Patent Application
20230040054
This application claims priority to and the benefit of Korean Patent Application No. 10-2020-0052258 filed in the Korean Intellectual Property Office on Apr. 29, 2020, the entire contents of which are incorporated herein by reference.
The present invention relates to a battery pack and a device including the same, and in particular, it relates to a safety-improved battery pack and a device including the same.
Rechargeable batteries having high application characteristics and electrical characteristics such as high energy density according to their products are widely applied to battery vehicles, hybrid vehicles, and electric power storage devices driven by electric driving sources, as well as portable devices. These rechargeable batteries are attracting attention as new energy sources for improving environmental friendliness and energy efficiency in that they do not generate any by-products of energy use, as well as their primary merit that they can drastically reduce the use of fossil fuels.
The commercially available secondary batteries include a nickel cadmium battery, a nickel hydrogen battery, a nickel zinc battery, and a lithium secondary battery, and the lithium secondary battery among them scarcely generates a memory effect compared to the nickel-based secondary battery so it is freely charged and discharged, a self-discharge rate is very low, and an energy density is high as merits.
The lithium secondary battery generally uses a lithium-based oxide and a carbon material as a positive active material and a negative active material, respectively. The lithium secondary battery includes an electrode assembly in which a positive electrode plate and a negative electrode plate on which the positive active material and the negative active material are respectively applied are disposed with a separator therebetween, and an exterior material, that is, a battery case, for sealing and receiving the electrode assembly together with an electrolyte solution.
In general, the lithium secondary battery may be classified into a cylindrical or square-type secondary battery of which the electrode assembly is installed in a metal can, and a pouch-type secondary battery of which the electrode assembly is installed in a pouch of an aluminum laminate sheet, depending on a shape of the exterior material.
Recently, as needs for a large-capacity secondary battery structure increase in addition to the use as an energy storing source of the secondary battery, needs for the battery packs in a medium to large module structure in which battery modules in which a plurality of secondary batteries are coupled in series or in parallel are gathered are increasing. Capacity and outputs of the battery modules are improved by coupling a plurality of battery cells in series or in parallel and configuring a battery cell stacked body. Further, a plurality of battery modules may configure a battery pack when installed together with various control and protection systems such as a battery management system (BMS) or a cooling system.
The battery pack has a structure in which a plurality of battery modules are combined, so when some of the battery modules receive an overvoltage or an overcurrent or they are overheated, safety and operation efficiency of the battery pack may be problematic. Particularly, while the capacity of the battery pack is in the increasing trend to improve mileage and energy inside the pack is accordingly increasing, there is a need to design a structure satisfying reinforcing safety standards and obtaining safety of vehicles and drivers. For this purpose, the need for acquiring a structure for preventing an internal thermal runaway in advance, and minimizing corresponding damages when the thermal runaway is generated, is particularly on the rise.
The present invention has been made in an effort to provide a safety-improved battery pack and a device including the same.
However, the objective of the present invention is not limited to the aforementioned one, and may be extended in various ways within the spirit and scope of the present invention.
An embodiment of the present invention provides a battery pack including: a plurality of battery modules; a venting inducing frame disposed along an edge of the battery modules and forming a venting passage; a venting gate for connecting an inside of the battery modules and the venting inducing frame; a rupture portion formed on an outside of the venting inducing frame; and a unidirectional valve formed on a passage of the venting inducing frame, wherein the unidirectional valve intercepts a passage in a direction connected to a venting gate connected to a second battery module from the venting gate connected to one battery module from among the battery modules, and opens a passage in a direction connected to the rupture portion from the venting gate connected to one battery module from among the battery modules.
The unidirectional valve may be opened or closed according to a direction in which a pressure is applied.
The venting inducing frame may include a pair of vertical beams formed in parallel to a first direction and a pair of horizontal beams formed in parallel to a second direction traversing the first direction, the vertical beams and the horizontal beams respectively may include a cover formed in a length direction of the vertical beams and the horizontal beams, and a passage surrounded by the cover and formed to allow gas to pass through, and the at least one unidirectional valve may be formed on the passage.
A 1-1 passage and a 1-2 passage may be formed on the pair of vertical beams, respectively, a 2-1a passage and a 2-1b passage may be separately formed in one of the pair of horizontal beams, and a 2-2a passage and a 2-2b passage may be separately formed in the other of the pair of horizontal beams.
The unidirectional valve may be respectively formed on one of the 1-1 passage, the 2-1 a passage, and the 2-2a passage connected to each other, and on one of the 1-2 passage, the 2-1b passage, and the 2-2b passage connected to each other.
A notch may be formed in a middle of the pair of horizontal beams, and the 2-1a passage and the 2-1b passage, and the 2-2a passage and the 2-2b passage, may be formed on respective sides of the notch.
The venting gate may be connected to one of the passages formed on respective sides of the notch.
A rupture portion may be formed on respective sides of one of the pair of horizontal beams, and the rupture portion may be respectively connected to the 2-1a passage and the 2-1b passage.
The battery pack may further include a housing for receiving the battery modules and the venting inducing frame, wherein the housing may include an upper cover and a lower housing, and a pack gasket may be formed between the upper cover and the lower housing.
Another embodiment of the present invention provides a device including the above-described battery pack. According to the embodiments, the venting inducing structure is provided in the battery pack, so when an abnormal phenomenon is generated in the battery cell, the safety of the battery pack may be secured by inducing venting gas in a predetermined direction.
The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present disclosure.
Parts that are irrelevant to the description will be omitted to clearly describe the present invention, and the same elements will be designated by the same reference numerals throughout the specification.
The size and thickness of each configuration shown in the drawings are arbitrarily shown for better understanding and ease of description, but the present invention is not limited thereto. In the drawings, the thickness of layers, films, panels, regions, etc., are exaggerated for clarity. For ease of description, the thicknesses of some layers and areas are exaggerated.
It will be understood that when an element such as a layer, film, region, or substrate is referred to as being “on” another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present. Further, in the specification, the word “on” or “above” means disposed on or below the object portion, and does not necessarily mean disposed on the upper side of the object portion based on a gravitational direction.
Unless explicitly described to the contrary, the word “comprise” and variations such as “comprises” or “comprising” will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.
Further, throughout the specification, the phrase “in a plan view” means viewing a target portion from the top, and the phrase “in a cross-sectional view” means viewing a cross-section formed by vertically cutting a target portion from the side.
Referring to
In this instance, the battery cell stacked body 102 according to an embodiment of the present invention may be a large-area module including a greater number of the battery cells 101 than the prior art. For example, 48 battery cells 101 may be included per battery module 100. Regarding the large-area module, a horizontal direction length of the battery module becomes long. In this instance, the horizontal direction length may signify a direction in which the battery cells 101 are stacked, that is, the length in the direction that is parallel to the y-axis.
The module frame 108 for receiving the battery cell stacked body 102 may include an upper plate 112 and a lower frame 111. The lower frame 111 may be a U-shaped frame. The U-shaped frame may include a bottom portion and two lateral portions extending upward from respective ends of the bottom portion. The bottom portion may cover a lower side (an opposite direction of a z axis) of the battery cell stacked body 102, and the lateral portions may cover respective lateral sides (the y-axis direction and its opposite direction) of the battery cell stacked body 102.
The upper plate 112 may be formed to have one plate-shaped structure for surrounding a remaining upper side (z-axis direction) excluding the lower side and the respective sides surrounded by the U-shaped frame. The upper plate 112 and the lower frame 111 may be combined to each other by welding while corresponding corners contact each other, thereby configuring a structure for covering the battery cell stacked body 102 from top to bottom and from right to left. The battery cell stacked body 102 may be physically protected through the upper plate 112 and the lower frame 111. For this purpose, the upper plate 112 and the lower frame 111 may include a metallic material with predetermined rigidity.
A venting gate 121 for communicating with an inside of the battery module 100 and releasing a flame or heat that may be generated in the inside is disposed on the end plate 120 according to the present embodiment. The venting gate 121 may be provided on a lower side of the end plate 120 by considering a connector connecting portion for transmitting information. The venting gate 121 may be connected to an opening (not shown) formed in part of the end plate 120, and it may communicate with an inside of the battery module 100.
The module frame 108 may include a module frame protrusion 131 formed so that the bottom portion of the module frame 108 may extend to pass through the end plate 120. In this instance, a coolant input and output by a cooling port 140 connected to an upper side of the module frame protrusion 131 may be supplied to/discharged from a heat sink 130 through the module frame protrusion 131.
Referring to
The pack housing 400 may include a lower housing 410 for receiving the pack tray 200, and an upper cover 420 combined to the lower housing 410 and covering an upper side of the battery module 100. A pack gasket 411 may be formed between the upper cover 420 and the lower housing 410 to close and seal the inside of the pack housing 400.
The battery modules 100 respectively include a battery cell stacked body disposed in the module frame 110, and include an end plate 120 for covering the battery cell stacked body exposed to the respective ends of the module frame 110. In this instance, one of the respective end plates 120 includes a venting gate 121 communicating with the inside of the battery module 100 and releasing the flame or heat that may be generated from the inside. In the battery pack 1000, the venting gate 121 is disposed to face an external side of the battery pack 1000, and preferably, as shown in
A venting inducing frame 300 may be disposed along the edge of all the battery modules 100. The venting inducing frame 300 may include a pair of vertical beams 310 and a pair of horizontal beams 320 formed in a pipe shape along the respective sides of the battery pack 1000 and respectively extending in the first direction (x-axis direction) and the second direction (y-axis direction), and they are formed to communicate with each other as a whole body. A detailed configuration of the venting inducing frame 300 will be described in a later portion of the present specification.
The battery modules 100 and the venting inducing frame 300 may be mounted on the pack tray 200, and may be fixed to the pack tray 200 by a fixation means as needed. The battery module 100, the venting inducing frame 300, and the pack tray 200 may be received in the lower housing 410. The lower housing 410 may include a bottom side on which the pack tray 200 is disposed, and a side wall extending upward from the edge of the bottom side. An upper cover 420 for covering the upper portion of the battery module 100 may be combined to the lower housing 410 to protect an internal electrical field. In this instance, various control and protection systems such as a battery management system (BMS) and a cooling system together with the battery module 100 may be installed in the pack housing 400.
At least one rupture portion 500 for discharging heat or flame generated from the inside to the outside may be formed on one side wall of the lower housing 410. A detailed configuration of the rupture portion 500 will be described in a later portion of the present specification.
A venting inducing frame of a battery pack according to an embodiment of the present invention will now be described in detail.
Referring to
The vertical beams 310 have a pipe shape lengthily extending in the first direction (x-axis direction), and include a cover 311 for defining an inside of the pipe shape, and a passage 312 formed inside the cover 311. The cover 311 may include a first internal cover 311a disposed near the battery module 100 in the second direction (y-axis direction), and a first external cover 311b facing the same and disposed to become distant from the battery module 100 in the second direction (y-axis direction). At least one of the first internal cover 311a and the first external cover 311b includes a groove lengthily formed in the first direction. That is, its cross-section is formed to have a “⊏” shape (formed to have a shape in which one side is removed from a square pipe shape), and the cover of the other is combined thereto to thus define the passage 312. However, it is not limited thereto as long as the pipe shape may be obtained by the cover 311.
The horizontal beams 320 have a pipe shape lengthily extending in the second direction (y-axis direction), and includes a cover 321 for defining an inside of the pipe shape, and a passage 322 formed inside the cover 321. The cover 321 may include a second internal cover 321a disposed near the battery module 100 in the first direction (x-axis direction), and a second external cover 321b facing the same and disposed to become distant from the battery module 100 in the first direction (x-axis direction). At least one of the second internal cover 321a and the second external cover 321b includes a groove lengthily formed in the second direction That is, its cross-section is formed to have a “⊏” shape (formed to have a shape in which one side is removed from a square pipe shape), and the cover of the other is combined thereto to thus define the passage 322. Particularly, in the present embodiment, as shown in
The horizontal beams 320 includes a first connection hole 324 formed on the side facing the battery module 100, that is, one side of the second internal cover 321a. The first connection hole 324 is disposed to communicate with the venting gate 121 of the battery module 100. The horizontal beams 320 further includes a third connection hole 326 formed on the side disposed in a direction becoming distant in the second direction from the battery module 100, that is, one side of the second external cover 321b. The third connection hole 326 is disposed so that the rupture portion 500 may communicate with the passage 322. In this instance, the venting path bracket 328 may combine the rupture portion 500 and the horizontal beams 320 to guide the path for the venting gate 121, the passage 322 of the horizontal beams 320, and the rupture portion 500 to communicate with each other.
The vertical beams 310 include a second connection hole 314 formed on the first internal cover 311a at the respective ends disposed near the horizontal beams 320. The passage 322 of the horizontal beams 320 may communicate with the passage 312 of the vertical beams 310 through the second connection hole 314.
The rupture portion 500 is connected to the passage 322 of the horizontal beams 320 and includes a rupture side (510, shown in
In the present embodiment, the rupture portion 500 is connected to the passage 322 of the horizontal beams 320, and the rupture portion 500 is fixed with the horizontal beams 320 and the lower housing 410, and without being limited thereto, configurations for communicating with the passage of the venting inducing frame 300 and discharging to the outside may be appropriately used. Further, the formation of two rupture portions 500 on one of the pair of horizontal beams 320 is exemplified in the present embodiment, and without being limited thereto, the rupture portion 500 may be installed in the horizontal beams 320 on another side, or it may be installed in the vertical beams 310, and corresponding positions and numbers may be appropriately selected as needed.
By the above-noted configuration, the passage is formed to communicate with all components inside the venting inducing frame 300 in a square shape configured with the vertical beams 310 and the horizontal beams 320, and the passage communicates with the venting gate 121 of the battery module 100 and the rupture portion 500 to induce heat and flame to the outside and minimize the influence to peripheral battery modules when a thermal runaway is generated from the battery module 100. In this instance, the flame included in the generated high-pressure venting gas is combusted while passing through the path inside the venting inducing frame 300 and it may be discharged to the outside in a safer way. In the normal condition without a thermal runaway, the venting inducing frame 300 may function as a support frame for stably supporting the battery module 100 and may improve stability of the battery pack 1000.
A path for controlling a case in which issues such as overvoltage, overcurrent, or overheating are generated in some battery modules in the battery pack will now be described.
Referring to
For example, when heat is generated in the battery module 100 disposed on the position 1 in
Further, when heat is generated in the battery module 100 disposed on the position 2 in
Referring to
A battery pack in which a unidirectional valve is formed according to an embodiment of the present invention will now be described.
The unidirectional valve 600 may be opened or closed according to the direction in which a pressure is applied. As shown in
According to the present specification, the unidirectional valve 600 is formed on the passage of the venting inducing frame 300. Referring to
According to what is shown with reference to
As shown in
In detail, as shown in
As shown in
Referring to
As shown in
The rupture portion 500 may be formed on respective sides of one of the pair of horizontal beams 320. In detail, the rupture portion 500 may be respectively connected to the 2-1a passage (P2-1a) and the 2-1b passage (P2-1b).
As shown in
As shown in
The above-described battery module and the battery pack including the same are applicable to various types of devices. The devices include transport means such as electric bicycles, electric vehicles, and hybrid vehicles, but the present invention is not limited thereto, and it may be applied to various devices that use the battery module and the battery pack including the same, which also belongs to the scope of the present invention.
While this invention has been described in connection with what is presently considered to be practical embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2020-0052258 | Apr 2020 | KR | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/KR2021/004397 | 4/8/2021 | WO |
