Cell, battery module, and battery pack

Abstract

To provide a cell and a battery module, in which the generation of gas or the expansion of an electrode sheet is suppressed during a process of charging and discharging the cell.SOLUTION: A cell 10 includes an exterior housing 11, a lid plate 12, and a reinforcement member. The lid plate is welded to an upper part of the exterior housing. The reinforcement member includes at least a first surface and a second surface. The first surface is fixedly connected to one of the lid plate and the exterior housing. The second surface faces the other of the lid plate and the exterior housing.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to the technical field of batteries, and in particular to cells, battery modules, and battery packs. [Background technology]

[0002] In conventional prismatic case cells, the assembly of the upper cover and the aluminum case is completed by filling the side steps of the aluminum case and the steps around the bottom of the upper cover, and then laser welding is performed to complete the assembly of the case and the cover. The prismatic case cell uses the aluminum case as a current collecting container. When the cell is charged and discharged, gas is generated and the electrode sheet expands, pushing the aluminum case outward and expanding. The gas generated by the cell, the expansion of the electrode sheet, and the resulting outward expansion of the aluminum case cause the welds of the case cover at the corresponding positions to crack. If exposed to fatigue expansion forces for a long period of time, the strength of the welds of the case cover may decrease or the welds may tear and break, affecting the safety of the cell. Summary of the Invention [Problem to be solved by the invention]

[0003] In view of the above-mentioned shortcomings of the related art, the present invention aims to provide a cell and a battery module to solve the problem that during the charging and discharging process of a cell, the aluminum housing will expand outward due to gas generation or expansion of the electrode sheet, causing the welds of the housing cover at the corresponding positions to crack, and when exposed to fatigue expansion force for a long period of time, the strength of the welds of the housing cover may decrease or the welds may break and be damaged, affecting the safety of the cell. During the charging and discharging process of the existing battery cells, gas will be generated, causing the pole pieces to expand, and the aluminum shell to expand outward, causing the welds of the shell cover to tear at the corresponding positions and be affected by fatigue expansion forces. After long-term use, the weld strength of the shell cover may be weakened or even torn and broken, affecting the safety of the battery core. [Means for solving the problem]

[0004] To achieve the above and other related objectives, the present invention provides a cell including an exterior housing, a cover plate, and a stiffening member.

[0005] The cover plate is welded to the top of the exterior housing.

[0006] The reinforcing member includes at least a first surface and a second surface, the first surface being fixedly connected to one of the cover plate and the exterior housing, and the second surface facing the other of the cover plate and the exterior housing.

[0007] In one embodiment of the present invention, the cell further comprises an electrode assembly stacked within the exterior housing in the thickness, length or height direction of the cell, When the electrode assembly is stacked in the thickness direction, a first surface is fixedly connected to the cover plate and a second surface faces a larger surface of the exterior housing.

[0008] When the electrode assemblies are stacked lengthwise, the first surface is fixedly connected to the cover plate and the second surface faces a narrow surface of the outer housing.

[0009] When the electrode assemblies are stacked in the height direction, the first surface is fixedly connected to the exterior housing and the second surface faces the cover plate.

[0010] In one embodiment of the invention, the reinforcing member is an L-shaped reinforcing member, a C-shaped reinforcing member, a T-shaped reinforcing member, or a ring-shaped reinforcing member.

[0011] In one embodiment of the present invention, the ratio of the length of each of the L-shaped reinforcing member, the C-shaped reinforcing member, and the T-shaped reinforcing member to the length of the cover plate is 1 or less.

[0012] In one embodiment of the present invention, the width of the L-shaped reinforcing member on the cover plate close to the explosion-proof valve is less than or equal to (ab) / 2, where a is the width of the cover plate and b is the width of the explosion-proof valve.

[0013] In one embodiment of the invention, each of the L-shaped, C-shaped, and T-shaped reinforcement members includes a plurality of segmented reinforcement members, and the plurality of segmented reinforcement members are spaced apart.

[0014] In one embodiment of the present invention, the C-shaped reinforcing member further includes a third surface, the third surface and the second surface facing two opposite broad surfaces of the exterior housing respectively, and an escape groove is provided on the first surface, the escape groove facing the explosion-proof valve of the cover plate.

[0015] In one embodiment of the present invention, the cell further includes an upper patch, a groove is provided on a side of the upper patch closer to the reinforcing member to form an avoidance area, and a portion of the reinforcing member provided on the cover plate is located in the avoidance area.

[0016] In one embodiment of the present invention, a heat-shrinkable sleeve film, an insulating tape, P The insulating layer further includes a heat shrinkable sleeve film that surrounds the top of the cell and covers the surface of the reinforcing member. The surface of the reinforcing member is covered with an insulating tape. P Can be pasted.

[0017] In one embodiment of the present invention, an insulating tape P's The ends protrude from both ends of the reinforcing member, and the portions protruding from the reinforcing member are folded to cover the sides of the reinforcing member.

[0018] The present invention further provides a battery module including a housing body, a cell stack, and a reinforcing member.

[0019] The cell stack includes a plurality of cells, each of which includes an exterior housing and a cover plate welded to the top of the exterior housing.

[0020] The reinforcing member is the outermost part of the cell stack. Located in Located at least on the exterior of the two cells, each reinforcing member includes at least a first surface and a second surface, where the first surface is fixedly connected to one of the cover plate and the exterior housing, and the second surface faces the other of the cover plate and the exterior housing.

[0021] In one embodiment of the invention, each cell is provided with a reinforcing member.

[0022] In one embodiment of the present invention, the cell stack includes an even number of single cell groups, each single cell group including at least one cell, and the single cell groups are connected in series.

[0023] In one embodiment of the present invention, the cell stack includes a plurality of single cells, and the reinforcing members are installed on two cells located on either side of the single cell group.

[0024] In one embodiment of the present invention, a T-shaped reinforcing member is installed on the adjacent sides of two adjacent single cell groups. The T-shaped reinforcing member includes a wing plate, a sub-plate, two first surfaces, and two second surfaces. The two second surfaces are respectively installed on both sides of the sub-plate, and the two first surfaces are respectively installed on the bottom of the wing plate on both sides of the sub-plate.

[0025] The present invention further provides a battery pack including the above-mentioned cell or the above-mentioned battery module. Effect of the Invention

[0026] The present invention provides a cell, a battery module, and a battery pack. The problem of cycle cracking caused by insufficient strength of the welded portion is solved by installing a reinforcing member in the cell. Furthermore, the relative displacement between the cell's housing body and the upper cover is limited, so that the welded portion is not damaged during cycling, the housing cover's welded portion is effectively protected, and the expanded cell is protected. Furthermore, the reinforcing member is connected to the cover plate and the housing body by laser welding or adhesive, so that no separate device is required and the work is easy and efficient.

[0027] The present invention provides a cell, a battery module and a battery pack, in which the upper cover patch is provided with a workaround design, and the reinforcing member is coated and covered to solve the problem of aluminum exposure at one end of the upper cover caused by welding the reinforcing member, thereby achieving a good external insulation effect and ensuring the external insulation performance of the cell.

[0028] The present invention provides a cell, a battery module, and a battery pack. Located in By installing reinforcing members on at least the outside of the two cells, the safety of the battery module is improved by preventing the relative displacement between the housing body of the outermost cell and the top cover from causing the welds to burst during the expansion cycle of the cells.

[0029] The present invention provides a cell, a battery module, and a battery pack. When a cell stack includes an even number of cells, and the positive and negative electrodes of each cell are alternately arranged, the L-shaped reinforcing member is disposed on the outermost side of the cell stack. Located in Only the outer two cells are installed. In this way, the welds are prevented from breaking during the cell expansion cycle. Furthermore, if the number of cells is even, the outermost Located in Since the two cells are completely identical, only one production line is needed to manufacture the cell with the reinforcing member, which can effectively reduce the production cost. [Brief description of the drawings]

[0030] In order to more clearly show the technical solutions provided in the embodiments of the present invention, some accompanying drawings necessary for the embodiments are briefly introduced below for explanation. Obviously, the drawings in the following description are only some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative efforts. [Figure 1] FIG. 2 is a schematic diagram of a cell equipped with an L-shaped reinforcing member according to one embodiment of the present invention. [Diagram 2] 1 is a schematic configuration diagram of an L-shaped reinforcing member according to an embodiment of the present invention. [Diagram 3] FIG. 4 is a schematic cross-sectional view showing welding of an L-shaped reinforcing member according to one embodiment of the present invention. [Figure 4] 4 is a schematic cross-sectional view showing the adhesion of an L-shaped reinforcing member according to one embodiment of the present invention. FIG. [Diagram 5] FIG. 2 is a schematic structural diagram of a cell equipped with a C-shaped reinforcing member according to one embodiment of the present invention. [Figure 6] FIG. 2 is a schematic structural diagram of a C-shaped reinforcing member according to one embodiment of the present invention. [Figure 7] FIG. 2 is a schematic cross-sectional structural view of a cell equipped with a C-shaped reinforcing member according to one embodiment of the present invention. [Figure 8] FIG. 2 is a schematic structural diagram of a cell equipped with a T-shaped reinforcing member according to one embodiment of the present invention. [Figure 9] 1 is a schematic structural diagram of a T-shaped reinforcing member according to one embodiment of the present invention. [Figure 10] FIG. 2 is a schematic cross-sectional structural view of a cell equipped with a T-shaped reinforcing member according to one embodiment of the present invention. [Figure 11] FIG. 2 is a schematic structural diagram of a cell with two reinforcing members according to one embodiment of the present invention. [Figure 12] FIG. 2 is a schematic diagram of a segmented C-shaped stiffener according to one embodiment of the present invention. [Figure 13] FIG. 2 is a schematic diagram of a segmented T-shaped reinforcing member according to one embodiment of the present invention. [Figure 14] FIG. 2 is a schematic diagram of a cell including an annular reinforcing member according to one embodiment of the present invention. [Figure 15] 1 is a schematic diagram of an annular reinforcing member according to an embodiment of the present invention; [Figure 16] 1 is a schematic exploded view of a top patch fitted with a reinforcing member according to one embodiment of the present invention; [Figure 17] 1 is a schematic top view of a top patch fitted with a reinforcing member according to one embodiment of the present invention; FIG. [Figure 18] 13 is a schematic exploded view of an upper patch fitted with a reinforcing member according to another embodiment of the present invention. FIG. [Figure 19]13 is a schematic cross-sectional view of a top patch fitted with a reinforcing member according to another embodiment of the present invention. [Figure 20] 2 is a schematic exploded view of a reinforcement member compatible with an insulating tape according to an embodiment of the present invention; FIG. [Figure 21] 2 is a schematic cross-sectional view of a reinforcement member compatible with an insulating tape according to an embodiment of the present invention; [Figure 22] 2 is a schematic top view of a reinforcement member compatible with an insulating tape according to an embodiment of the present invention; FIG. [Figure 23] 23 is a schematic cross-sectional view of a reinforcement member that is compatible with the insulating tape of FIG. 22. [Figure 24] 1 is a schematic structural diagram of a battery module equipped with an L-shaped reinforcing member according to one embodiment of the present invention. [Diagram 25] FIG. 11 is a schematic structural diagram of a battery module including an L-shaped reinforcing member according to another embodiment of the present invention. [Figure 26] 1 is a schematic structural diagram of a battery module equipped with a C-shaped reinforcing member according to one embodiment of the present invention. [Figure 27] FIG. 13 is a schematic structural diagram of a battery module equipped with a C-shaped reinforcing member according to another embodiment of the present invention. [Figure 28] 1 is a schematic structural diagram of a battery module equipped with a T-shaped reinforcing member according to one embodiment of the present invention. [Figure 29] FIG. 13 is a schematic structural diagram of a battery module equipped with a T-shaped reinforcing member according to another embodiment of the present invention. [Diagram 30] 1 is a schematic structural diagram of a battery module including an annular reinforcing member according to an embodiment of the present invention; [Diagram 31] 11 is a schematic structural diagram of a battery module including an annular reinforcing member according to another embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] The implementation of the present invention will be described below through a specific embodiment. Those skilled in the art can easily understand other advantages and effects of the present invention from the disclosure of this specification. The present invention can also be implemented or applied through other different specific implementation methods. The details of this specification can also be modified or changed based on different perspectives and applications without departing from the spirit of the present invention.

[0032] Please note that the drawings provided in the embodiments only show the basic idea of ​​the present invention in a schematic manner. Therefore, the drawings only show components related to the present invention, and are not illustrated according to the number, shape, and dimensions of the components in the actual implementation. In the actual implementation, the type, number, and ratio of the components can be arbitrarily changed, and the type of installation of the components may be more complicated.

[0033] 1 to 23, the present invention provides a cell, a battery module, and a battery pack for solving a problem that affects the safety of a cell, in which the welded portion of the housing cover at a corresponding position may be torn due to the outward expansion of the aluminum housing caused by gas generation or expansion of the electrode sheet during the charging and discharging process of the cell, and the strength of the welded portion of the housing cover may be reduced or the welded portion may be torn and broken when exposed to fatigue expansion force for a long period of time. Specifically, the cell 10 includes an exterior housing 11, a cover plate 12, and a reinforcing member 13, and an opening is provided at the top of the exterior housing 11. The cover plate 12 is provided at the top of the exterior housing 11, specifically, at the opening at the top of the exterior housing 11, and is fixed to the exterior housing 11 by welding. The reinforcing member 13 is provided between the cover plate 12 and the exterior housing 11, and is configured to improve the strength of the welded portion between the cover plate 12 and the exterior housing 11.

[0034] 1 to 23, in this embodiment, the reinforcing member 13 includes at least a first surface 131 and a second surface 132. The first surface 131 is fixedly connected to one of the cover plate 12 and the exterior housing 11, and the second surface 132 faces the other of the cover plate 12 and the exterior housing 11. Preferably, the second surface 132 faces the cover plate 12 or the exterior housing 11 from the front. For example, the first surface 131 is fixedly connected to the cover plate 12, and the second surface 132 faces the surface of the exterior housing 11 from the front. Alternatively, the first surface 131 is fixedly connected to the exterior housing 11, and the second surface 132 faces the cover plate 12 from the front. In this embodiment, the first surface 131 and the cover plate 12 or the exterior housing 11 may be connected by laser welding or an adhesive. The second surface 132 and the exterior housing 11 or the cover plate 12 may be connected by laser welding or adhesive, or may be directly opposite to each other and not fixedly connected to each other. In this way, when the cell 10 expands, the expansion of the cell 10 is restricted, so that the relative displacement between the exterior housing 11 and the cover plate 12 in the cell 10 is restricted, so that the welded part is not damaged during cycling, and the welded part of the housing cover is effectively protected. Note that in this embodiment, the aspect ratio of the cell 10 is greater than 12, and a cell with an aspect ratio less than this ratio is prone to swelling, which may cause the welded part of the housing cover to be damaged. Therefore, by installing the reinforcing member 13 on the cell 10, the expansion of the cell 10 can be restricted when the cell 10 expands.

[0035] 1 to 23, in this embodiment, the cell 10 further includes an electrode assembly stacked in the exterior housing 11. For example, the electrode assemblies may be stacked in the thickness direction X, length direction Y, or height direction Z of the cell. When the electrode assemblies are stacked in the thickness direction, the first surface 131 is fixedly connected to the cover plate 12, and the second surface 132 faces the wide surface 111 of the exterior housing 11. When the electrode assemblies are stacked in the length direction, the first surface 131 is fixedly connected to the cover plate 12, and the second surface 132 faces the narrow surface 112 of the exterior housing 11. When the electrode assemblies are stacked in the height direction, the first surface 131 is fixedly connected to the exterior housing 11, and the second surface 132 faces the cover plate 12. That is, the first surface 131 is configured to fixedly install the reinforcing member 13, and the second surface 132 is configured to limit the relative displacement between the outer housing 11 and the cover plate 12 within the cell 10, so that the welds are not damaged during cycling and the welds of the housing cover are effectively protected.

[0036] 1 to 23, in this embodiment, the reinforcing member 13 may be any one of an L-shaped reinforcing member 133, a C-shaped reinforcing member 134, a T-shaped reinforcing member 135, and a ring-shaped reinforcing member 136. The reinforcing member 13 may be connected to the cover plate 12 and the exterior housing 11 by laser welding or adhesive 1301, so that no additional device is required and the operation is easy and efficient.

[0037] 1 to 4 and 8 to 10, in this embodiment, an example in which the first surface 131 is fixedly connected to the cover plate 12 and the second surface 132 faces the wide surface 111 of the exterior housing 11 is used for explanation. The L-shaped reinforcing member 133 includes one first surface 131 and one second surface 132. The first surface 131 and the second surface are located on one side of the first surface 131 and are bent to the opposite side of the first surface 131. The first surface 131 is welded and fixed to the cover plate 12 by laser welding, and the second surface 132 faces the wide surface 111 of the exterior housing 11. The T-shaped reinforcing member 135 includes a wing plate 1351, a sub-plate 1352, two first surfaces 131, and two second surfaces 132. The two second surfaces 132 are installed on both sides of the subplate 1352, respectively, and the two second surfaces 132 are installed on the bottom of the wing plate 1351 on both sides of the subplate 1352, respectively. Preferably, the subplate 1352 and the wing plate 1352 are installed perpendicular to each other. For example, the T-shaped reinforcing member 135 may be installed between two cells 10. The two first surfaces 131 are welded and fixed to the cover plates 12 of the two cells 10 by laser welding, respectively, and the two second surfaces 132 face the wide surfaces 111 of the exterior housings 11 of the two cells 10, respectively. In this way, one T-shaped reinforcing member 135 can restrict the outward expansion of the wide surfaces 111 of the exterior housings 11 of the two cells 10. In some other embodiments, the first surface 131 and the second surface 132 may be fixedly connected to the cover plate 12 and the broad surface 111 of the outer housing 11 via an adhesive 1301, respectively.

[0038] 1 to 10, in this embodiment, the ratio of the length of each of the L-shaped reinforcing member 133, the C-shaped reinforcing member 134, and the T-shaped reinforcing member 135 to the length of the cover plate 12 is set to 1 or less. That is, the length of the L-shaped reinforcing member 133, the C-shaped reinforcing member 134, and the T-shaped reinforcing member T135 is shorter than the length of the cover plate 12. Furthermore, the width of the contact area between the reinforcing member 13 and the exterior housing 11 is set to 1 mm to 10 mm in order to restrict the expansion of the cell 10 by the reinforcing member 13. Furthermore, the width of the L-shaped reinforcing member 133 on the cover plate 12 close to the explosion-proof valve 121 is (ab) / 2 or less, where a is the width of the cover plate 12 and b is the width of the explosion-proof valve 121, thereby preventing the L-shaped reinforcing member 133 from interfering with the explosion-proof valve 121. In some embodiments, the ratio of the height of the second surface 132 of the reinforcing member 13 to the height of the exterior housing 11 of the cell is greater than 3%, and the width of the first surface 131 of the reinforcing member 13 is greater than one tenth of the width of the cover plate. In this way, the reinforcing member 13 can be securely fixed to the cell 10, and the reliability of limiting the expansion of the cell 10 can be ensured.

[0039] 1 to 11, in this embodiment, an L-shaped reinforcing member 133 or a T-shaped reinforcing member 135 may be installed on one wide surface 111 of the exterior housing 11, or an L-shaped reinforcing member 133 or a T-shaped reinforcing member 135 may be installed on both of the two wide surfaces 111 of the exterior housing 11.

[0040] 5 to 7, in this embodiment, the C-shaped reinforcing member 134 further includes a third surface 137. The second surface 132 and the third surface 137 are located on both sides of the first surface 131, respectively, and are bent relative to the first surface 131. Preferably, the second surface 132 and the third surface 137 are both perpendicular to the first surface 137, and the third surface 137 and the second surface 132 face the two opposing wide surfaces 111 of the exterior housing 1, respectively. In addition, an avoidance groove 1311 is provided on the first surface 13, and the avoidance groove 1311 faces the explosion-proof valve 121 on the cover plate 12 so as to avoid the explosion-proof valve 121. Of course, in some other embodiments, the C-shaped reinforcing member 134 may be configured as a segmented structure. That is, the C-shaped reinforcing member 134 includes a plurality of segmented reinforcing members, and the plurality of segmented reinforcing members are spaced apart so as to avoid the explosion-proof valve 121. Additionally, the segmented reinforcing members can be installed to target critical areas of the weld between the cover plate 12 and the exterior housing 11, thereby providing effective protection for the housing cover weld.

[0041] 12 and 13, in this embodiment, each of the L-shaped reinforcing member 133 and the T-shaped reinforcing member 135 may be configured as a segmented structure. That is, the L-shaped reinforcing member 133 and the T-shaped reinforcing member 135 each include a plurality of segmented reinforcing members. The segmented reinforcing members can be installed to target critical areas of the weld between the cover plate 12 and the exterior housing 11, and can effectively protect the weld of the housing cover.

[0042] 14 and 15, in this embodiment, the annular reinforcing member 136 surrounds the welded portion between the exterior housing 11 and the cover plate 12 so as to encase the welded portion between the exterior housing 11 and the cover plate 12, thereby limiting the relative displacement between the exterior housing 11 and the cover plate 12, preventing the welded portion from being damaged during cycling, and effectively protecting the welded portion of the housing cover. For example, the annular reinforcing member 136 includes a first surface 131, a second surface 132, a third surface 137, and two opposing fourth surfaces 138. Here, the second surface 132 and the third surface 137 are located on both sides of the first surface 131, respectively, the fourth surface 138 is located on the other two sides of the first surface 131, and the second surface 132, the third surface 137, and the fourth surface 138 are bent relative to the first surface 131. Preferably, the second surface 132, the third surface 137, and the fourth surface 138 are each perpendicular to the first surface 131, and the first surface 131 is fixedly connected to the cover plate 12. The third surface 137 and the second surface 132 face two opposing wide surfaces 111 of the exterior housing 11, respectively. The two opposing fourth surfaces 138 face two opposing narrow surfaces 112 of the exterior housing 11, respectively, so that the relative displacement of the exterior housing 11 and the cover plate 12 is limited and the welded portion of the housing cover is effectively protected.

[0043] After the reinforcing member 13 is welded, the reinforcing member 13 occupies the surrounding space on the side and top of the original cell, i.e., the reinforcing member 13 occupies the space on the side and top of the original cell. The raised portion forms multiple outer surfaces, which makes it more difficult to apply insulation, and the conventional top patch, insulationThe film structure and bonding method are no longer applicable. The body or part of the reinforcing member is exposed, and an external insulation exposed point is formed, so that the risk of external short circuit is greatly increased, which affects the insulation performance of the cell. In particular, the difficulty of applying an insulating film to the side of the reinforcing member 13 is greatly increased. Therefore, an avoidance area 141 is provided on the top patch 14, specifically, a groove is provided on the side of the top patch 14 close to the reinforcing member 13 to form the avoidance area 141. For example, the groove is formed by partially cutting out one side of the top patch 14 close to the reinforcing member 13. The shape of the groove corresponds to the shape of the part of the reinforcing member 13 that is provided on the cover plate 12, and an insulating layer is added to the reinforcing member 13 to ensure the insulation performance. In some other embodiments, the avoidance area 141 can also be formed by performing a heat press corresponding to a local area of ​​the top patch 14 close to one side of the reinforcing member 13 to form a protrusion.

[0044] 16 to 19, in this embodiment, the portion of the reinforcing member 13 that is installed on the cover plate 12 is located in the avoidance area 141. For example, the reinforcing member 13 is an L-shaped reinforcing member 133, and the portion of the L-shaped reinforcing member 133 that is installed on the cover plate 12 is located in the avoidance area 141. Furthermore, in order to solve the problem of aluminum being exposed at one side end of the upper cover due to welding of the reinforcing member 13, an insulating layer is installed on the surface of the reinforcing member 13, so that a good external insulation effect is obtained and the external insulation performance of the battery is ensured. Specifically, the insulating layer may be provided as a heat-shrinkable sleeve film 151. The heat-shrinkable sleeve film 151 surrounds the upper part of the cell 10 and covers the surface of the reinforcing member 13. The heat-shrinkable sleeve film 151 is attached to the upper periphery of the cell 10 by heat shrinking, covers the upper patch 14, and achieves insulation protection.

[0045] 20 to 23, in another embodiment, the insulating layer is an insulating tape 15 2 The insulating tape 15 may be made of any insulating material and is attached to the surface of the reinforcing member 13. of 2Both ends protrude from both ends of the reinforcing member 13, and the parts protruding from the reinforcing member 13 are folded to cover the side surfaces of the reinforcing member 13. Note that the side surfaces of the reinforcing member 13 will have a special shape when the insulating film is attached. It is difficult to form the insulating film all at once, and exposed areas are likely to occur, increasing the risk of insulation. Therefore, in this embodiment, insulating tape 15 of 2 When the portion protruding from the reinforcing member 13 is folded to cover the side surface of the reinforcing member 13, the curved portion 153 of the side surface of the reinforcing member 13 is covered with two layers of insulating tape 15 so that the insulating layer more reliably and completely covers the exposed surface of the reinforcing member 13. 2nd prize Thus, an insulating material having a good external heat insulation effect can be obtained.

[0046] In some other embodiments, after the reinforcing member 13 is processed and formed, the surface of the reinforcing member 13 is made insulating by adding a heat shrink sleeve, dipping in one piece, spraying an insulating material, etc. As mentioned above, after the reinforcing member 13 is welded, an insulating layer can be applied to its exposed surface to further improve the external insulating effect.

[0047] 24 to 31, the present invention further provides a battery module. The battery module 100 includes a housing body 110, a cell stack 120, and a reinforcing member 13. The cell stack 120 is installed in the housing body 110 and is formed by stacking a plurality of cells 10. In the battery module 10, the outermost part of the cell stack 120 is Located in The expansion of the outer surfaces of the two cells 10 is most noticeable. Located in The relative displacement between the cover plates 12 located on the outer sides of the two cells 10 is relatively large, so the welds at this location are most likely to break during the cyclic expansion process. Therefore, in this embodiment, the reinforcing member 13 is provided at the outermost part of the cell stack 120. Located inThe reinforcing member 13 is disposed at least outside the two cells 10. The two outermost cells 10 refer to the two cells 10 located on both sides of the cell stack 120, and the outside of the cells 10 refers to the wide surface 111 of the cells adjacent to the housing body 110. In other embodiments, a reinforcing member 13 may be disposed in each cell 10. Referring to FIGS. 1 to 23, in this embodiment, each reinforcing member 13 may be any one of an L-shaped reinforcing member 133, a C-shaped reinforcing member 134, a T-shaped reinforcing member 135, and an annular reinforcing member 136.

[0048] Referring to FIG. 24, in this embodiment, the cell stack 120 includes a plurality of single cell groups. Each single cell group includes at least one cell 10, and the single cell groups are connected in series or in parallel. In this embodiment, the number of single cell groups is preferably an even number, and the plurality of single cell groups are preferably connected in series. In other words, the cell stack is formed by connecting an even number of cells 10 in series, and the positive electrodes and negative electrodes of the even number of cells 10 connected in series are alternately installed. Here, the reinforcing member 13 is preferably an L-shaped reinforcing member 133 or a T-shaped reinforcing member 135. Here, the outermost part of the cell stack 120 Located in The two cells 10 are completely identical and can share a single production line for production. Furthermore, the reinforcing member 13 requires minimal consumable material, and therefore the reinforcing member 13 can effectively protect the welded part of the housing cover and protect the expanded cell while also reducing its manufacturing cost.

[0049] Referring to FIG. 25, in this embodiment, the reinforcing member 13 may be installed on two cells 10 located on both sides of each single cell group. The multiple cells 10 in each single cell group are connected in series or parallel. For example, taking a single cell group including two cells 10 stacked on each other as an example, the reinforcing member 13 is installed on the distant sides of the two cells 10 in the single cell group, and the reinforcing member 13 is preferably an L-shaped reinforcing member 133. In some other embodiments, one T-shaped reinforcing member 135 is installed on the close sides of two adjacent single cell groups. That is, since the T-shaped reinforcing member 135 is located between the two adjacent cells 10 in the two adjacent single cell groups, the one T-shaped reinforcing member 135 can simultaneously restrict the outward expansion of the two cells 10.

[0050] 26, in some other embodiments, when the total number of cells in the multiple single-cell groups is an odd number, that is, when the number of cells 10 in the cell stack 120 is an odd number, or when the number of cells 10 is set to an even number and the positive and negative electrodes of the multiple cells 10 are installed on the same side, the reinforcing member 13 is preferably a C-shaped reinforcing member 134 or an annular reinforcing member 136. Here, the outermost Located in The two cells 10 are completely identical and can share a single production line for production. Therefore, the reinforcing member 13 can effectively protect the welded part of the housing cover and protect the expanded cell while reducing the manufacturing cost. In this embodiment, when multiple cells 10 are connected in series, it is preferable that the positive electrodes and negative electrodes of the multiple cells 10 are alternately installed. When multiple cells 10 are connected in parallel, it is preferable that the positive electrodes and negative electrodes of the multiple cells 10 are installed on the same side.

[0051] The present invention further provides a battery pack including the above-mentioned cell or the above-mentioned battery module.

[0052] The present invention provides a cell, a battery module, and a battery pack. The problem of cycle cracking caused by insufficient strength of the welded portion is solved by installing a reinforcing member in the cell. Furthermore, the relative displacement between the cell's housing body and the upper cover is limited, so that the welded portion is not damaged during cycling, the housing cover's welded portion is effectively protected, and the expanded cell is protected. Furthermore, the reinforcing member is connected to the cover plate and the housing body by laser welding or bonding, so that no separate device is required and the work is easy and efficient.

[0053] The present invention provides a cell, a battery module and a battery pack, in which the upper cover patch is provided with a workaround design, and the reinforcing member is coated and covered to solve the problem of aluminum exposure at one end of the upper cover caused by welding the reinforcing member, thereby achieving a good external insulation effect and ensuring the external insulation performance of the cell.

[0054] The present invention provides a cell, a battery module, and a battery pack. Located in By installing reinforcing members on at least the outside of the two cells, the safety of the battery module is improved by preventing the relative displacement between the housing body of the outermost cell and the top cover from causing the welds to burst during the expansion cycle of the cells.

[0055] The present invention provides a cell, a battery module, and a battery pack. When a cell stack includes an even number of cells, and the positive and negative electrodes of each cell are alternately arranged, the L-shaped reinforcing member is disposed on the outermost side of the cell stack. Located in Only the outer two cells are installed. In this way, the welds are prevented from breaking during the cell expansion cycle. Furthermore, if the number of cells is even, the outermost Located in Since the two cells are completely identical, only one production line is needed to manufacture the cell with the reinforcing member, which can effectively reduce the production cost.

[0056] In the above embodiment, "multiple" includes two or more. Furthermore, in the embodiment, a specific surface of the reinforcing member "facing" the cover plate or the exterior housing means that the specific surface of the reinforcing member is located on the cover plate along a protrusion perpendicular to the cover plate, or that the specific surface of the reinforcing member is located on the wide or narrow surface of the exterior housing along a projection perpendicular to the wide or narrow surface of the exterior housing. For example, "a second surface facing the wide surface of the exterior housing" means that the second surface of the reinforcing member is located on the wide surface along a projection perpendicular to the wide surface.

[0057] The above description is merely a preferred embodiment of the present invention, and illustrates the technical principles applied. Those skilled in the art should understand that the scope of the present invention is not limited to the technical solution formed by a specific combination of the above technical features, but also includes other technical solutions formed by any combination of the above technical features. For example, the technical solutions formed by replacing the above features with the technical features disclosed in the present invention having similar functions (but not limited thereto) shall also be included in the scope of the present invention.

[0058] Except for the technical features in this specification, the remaining technical features are well known to those skilled in the art. In order to highlight the innovative features of the present invention, the remaining technical features will not be repeated here. [Industrial Applicability]

[0059] The cell, battery module and battery pack of the present invention can be applied to the field of new energy vehicles. [Explanation of symbols]

[0060] 10: Cell 11: Exterior housing 12: Lid plate 13: Reinforcement member 131: First Surface 132: Second Surface 111: Large Surface 112: Narrow Surface 133: L-shaped reinforcement member 134: C-shaped reinforcement member 135: T-shaped reinforcement member 136: Circular reinforcement member 1351: Wing Plate 1352: Subplate 121: Explosion-proof valve 137: The Third Surface 1311: Avoidance groove 138: The Fourth Surface 14: Top patch 141: Avoidance area 151: Heat shrinkable sleeve film 152: Electrical tape 100: Battery module 110: Main unit 120: Cell Stack

Claims

1. An exterior housing; a cover plate welded to an upper portion of the exterior housing; a reinforcing member including at least a first surface and a second surface; the first surface is fixedly connected to one of the cover plate and the exterior housing; The second surface is a cell that faces the other of the cover plate and the exterior housing.

2. The cell further includes an electrode assembly stacked within the exterior housing in a thickness direction, a length direction, or a height direction of the cell; When the electrode assembly is stacked in the thickness direction, the first surface is fixedly connected to the cover plate, and the second surface faces a large surface of the exterior housing; When the electrode assemblies are stacked in the longitudinal direction, the first surface is fixedly connected to the cover plate, and the second surface faces a narrow surface of the exterior housing; When the electrode assemblies are stacked in a height direction, the first surface is fixedly connected to the exterior housing, and the second surface faces the cover plate. The cell of claim 1 .

3. The reinforcing member is an L-shaped reinforcing member, a C-shaped reinforcing member, a T-shaped reinforcing member, or an annular reinforcing member; The cell of claim 2.

4. The ratio of the length of each of the L-shaped reinforcing member, the C-shaped reinforcing member, and the T-shaped reinforcing member to the length of the cover plate is 1 or less. The cell of claim 3.

5. The width of the L-shaped reinforcing member on the cover plate close to the explosion-proof valve is (a-b) / 2 or less, where a is the width of the cover plate and b is the width of the explosion-proof valve; The cell of claim 3.

6. each of the L-shaped reinforcement member, the C-shaped reinforcement member, and the T-shaped reinforcement member includes a plurality of segmented reinforcement members, the plurality of segmented reinforcement members being spaced apart; The cell of claim 3.

7. The C-shaped reinforcing member further includes a third surface, the third surface and the second surface respectively facing two opposing broad surfaces of the exterior housing, and an avoidance groove is provided on the first surface, the avoidance groove facing the explosion-proof valve of the cover plate; The cell of claim 3.

8. The cell further includes an upper patch, a groove is provided on a side of the upper patch close to the reinforcing member to form an avoidance area, and a part of the reinforcing member provided on the cover plate is located in the avoidance area. The cell of claim 1 .

9. Further comprising an insulating layer comprising a heat shrinkable sleeve film, an insulating tape, or a blue film; the heat-shrinkable sleeve film surrounds the upper portion of the cell and covers a surface of the reinforcing member; The insulating tape or the blue film is attached to the surface of the reinforcing member. The cell of claim 8.

10. Both ends of the insulating tape or the blue film protrude from both ends of the reinforcing member, and the portions protruding from the reinforcing member are folded to cover the side surfaces of the reinforcing member. The cell of claim 9.

11. A housing body, A cell stack including a plurality of cells; a reinforcing member provided on at least the outside of the two outermost cells of the cell stack; Each of the cells includes an exterior housing and a cover plate welded to an upper portion of the exterior housing; Each of the reinforcing members includes at least a first surface and a second surface, the first surface being fixedly connected to one of the cover plate and the exterior housing, and the second surface facing the other of the cover plate and the exterior housing.

12. The reinforcing member is provided in each of the cells. The battery module according to claim 11.

13. The cell stack includes an even number of single cell groups, each of the single cell groups including at least one of the cells, and the single cell groups are connected in series. The battery module according to claim 11.

14. The cell stack includes a plurality of single cell groups, and the reinforcing member is installed on the two cells located on both sides of each of the single cell groups. The battery module according to claim 11.

15. A T-shaped reinforcing member is installed on each of two adjacent groups of single cells, the T-shaped reinforcing member including a wing plate, a sub-plate, two first surfaces, and two second surfaces, the two second surfaces being installed on both sides of the sub-plate respectively, and the two first surfaces being installed on the bottom of the wing plate on both sides of the sub-plate respectively. The battery module according to claim 13.

16. A T-shaped reinforcing member is installed on each of two adjacent groups of single cells, the T-shaped reinforcing member including a wing plate, a sub-plate, two first surfaces, and two second surfaces, the two second surfaces being installed on both sides of the sub-plate respectively, and the two first surfaces being installed on the bottom of the wing plate on both sides of the sub-plate respectively. The battery module according to claim 14.

17. A battery pack comprising the battery according to any one of claims 1 to 10.

18. A battery pack comprising the battery module according to any one of claims 11 to 16.

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