30 may also enter the middle separator 20 separately through the main air duct 23, the first secondary air duct 21, and the second secondary air duct 22, to implement a heat dissipation function of the middle separator 20 for each electrochemical cell layer.
In the foregoing figure, there are a plurality of first secondary air ducts 21, and the plurality of first secondary air ducts 21 are spaced along the first direction 001; and there are also a plurality of second secondary air ducts 22, and the plurality of second secondary air ducts 22 are also spaced along the first direction 001. It may be understood that the plurality of first secondary air ducts 21 and the plurality of second air ducts 22 are disposed, to increase an air intake volume of the two opposite sides of the middle separator 20. Therefore, more cooling air outside the first side edge 201 and the second side edge 202 can enter the main air duct 23, to further decrease the temperature of air in the main air duct 23 and effectively supplement cooling air flowing in the main air duct 23.
Refer to a schematic diagram of the middle separator 20 shown in
With reference to
For cooling air flowing along the path of the main air duct 23, the temperature of cooling air gradually increases as the flow path extends. To be specific, in the main air duct 23, the temperature of cooling air closer to the air exhaust side edge 204 is higher, and the temperature of cooling air closer to the air intake side edge 203 is lower. Therefore, in the middle separator 20 in this application, the side close to the air exhaust side edge 204 has a lower requirement for cooling air than the side close to the air intake side edge 203. A greater quantity of main air ducts 23 communicated with the first strong secondary air duct 21a close to the air exhaust side edge 204 indicates more cooling air flowing into the main air duct 23 through the first strong secondary air duct 21a, so that a higher requirement of the region for cooling air is met. More cooling air flows into the first strong secondary air duct 21a, to effectively supplement inherent cooling air in the main air duct 23 and reduce the overall temperature of cooling air on the side close to the air exhaust side edge 204. The first weak secondary air duct 21b is closer to the air intake side edge 203, and a temperature increase of cooling air inherent in the main air duct 23 is relatively small. Therefore, the first weak secondary air duct 21b has a lower requirement for cooling air. The first weak secondary air duct 21b only needs to be communicated with a relatively small quantity of main air ducts 23 to meet a heat dissipation requirement.
It should be pointed out that, in the middle separator 20 in this application, when there are a plurality of first secondary air ducts 21, strong and weak secondary air ducts are defined only in a relative relationship. To be specific, for any two first secondary air ducts 21, when one first secondary air duct 21 is closer to the air exhaust side edge 204 than the other first secondary air duct 21, the first secondary air duct 21 closer to the air exhaust side edge 204 may be considered as a strong secondary air duct, and the other first secondary air duct 21 is considered as a weak secondary air duct.
For example, a first secondary air duct 21c shown in
Correspondingly, the second secondary air duct 22 may also include a second strong secondary air duct 22a and a second weak secondary air duct 22b. The second strong secondary air duct 22a is also located between the second weak secondary air duct 22b and the air exhaust side edge 204. In addition, a quantity of main air ducts 23 communicated with the second strong secondary air duct 22a is greater than or equal to a quantity of main air ducts 23 communicated with the second weak secondary air duct 22b. In addition, strong and weak secondary air ducts in the second secondary air duct 22 are also in a relative relationship. The second secondary air duct 22c shown in
Still with reference to
Similar to a principle of disposing the strong and weak secondary air ducts, when cooling air enters the middle separator 20 from the air intake side edge 203, an initial temperature of cooling air is relatively low, and a requirement for cooling air introduced from the first side edge 201 and the second side edge 202 is correspondingly low. Therefore, the first secondary air duct 21 and the second secondary air duct 22 do not need to be disposed on the side close to the air intake side edge 203, and a heat dissipation requirement for the region can be met. However, after cooling air in the main air duct 23 flows for a section of the path, the temperature of cooling air gradually increases. In this case, the first secondary air duct 21 and the second secondary air duct 22 are introduced to supplement the inherent cooling air in the main air duct 23, to ensure that the overall temperature of cooling air in the main air duct 23 tends to be consistent. Therefore, the first section 2011 and the second section 2021 are respectively disposed at locations that are relatively away from the air intake side edge 203. The plurality of first secondary air ducts 21 and the plurality of second secondary air ducts 22 are respectively disposed in the first section 2011 and the second section 2021. This helps maintain temperature consistency of cooling air in the main air duct 23. Therefore, it is ensured that heat dissipation effect tends to be consistent for the electrochemical cell units 15 in the first electrochemical cell layer 11 and the second electrochemical cell layer 12, and a temperature difference between the electrochemical cell units 15 is correspondingly reduced.
In one embodiment, at least one main air duct 23 is disposed between the first secondary air duct 21 and the second secondary air duct 22. As shown in
However, if there is no main air duct 23 disposed between the first secondary air duct 21 and the second secondary air duct 22, the first secondary air duct 21 is directly communicated with the second secondary air duct 22. In this case, an air flow path penetrating the middle separator 20 is formed along the second direction 002. Due to this part of flow path, a flow cut-off phenomenon occurs for the inherent cooling air flowing in all the main air ducts 23. As a result, the inherent cooling air in the main air ducts 23 cannot smoothly flow out of the middle separator 20 from the air exhaust side edge 204. This may lead to a phenomenon that the cooling air flowing into the main air ducts 23 is reduced, and heat dissipation effect is reduced for the electrochemical cell unit 15 on the side close to the air intake side edge 203. However, at least one main air duct 23 is still disposed between the first secondary air duct 21 communicated with the largest quantity of main air ducts 23 and the second secondary air duct 22 communicated with the largest quantity of main air ducts 23. Therefore, by using the at least one main air duct 23, it may be ensured that the inherent cooling air in at least some of the main air ducts 23 can smoothly flow out of the middle separator 20 from the air exhaust side edge 204. Correspondingly, the cooling air flowing into the main air ducts 23 from the air intake side edge 203 increases, thereby ensuring cooling effect for the electrochemical cell unit 15 in the region.
Refer to a partial schematic diagram shown in
Correspondingly, for the second air intake end 221 and the second air exhaust end 222 of the second secondary air duct, the following needs to be met: A projection of the second air exhaust end 222 on the second side edge 202 is located between the second air intake end 221 and the air exhaust side edge 204. The cooling air that enters the main air duct 23 from the second secondary air duct 21 can also continue to flow along the main air duct 23 more smoothly.
The limiting boards 207 respectively extend in directions of a first plane 205 and a second plane 206, and form limiting structures at the first side edge 201 and the second side edge 202 of the middle separator 20. It may be understood that, because the first side edge 201 and the second side edge 202 are arranged along the second direction 002, when each electrochemical cell layer is attached to and fastened to the middle separator 20, the limiting boards 207 may protrude from a side wall of each electrochemical cell layer, and is configured to limit displacement of each electrochemical cell layer relative to the middle separator 20 in the second direction 002.
Further, a plurality of limiting sub-boards 207a are further disposed at the locations of the first side edge 201 and the second side edge 202 of the middle separator 20. The limiting sub-boards 207a are spaced along an arrangement direction of the electrochemical cells 15 in the electrochemical cell layer (namely, the first direction 001), and extend from the limiting boards 207 towards a center of the middle separator 20. A distance between two adjacent limiting sub-boards 207a matches overall dimensions of a single electrochemical cell unit 15, so that the single electrochemical cell unit 15 can be inserted into a gap between the two adjacent limiting sub-boards 207a (as shown in
To be specific, in this embodiment, the middle separator 20 may limit the electrochemical cell layers to which the middle separator 20 is attached and fastened through cooperation of the limiting boards 207 and the limiting sub-boards 207a, and may maintain a relative distance between the electrochemical cell units 15 in the electrochemical cell layers. In this way, in a process of moving with the transportation means 200, for each electrochemical cell unit 15, a fixed relative location can be maintained, and a fixed location relative to the middle separator 20 can be maintained, so that heat dissipation effect for each electrochemical cell unit 15 is ensured.
Further with reference to
The lower air guide strip 252 extends from the base board 24 along the third direction 003. An extension direction of the lower air guide strip 252 is opposite to an extension direction of the upper air guide strip 251. There are also a plurality of lower air guide strips 252. The plurality of lower air guide strips 252 are spaced and disposed along the second direction 002. Surfaces that are of the plurality of lower air guide strips 252 and that are away from the base board 24 form a second plane 206 of the middle separator 20. The lower air guide strip 252 is further in a long strip shape along the first direction 001 on the middle separator 20. One lower main air duct 233 may be formed between two adjacent lower air guide strips 252.
In a schematic diagram of
Refer back to the schematic diagrams in
In an embodiment, for the middle separator 20 that uses the base board 24, the first secondary air duct 21 and the second secondary air duct 22 may be alternatively disposed in a manner of the foregoing strong and weak air ducts. To be specific, the first secondary air duct 21 and the second secondary air duct 22 shown in
Correspondingly, compared with the second secondary air duct 22 shown in
In a schematic diagram of
In some other embodiments, the control unit 60 may be alternatively used as an optimizer and/or a direct-current conversion apparatus of the battery module 100. When the control unit 60 is used as an optimizer of the battery module 100, the control unit 60 may switch the battery module 100 to a short-circuit state when a fault occurs in some or all of the electrochemical cell units 15 in the battery module 100, to prevent the battery module 100 from affecting overall work of the transportation means. When the control unit 60 is used as a direct-current conversion apparatus of the battery module 100, the control unit 60 is configured to implement a direct-current conversion function of the battery module 100.
As shown in
In some embodiments, as shown in
It may be understood that the plurality of control panels 61 of the control unit 60 may be separately configured to implement a function of the control unit 60. The function includes but is not limited to the foregoing battery management system, optimizer, and direct-current conversion apparatus. In some embodiments, two or more functions of the control unit 60 may be integrated on a same control panel 61, to implement comprehensive control of the battery module 100. In addition, the overall control unit 60 is located inside the case 30. Therefore, the case 30 may further provide reliable accommodation and protection for the control unit 60, and implement cooling for the control unit 60 by using a heat dissipation structure in the case 30.
In the embodiment of
Specifically, with reference to
With reference to
On a side of the second control panel 61b, a conducting wire 71 is further disposed in the battery module 100. After the second hollow hole 374b exposes the conducting interface 611b, the conducting interface 611b may be electrically connected to the conducting wire 71, and is connected to an external circuit through the conducting wire 71. Therefore, when the optimizer works, the battery module 100 can be switched to a short-circuit state through electrical connection to the external circuit.
It may be understood that, in the foregoing embodiment, a shape and a location of an external interface of the control panel 61 are determined based on different functions of the control panel 61. Therefore, when a function of the control panel 61 changes with a requirement, or an arrangement location of an external interface in the control panel 61 needs to be adjusted, a corresponding external interface of the control panel 61 (for example, the interface structure 611a and the conducting interface 611b) further needs to be adjusted correspondingly in a matching manner. A specific location of the external interface does not affect implementation of a specific function of the battery module 100 in this application.
In addition, the body structure of the air exhaust panel 37 covers a side that is of the first cover 62a and that is away from the first control panel 61a and a side that is of the second cover 62b and that is away from the second control panel 61b, and provides accommodation and protection for both the first control panel 61a and the second control panel 61b. Therefore, the body of the air exhaust panel 37 may be alternatively used as a part of the cavity 62, and is configured to guide air at the first control panel 61a and the second control panel 61b to flow towards the air supply unit 50. To be specific, the first cover 62a and the body of the air exhaust panel 37 may jointly form the cavity 62 corresponding to the first control panel 61a. The second cover 62b and the body of the air exhaust panel 37 jointly form the cavity 62 corresponding to the second control panel 61b.
In some embodiments, with reference back to
With reference to a schematic diagram of
Similarly, on one side of the air intake board 31, the main ventilation hole 381 may be disposed at a location corresponding to the middle separators 20. Specifically, the main ventilation hole 381 corresponding to the main air intake end 231 of the main air duct 23 is disposed. It can be learned from
Further, with reference to a schematic diagram in
In other words, the ventilation holes formed by both the main ventilation holes 381 and the side ventilation holes 382 may be disposed at locations corresponding to the middle separators 20. In this embodiment of this application, that the ventilation holes correspond to the middle separators 20 in location may be understood as that location dimensions of the ventilation holes along the third direction 003 correspond to the locations of the middle separators 20. In addition, for the air intake board 31, the location dimensions of the main ventilation holes 381 may be alternatively disposed corresponding to the middle separators 20 along the second direction 002. For the first side board 33 and the second side board 32, the location dimensions of the side ventilation holes 382 are disposed corresponding to the middle separators 20 along the first direction 001. Further, for an embodiment in which a first section 2011 and a second section 2021 are further respectively disposed on the first side board 31 and the second side board 32, the side ventilation holes 382 may be alternatively disposed at locations corresponding to the first section 2011 and the second section 2021. The first secondary air duct 21 or the second secondary air duct 22 is not disposed in a location outside the first section 2011 and the second section 2021 of the middle separator 20. Therefore, by disposing the side ventilation holes 382 corresponding to the first section 2011 and the second section 2021, air intake requirements of the first secondary air duct 21 and the second secondary air duct 22 may be met.
Refer back to the schematic diagram in
Refer to a schematic diagram shown in
A length direction of each top support strip 353 further extends along the second direction 002. A plurality of top air holes 354 are further disposed on each top support strip 353. In the schematic diagram shown in the figure, the plurality of top air holes 354 are also spaced along the second direction 002. In this way, a top air flow channel that penetrates the top assembly 35 is formed along the first direction 001. In an embodiment in which through-hole structures are disposed on the top panel 351, external air may enter the top air flow channel from the through-hole structures, and successively pass through each top air hole 354 on the top support board 352 to reach the air exhaust board 32.
It can be learned from
Correspondingly, a bottom panel 361 and a bottom support board 362 are further disposed on the bottom assembly 36. The bottom panel 361 and the bottom support board 362 are spaced and fastened. A plurality of spaced bottom support strips (not shown in the figure) may be further disposed on the bottom panel 361 and/or the bottom support board 362 in a fastened manner. Bottom ventilation holes (not shown in the figure) are further disposed on each bottom support strip, to form a bottom air flow channel inside the bottom assembly 36. The bottom air flow channel also extends along the first direction 011, and is configured to implement a heat dissipation function for the electrochemical cell assembly 10. It may be understood that the secondary ventilation holes 383 of the air intake board 31 may be alternatively disposed corresponding to the bottom air flow channel. Similarly, the secondary air exhaust holes 322 of the air exhaust board 32 may be disposed corresponding to the bottom air flow channel. The cooling air may enter the bottom air flow channel from the secondary ventilation holes 383, and be exhausted out of the case 30 from the secondary air exhaust holes 322, to implement heat dissipation for the electrochemical cell assembly 10. In some embodiments, a plurality of through-hole structures may be alternatively disposed on the bottom panel 361, to assist in air intake of the bottom air flow channel. In the battery module 100 in this application, the middle separator 20 is configured to implement a function of heat dissipation for two opposite sides of two stacked electrochemical cell layers. However, in a stacking direction of each electrochemical cell layer, heat dissipation for two opposite planes of the electrochemical cell assembly 10 is implemented respectively through the top air flow channel and the bottom air flow channel. By disposing of the top air flow channel and the bottom air flow channel, a heat dissipation area of the electrochemical cell assembly 10 is increased, and the heat dissipation effect for the battery module 100 in this application may be further improved.
Alternatively, in one embodiment, the top support board 352 and the bottom support board 362 may be separately attached to the electrochemical cell assembly 10, to implement direct conduction of heat of the electrochemical cell assembly 10. However, in a schematic diagram of
Refer to a plan view shown in
The middle separator 20 needs to dissipate heat for two stacked electrochemical cell layers (for example, the first electrochemical cell layer 11 and the second electrochemical cell layer 12) at the same time, while the top air flow channel and the bottom air flow channel dissipate heat for only one electrochemical cell layer separately. For example, in this embodiment, the top air flow channel dissipates heat for the first electrochemical cell layer 11, and the bottom air flow channel dissipates heat for the fourth electrochemical cell layer 14. Therefore, when the sum of the areas of the secondary ventilation holes 383 is the same as the sum of the areas of the main ventilation holes 381, or the sum of the areas of the secondary ventilation holes 383 is greater than the sum of the areas of the main ventilation holes 381, the following circumstance is caused: Heat dissipation effects of two electrochemical cell layers close to the top assembly 35 and the bottom assembly 36 in the electrochemical cell assembly 10 are better, and heat dissipation effects of electrochemical cell layers in the middle of the electrochemical cell assembly 10 (the second electrochemical cell layer 12 and the third electrochemical cell layer 13 in this embodiment) are relatively poor. Therefore, it does not help to control the temperature difference between the electrochemical cell layers in the electrochemical cell assembly 10.
Through the foregoing disposition, namely, the sum of the areas of the secondary ventilation holes 383 is controlled to be less than the sum of the areas of the main ventilation holes 381, it may be ensured that the flow of the cooling air in the middle separator 20 is greater than the flow of the cooling air in the top air flow channel and the bottom air flow channel, thereby reducing the temperature difference between the electrochemical cell layers in the electrochemical cell assembly 10 and prolonging a service life of the battery module 100 in this application. Similarly, a sum of areas of the main air exhaust holes 321 in the air exhaust board 32 may be alternatively set to be greater than a sum of areas of the secondary air exhaust holes 322, and effect of controlling the flow of the cooling air in the middle separator 20 to be greater than the flow of the cooling air in the top air flow channel and the bottom air flow channel may also be achieved.
In an embodiment, a ratio of the sum of the areas of the single row of secondary ventilation holes 383 to the sum of the areas of the single row of main ventilation holes 381 is set to range from 40% to 80%, and is preferably 60%; and/or a ratio of the sum of the areas of the single row of secondary air exhaust holes 322 to the sum of the areas of the single row of main air exhaust holes 321 is set to range from 40% to 80%, and is preferably 60%. The temperature difference between the electrochemical cell layers in the battery module 100 may be smaller.
Refer to a schematic exploded view shown in
Refer to schematic diagrams shown in
In an embodiment, in a schematic diagram of
Therefore, refer to a schematic diagram shown in
Similarly, the first insulation cover 41 further includes a first outer surface (not shown in the figure) away from the electrochemical cell assembly 10. A plurality of first air guide grooves (not shown in the figure) may be alternatively disposed on the first outer surface. The plurality of first air guide grooves are respectively communicated with the first through holes 412. In addition, the plurality of first air guide grooves further separately extend along the first direction 001. Alternatively, for the cooling air that enters the case 30 from the side ventilation holes 382 on the first side board 33, one part may flow into the first secondary air duct 21 to dissipate heat for the electrochemical cell assembly 10; and the other part may flow along the plurality of first air guide grooves to dissipate heat for the busbars 45 at the first insulation cover 41.
It should be pointed out that a plurality of air guide holes 392 further need to be disposed on the connection board 39. Each air guide hole 392 is communicated to one first air guide groove or second air guide groove 423, so that cooling air in the first air guide groove and the second air guide groove 423 can flow out of the case 30 through the air exhaust window 371. For an embodiment, refer to
For details, refer to
Further, a short busbar 451 and a long busbar 452 are further disposed for the busbars 45. The short busbar 451 and the long busbar 452 are respectively located at a head end and a tail end of the series circuit on one side. The short busbar 451 includes a first power connection pin 453. The long busbar 452 includes a second power connection pin 454. The first power connection pin 453 and the second power connection pin 454 are bent respectively corresponding to the short busbar 451 and the long busbar 452, and are located on one side of each electrochemical cell layer along the first direction 001. In other words, in the schematic diagram of
It may be understood that, the short busbar 451 and the long busbar 452 are respectively the head end and the tail end of the series circuit on one side, so that after the first power connection pin 453 and the second power connection pin 454 that are in pairs are connected, the electrochemical cell units 15 in the electrochemical cell assembly 10 are also connected in series. Further, the first power connection pin 453 and the second power connection pin 454 that are close to the air exhaust panel 37 may be further connected to the second control panel 61b shown in
Refer to
Further, the two third support strips 263 are spaced and disposed. A structure of a base board 24 is further disposed between the two third support strips 263, to form an upper main air duct 233 and a lower main air duct 234 in the middle separator 20. In a schematic diagram of
Through structures of the first support strip 261, the second support strip 262, and the third support strips 263, a fitting surface between the middle separator 20 and the electrochemical cell units 15 is raised, and a gap between the main air duct 23 and the electrochemical cell units may allow more cooling air to flow through. In addition, requirements on overall dimensions of the upper main air ducts 233 and the lower main air ducts 234 are further reduced, so that the electrochemical cell units 15 may be more stably attached to the middle separator 20.
In addition, a quantity of main air ducts 23 communicated by each first secondary air duct 21 is the same as a quantity of main air ducts 23 communicated by the second secondary air duct 22 in this embodiment. However, arrangement distances between the plurality of first secondary air ducts 21 are different, and arrangement distances between the plurality of second secondary air ducts 22 are different. In a schematic diagram of
Compared with the structure shown in
For an embodiment, refer to
Refer to
Specifically, refer to
For the upper separator 20a, a general structure of the upper separator 20a is the same as that of the middle separator 20 shown in
For an embodiment, refer to
For an embodiment, refer back to
In an embodiment, a temperature sensor (not shown in the figure) may be further disposed in the battery module 100 in this application. The temperature sensor may be disposed corresponding to the electrochemical cell assembly 10, and is electrically connected to the control panel 61. The temperature sensor is configured to monitor a temperature of the electrochemical cell assembly 10 in real time. After receiving temperature data sensed by the temperature sensor, the control panel 61 may control a rotation speed or power of the fans 51, to adjust a heat dissipation effect in real time. It may be understood that, in some embodiments, there may be alternatively a plurality of temperature sensors. The plurality of temperature sensors are disposed at different locations of the electrochemical cell assembly 10, to respectively monitor real-time temperatures of different parts of the electrochemical cell assembly 10. For example, there may be four temperature sensors. The four temperature sensors are respectively disposed corresponding to the first electrochemical cell layer 11, the second electrochemical cell layer 12, the third electrochemical cell layer 13, and the fourth electrochemical cell layer 14, to respectively monitor temperatures of different electrochemical cell layers.
Heat dissipation measures of the electrochemical cell layers are different, so that temperatures of the different electrochemical cell layers may also be different. In a process of monitoring each electrochemical cell layer, the control panel 61 may correspondingly adjust heat dissipation effect for the different electrochemical cell layers by controlling rotation speeds or power of the different fans 51, to achieve effect of balancing the temperatures between the different electrochemical cell layers and reducing an internal temperature difference of the electrochemical cell assembly 10. It may be understood that, a difference of working efficiency is formed under control of the control panel 61 in implementations of the two fans in this embodiment. The two fans may be considered as the third fan and the fourth fan mentioned above.
Refer to an arrangement manner shown in
However, in a schematic diagram of
As mentioned above, for the electrochemical cell assembly 10 disposed in a stacked manner, heat dissipation effect for an electrochemical cell layer close to a central part of the stacking is poorer than that of an electrochemical cell layer close to two sides of the stacking. Therefore, the first fan 511 with higher air exhaust power is disposed at a location corresponding to the electrochemical cell layer at the central part of the stacking, and the second fans 512 with lower air exhaust power are disposed at locations corresponding to the electrochemical cell layers at the two sides of the stacking. Therefore, a flow rate of cooling air in a middle separator 20 located between the electrochemical cell layers at the central part of the stacking may be higher. Correspondingly, a flow rate of cooling air in a middle separator 20 located between the electrochemical cell layers at the two sides of the stacking, and/or cooling air in the top air flow channel and a bottom air flow channel is lower. In this way, heat dissipation effect can be adjusted for electrochemical cell layers in different parts, and temperature consistency between the electrochemical cell layers in the electrochemical cell assembly 10 can be improved.
The foregoing descriptions are merely specific embodiments of this application, but are not intended to limit the protection scope of this application. Any variation or replacement, for example, reduction or addition of a mechanical part, and a change of a shape of a mechanical part, readily figured out by a person skilled in the art within the technical scope disclosed in this application shall fall within the protection scope of this application. When no conflict occurs, embodiments of this application and the features in the embodiments may be mutually combined. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| PCT/CN2021/074157 | Jan 2021 | WO | international |
This application is a continuation of International Application No. PCT/CN2021/102492, filed on Jun. 25, 2021, which claims priority to International Application No. PCT/CN2021/074157, filed on Jan. 28, 2021. The disclosures of the aforementioned applications are hereby incorporated by reference in their entireties.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CN2021/102492 | Jun 2021 | US |
| Child | 18226995 | US |
