This application claims priority to and the benefit of Korean Patent Application No. 10-2023-0166925 filed at the Korean Intellectual Property Office on Nov. 27, 2023, the entire contents of which are incorporated herein by reference.
The present disclosure relates to a battery pack with enhanced structural rigidity of a frame portion of a battery module.
A secondary battery (or a rechargeable battery) is widely used in a mobile device, an auxiliary electric power device, or the like. In addition, secondary batteries are also attracting attention as a main power source for an electric vehicle, a hybrid electric vehicle, a plug-in hybrid electric vehicle, or the like, which are proposed as alternatives to conventional and diesel vehicles to solve various problems such as air pollution.
In the electric vehicle or the like, a battery module in which a plurality of battery cells are stacked and then electrically connected in series and in parallel is used due to a need for a high-output and large-capacity battery. The battery cells are stacked in the battery module, and terminals exposed at both ends of each battery cell are electrically connected to provide a high voltage.
A frame constituting an outer wall of the battery module uses aluminum and stainless steel (SUS) that can be welded and do not generate rust. A material of a side plate is determined according to a shape and a material of an end plate with a surface where a swelling force and a compression force required for assembly act in one direction according to a direction in which the battery cell is disposed. If the end plate and the side plate are made of different materials, a same material may be included inside the plate in a special case because welding does not reach a required strength.
In a long battery module having a predetermined length or more, the battery module may have a flange shape protruding from a side surface thereof so as to be fixed to a frame portion of a battery pack at a plurality of positions. In the long battery module, the flange requires sufficient thickness and rigidity to fix the module with a relatively heavy volume.
Embodiments of the present disclosure provide a battery pack in which structural rigidity of a frame supporting battery cells of a battery module is strengthened and a space efficiency of a battery is improved by reducing a thickness when a battery module using roll forming is manufactured.
A battery pack according to embodiments of the present disclosure includes: a frame portion forming an accommodation space; a plurality of battery modules positioned in the accommodation space of the frame portion; a lower cover that covers a lower portion of the frame portion; and an upper cover that covers an upper portion of the frame portion. Each of the battery modules includes: a plurality of battery cells; a plurality of side plates including bent portions that are coupled to the frame portion and support side surfaces of the plurality of battery cells; and a plurality of end plates that connect ends of the side plates to each other.
Each of the side plates includes an inner surface that supports the side surfaces of the battery cells, and each of the side plates is bent along an upper edge to form a folded portion that is in contact with a surface of the side plate.
The folded portion may be welded to the surface of the side plate.
An end portion of the folded portion may include a bent portion protruding from the side plate.
Each of the bent portions may include a plurality of screw holes and a plurality of cutout portions are formed between the plurality of screw holes, and fastening members may be inserted into the screw holes to fix the bent portion to the frame portions.
The cutout portions may be formed in trapezoidal shapes.
Each of the side plates may include bent support portion formed at a lower portion of the side plate that support a lower surface of the battery module.
Each of the side plates may be roll formed.
An insulating film may be attached to a surface of the side plate facing the battery cells.
Each of the side plates may include a side surface that supports the side surfaces of the battery cells, and the side surface may include a bent connection portion that is bent and protrudes in a direction away from the side surfaces of the battery cells.
An avoiding bent portion may be formed at an upper edge of each of the side plates, with the avoiding bent portion being bent in the direction away from the side surfaces of the battery cells.
A portion of one side surface of each of the side plates may be connected to the side surfaces of the battery cells using an adhesive, and each of the side plates may include an adhesive bent portion that is spaced apart from the side surfaces of the battery cells at a portion of the side plate where the adhesive is applied.
Each of the side plates may include a first side surface that supports the side surfaces of the battery cells and a second side surface that is coupled to a connection flange coupled to the frame portion, and the connection flange may include a connection plate coupled to the second side surface of the side plate and a connection protruding portion protruding in a direction away from the side plate to be coupled to the frame portion.
A portion of each of the side plates to which the connection plates are coupled may be bent so that a bonding bent portion spaced apart from the side surfaces of the battery cells is formed.
An adhesive may be applied between the bonding bent portion and the side surfaces of the battery cells.
The side plate may include: a first side portion that includes a side surface supporting the side surfaces of the battery cells, wherein an upper end of the first side portion includes a first bent outward portion that is bent in a direction away from the battery cells; and a second side portion that is coupled to an upper end of the first side portion, wherein a lower end of the second side portion includes a second bent outward portion that is bent outward in the direction away from the battery cells and is coupled to the first bent portion.
The first side portion and the second side portion may be roll formed.
The battery pack may further include an insulating plate that includes a first end connected to a side surface of one of the end plates, a second end connected to a side surface of another of the end plates, and side surfaces supporting the side surfaces of the battery cells.
The insulating plate may include: a first insulating plate that includes ends connected to side surfaces of the end plates to support the side surfaces of the battery cells; and a second insulating plate that includes a portion welded to a side surface of the first insulating plate and ends connected to the side surfaces of the end plates to support the side surfaces of the battery cells.
The first insulating plate may be bent along a lower edge thereof to form a first bending support portion supporting a lower surface of the battery module, and the second insulating plate may be bent along the lower edge thereof to form a second bending support portion supporting the lower surface of the battery module.
A first upper bent portion may be formed at an upper portion of the first insulating plate and a first lower bent portion may be formed at a lower portion of the first insulating plate, a second upper bent portion may be formed at an upper portion of the second insulating plate and a second lower bent portion may be formed at a lower portion of the second insulating plate, and the first upper bent portion and the second upper bent portion may be welded to each other and the first lower bent portion and the second lower bent portion may be welded to each other.
The first insulating plate and the second insulating plate may be roll formed.
The side plates may be made of stainless steel.
An insulating film may be attached to inner surfaces of the side plates.
According to the embodiments of the present disclosure, a side plate supporting a battery cell may be formed of a SUS material or a steel material and rigidity of a plate portion where a battery module is connected to a frame portion may be improved such that durability thereof is improved.
According to the embodiments of the present disclosure, the side plate supporting the battery module may be manufactured using a roll forming method. Thus, it is possible to prevent increases in costs due to enlargement of a facility required for a battery module and thereby prevent increased facility investment costs.
Embodiments of the present disclosure will be described more fully hereinafter with reference to the accompanying drawings so that those skilled in the art easily implement the embodiments. The present disclosure may be modified in various different ways, all without departing from the spirit or scope of the present disclosure. In order to clearly describe the present disclosure, parts or portions that are irrelevant to the description are omitted in the drawings, and identical or similar constituent elements throughout the specification are denoted by the same reference numerals.
As shown in
The frame portion 100 may include a first side frame 10 and a second side frame 20. A first end frame 30 and a second end frame 40 connect the first side frame 10 and the second side frame 20 to each other. The first side frame 10 may be coupled to one edge of the lower cover 50, and may be installed to support one side of the plurality of battery modules 200. The second side frame 20 may be coupled to the other edge of the lower cover 50 and may be installed to support the other side of the plurality of battery modules 200.
The first end frame 30 may be installed to connect one end of the first side frame 10 and one end of the second side frame 20. For example, one end of the first end frame 30 may be connected to the one end of the first side frame 10 by a fastening member 11, and the other end of the first end frame 30 may be connected to the one end of the second side frame 20 by the fastening member 11.
The second end frame 40 may be installed to connect the other end of the first side frame 10 and the other end of the second side frame 20. For example, one end of the second end frame 40 may be connected to the other end of the first side frame 10 by the fastening member 11, and the other end of the second end frame 40 may be connected to the other end of the second side frame 20 by the fastening member 11.
The accommodation space may be formed inside the frame portion 100 such that the battery module 200 may be installed inside the accommodation space. The lower cover 50 may be coupled to the lower portion of the frame portion 100 and the upper cover 60 may be coupled to the upper portion of the frame portion 100, so that a battery cell 111 accommodated inside the frame portion 100 is supported.
As shown in
The end plate 130 may be installed to connect both ends of each of the first and second side plates 120 to each other. The end plate may include first and second end plates 130. The first and second end plates may be installed with the same size and shape, and hereinafter, the first and second end plates use the same reference numeral 130.
A portion of an edge of the side plate 120 along a length direction may be folded in a direction of one side surface. The side plate 120 may be installed to secure structural rigidity. In some embodiments, a portion of the side plate 120 may be folded to enable an overlapping configuration of the plate so that the structural rigidity is secured. In the present embodiment, the side plate 120 may be formed of a SUS material or a steel material.
Referring to
A bent portion 121a may protrude from an end portion of the folding portion 121 so as to protrude in a side surface direction of the side plate 120. In particular, a portion of the folding portion 121 formed outside the side plate 120 may be bent so that the bent portion 121a may protrude from the side plate.
The side plate 120 at which the folding portion 121 and the bent portion 121 a may be formed by roll forming. In particular, the side plate made of a SUS material or a steel material may be processed by the roll forming. Thus, it is possible to prevent increased costs due to enlargement of a facility required for a part of a long battery module and prevent increased facility investment cost.
One reason why the bent portion 121a protrudes from a side surface of the side plate 120 is to allow the battery module 200 to be coupled to the frame portion 100 by a fastening member so that the battery module 200 is stably fixed to the frame portion 100. To this end, a plurality of bolt holes 121b may be formed in the bent portion 121a for coupling fastening members such as bolt members or the like.
A bending support portion 121c may be formed at a lower portion of the side plate 120. The bending support portion 121c may be bent at a lower edge of the side plate 120, and may be formed at the lower portion of the side plate 120 to support a lower portion of the battery cell 111.
Thus, the battery cell 111 may be stably fixed in a state in which the battery cell 111 is accommodated inside the frame portion 100.
As shown in
A pair of the side plates 120 may be connected to each other by a pair of the end plates 130. The plurality of battery modules 200 may be inserted into the frame portion 100, and the plurality of battery modules 200 may be disposed in two rows. While the present embodiment describes the plurality of battery modules 200 as being disposed in two rows inserted into the frame portion 100, the present disclosure is not necessarily limited thereto. For example, the battery module 200 may be inserted as a single row in the frame portion 100 in a state in which the insulating plate 140 (described below) is removed.
The insulating plate 140 may be installed at a position between rows of the plurality of battery modules 200. Both ends of the insulating plate 140 may be connected to the pair of end plates 130 at a position between the pair of side plates 120.
As shown in
The insulating plate 140 may include the first insulating plate 141 that has both of its ends connected to side surfaces of the plurality of end plates 130 to support the side surfaces of the plurality of battery cells. The second insulating plate 143 that has a portion welded to a side surface of the first insulating plate 141 and has both ends connected to the side surfaces of the plurality of end plates 130 to support the side surfaces of the plurality of battery cells.
The first insulating plate 141 may be installed to support side surfaces of the plurality of battery cells 111 disposed in a first row among the battery cells 111 that are disposed in two rows. A portion of the first insulating plate 141 along a length direction may be formed to be bent in a state in which both ends of the first insulating plate 141 are connected to the pair of end plates 130. One reason why the portion of the first insulating plate 141 along the length direction is bent is to couple the bent portion to the second insulating plate 143 by contacting the bent portion with the second insulating plate 143. Another reason why the portion of the first insulating plate 141 along the length direction is bent is to apply an adhesive to a space formed between the bent portion of the first insulating plate 141 and side surfaces of the battery cells 111.
In some embodiments, a side surface of the first insulating plate 141 may support the side surfaces of the battery cells 111, a first upper bent portion 141a may be formed at an upper portion of the first insulating plate 141, and a first lower bent portion 141b may be formed at a lower portion of the first insulating plate 141. The first upper bent portion 141a and the first lower bent portion 141b may be bent so that a space is formed between the first upper bent portion 141a and the first lower bent portion 141b and the side surface of the battery cell 111.
The second insulating plate 143 may be installed to support side surfaces of the plurality of battery cells 111 disposed in a second row among the battery cells 111 that are disposed in two rows. A portion of the second insulating plate 143 along a length direction may be formed to be bent in a state in which both ends of the second insulating plate 143 are connected to the pair of end plates 130.
A side surface of the second insulating plate 143 may support the side surfaces of the battery cells 111, a second upper bent portion 143a may be formed at an upper portion of the second insulating plate 143, and a second lower bent portion 143b may be formed at a lower portion of the second insulating plate 143.
In a state in which the first insulating plate 141 and the second insulating plate 143 are disposed adjacent to each other, the first and second upper bent portions 141a and 143a may be in surface contact with each other, and the first and second lower bent portions 141b and 143b may be in surface contact with each other. Portions of the first and second upper bent portions 141a and 143a and portions of the first and second lower bent portions 141b and 143b that are in surface contact with each other may be welded and coupled to each other.
Each of the first and second upper bent portions 141a and 143a and the first and second lower bent portions 141b and 143b may be formed so as to be retracted from positions of side surfaces of the first and second insulating plates 141 and 143 that are in contact with the battery cells 111. Thus, welding heat may not be transferred to the side surfaces of the first and second insulating plates 141 and 143 during a process in which the first and second upper bent portions 141a and 143a and the first and second lower bent portions 141b and 143b are welded to each other, and the durability of the first and second insulating plates 141 and 143 is thereby improved.
A first bent support portion 141c that supports a lower surface of the battery module may be formed at a lower portion of the first insulating plate 141. In some embodiments, a second bent support portion 143c that supports the lower surface of the battery module may be formed at a lower portion of the second insulating plate 143. The first bent support portion 141c and the second bent support portion 143c may protrude in opposite directions and be formed to support lower portions of the battery cells 111 in different rows.
The insulating film 123 may be attached to the side surfaces of the first and second insulating plates 141 and 143.
As described above, in the battery pack 300 of the present embodiment, the side plate 120 supporting the battery cells 111 may be formed of a SUS material or a steel material and rigidity of a plate portion where the battery module 200 is connected to the frame portion 100 may be further improved, so that durability thereof is improved. Further, because the side plate 120 is manufactured using a roll forming method, a facility required for manufacturing the battery pack may be minimized so that a manufacturing cost is minimized.
As shown in
A plurality of screw holes (not shown) may be formed at the bent connection portion 221. Fastening members such as a bolt members or the like may be inserted to the screw holes to fix the bent connection portion to the frame portion 100 shown in
The bent support portion 121c may be formed at a lower portion of the bent connection portion 221. The bent support portion 121c may be formed at a lower edge of the side plate 220. That is, the bent support portion 121c may be formed at a lower portion of the side plate 220 to support lower portions of the battery cells 111.
The side plate 220 in which the bent connection portion 221 and the bending support portion 121c are formed may be formed by roll forming. A height of the side plate 220 may be determined depending on heights of the battery cells. Further, a height of the bent connection portion 221 may be determined according to a height of a bolt member that is fastened to the frame portion 100. In some embodiments, a protruding length of the bent connection portion 221 may be determined depending on a size of a head portion of the bolt member.
An insulating film (not shown) may be attached to a surface of the side plate 220 contacting the battery cells 111.
As described above, the side plate 220 of the second embodiment of the present disclosure may be more stably fixed to the frame portion 100 by two-layer overlapping protruding shapes of the bent connection portion 221. Thus, durability of the side plate 220 is improved.
As shown in
The avoiding bent portion 321 may be formed by bending a portion of the upper edge of the side plate 320 in an outer direction of the side plate 320. The avoiding bent portion 321 may prevent a damage caused by an insulating film (not shown) attached to an inner surface of the side plate 320 interfering with an upper edge portion of the side plate 320.
As shown in
As shown in
Because the adhesive is applied to the adhesive bent portion 521, the side plate 520 may be stably fixed to the battery cells 111 to stably support the battery cells 111 in an insulating state. The adhesive may be applied to an upper portion, a lower portion, and a middle portion of the side plate 520 and to the adhesive bent portion 521 to thereby provide stable adhesive fixation of the side plate 520 to the battery cells 111. The adhesive may be a structural adhesive, may be a fast-curing polyurethane type adhesive, and may be applied to a surface of the adhesive bent portion 521 at a thickness of 0.2 mm to 1 mm.
The side plate 520 at which the adhesive bent portion 521 is formed may be formed by roll forming.
As shown in
The connection flange 621 may protrude from the side plate 620 and be in surface contact with an outer side surface of the side plate 620. Further, the connection flange 621 may be detachably coupled to the frame portion 100 by a fastening member.
The connection flange 621 may include a connection plate 621a coupled to the outer surface of the side plate 620, and a connection protruding portion 621b protruding to outside of the connection plate 621a to be connected to the frame portion 100. The connection plate 621a may be welded in a state in which the connection plate is in surface contact with the side surface of the side plate 620. That is, the connection plate 621a may be welded to a portion of the side surface of the side plate 620.
With the connection protruding portion 621b protruding from the side surface of the connection plate 621a, and a plurality of screw holes (not shown) may be formed so that the connection protruding portion may be detachably coupled to the frame portion 100 by a bolt member.
The side plate 620 may be formed by roll forming.
As shown in
The side plate 120 at which the bonding bent portion 721 is formed may be formed by roll forming.
As shown in
One side of the bent flange 821 may be coupled to a side surface of the side plate 820, and a portion of the bent flange 821 may protrude from the side surface of the side plate 820 in a state in which the portion of the bent flange is bent at an angle of approximately 90 degrees. The bent flange 821 may be detachably coupled to the frame portion 100 by a bolt member. A bonding bent portion 822 may be formed at a portion where the bent flange 821 is coupled to the side plate 820. Thus, an adhesive may be applied between the battery cell 111 and the bonding bent portion 822, so that the battery cell 111 and the side plate 820 may be bonded to each other.
As shown in
The second side portion 924 may be coupled to an upper portion of the first side portion 922 and a lower end edge of the second side portion 924 may be bent outward. The second side portion 924 may include a second bent portion 924a coupled to the first bent portion 922a.
The first bent portion 922a and the second bent portion 924a may be formed to have the same length and may be welded and coupled. The first and second bent portions 922a and 924a may protrude from one side of the side plate 920 to be coupled to the frame portion 100. To this end, the first bent portion 922a and the second bent portion 924a may include a plurality of screw holes (not shown) formed in a state in which the first bent portion 922a and the second bent portion 924a are welded. The first and second bent portions 922a and 924a may therefore be be detachably coupled to the frame portion 100 by fastening members inserted into the screw holes.
The first side portion 922 and the second side portion 924 may be formed by roll forming.
As shown in
The cutout portions 1222 may be cut in trapezoidal shapes between the plurality of screw holes 121b. But the cutout portions 1222 are not necessarily limited to a trapezoidal shape, and the cutout portions 122 may be changed to various polygonal shapes.
A cut width of the cutout portions 1222 may be larger than a width of the bending portion 1221 in which the screw hole 121b is formed. Thus, if a pair of battery modules 1300 are disposed inside the frame portion 100 as shown in
While this disclosure has been described in connection with what is presently considered to be practical embodiments, it is to be understood that the disclosure is not limited to the disclosed embodiments. On the contrary, the disclosure is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2023-0166925 | Nov 2023 | KR | national |