Battery cell and battery pack

Abstract

The utility model relates to new energy battery technical field discloses a battery monomer and battery package have first direction, and battery monomer includes: casing, including bottom plate and side plate, electrode assembly includes main part, and the main part has the first wall opposite setting with bottom plate along first direction, insulating film includes bottom surface film and side surface film, and the electrode assembly is enclosed and covered, and the bottom surface film has the perforation along first direction, bottom support plate is located between bottom surface film and bottom plate, and the bottom support plate includes the plate body and the boss, and the boss is located in the side of plate body and is away from bottom plate along first direction, and the plate body is connected with bottom surface film, and the boss is worn in the perforation and supports the first wall. The boss of bottom support plate supports the first wall of main part after wearing the perforation along first direction, plays the role of supporting and fixing electrode assembly, can reduce the swing of electrode assembly in accommodating cavity under the vibration working condition, avoids the abrasion caused by the direct contact of electrode assembly and bottom plate, improves the safety and stability of battery monomer.

Description

Technical Field

[0001] This utility model relates to the field of new energy battery technology, and in particular to a battery cell and battery pack. Background Technology

[0002] Existing battery cells typically include a housing, electrode assembly, current collector, terminal assembly, and insulating components. The electrode assembly is arranged inside the housing, the terminal assembly is fixed to the housing, the current collector electrically connects the electrode assembly and the terminal assembly, and the insulating component covers the electrode assembly to insulate and isolate it from the housing. The electrode assembly includes a main body and tabs. The main body is formed by winding electrode sheets, diaphragms, etc., and includes flat areas and curved areas. Typically, the electrode assembly is placed upright inside the housing, with its bottom surface supported by the housing.

[0003] Due to size constraints, some battery cells have their electrode assemblies placed sideways inside the casing, with the curved area of ​​the electrode assembly's main body supported by the casing. In this case, the electrode assembly relies primarily on the curved area and insulation components for support, resulting in poor fixation. Under vibration conditions, the electrode assembly will sway within the casing, affecting the safety of the individual battery cells. Utility Model Content

[0004] The purpose of this invention is to provide a single battery cell to solve the problem of electrode assembly shaking under vibration conditions in the prior art; this invention also provides a battery pack using this single battery cell.

[0005] To achieve the above objectives, this utility model provides a battery cell having a first orientation, the battery cell comprising: The housing includes a bottom plate and a side plate connected together, the bottom plate and the side plate enclosing a receiving cavity; An electrode assembly is disposed in the receiving cavity. The electrode assembly includes a main body portion, the main body portion having a first wall disposed opposite to the base plate along a first direction. An insulating film includes a bottom film and a side film connected together, the bottom film and the side film surrounding and covering the electrode assembly, the bottom film having a perforation extending through the first direction; A bottom support plate is disposed between the bottom film and the bottom plate along the first direction. The bottom support plate includes a plate body and a boss connected to each other. The boss is disposed on the side of the plate body away from the bottom plate along the first direction. The plate body is connected to the bottom film. The boss passes through the perforation and supports the first wall.

[0006] In some embodiments, the insulating film further includes a support frame disposed on the side of the bottom film away from the plate body along the first direction, the support frame is connected to the bottom film, and the support frame has a support surface that supports the first wall.

[0007] In some embodiments, the first wall is an arc surface, the support frame is provided with a groove with an arc cross-section, the groove wall forms the support surface, and the support surface is in contact with the first wall.

[0008] In some embodiments, the boss has a second wall away from the plate body along the first direction, and the plate body has a third wall close to the main body along the first direction. The second wall and the third wall are parallel planes. Along the first direction, the minimum distance between the support surface and the third wall is H, and the minimum distance between the second wall and the third wall is L, satisfying: H=L.

[0009] In some embodiments, the battery cell further has a second direction perpendicular to the first direction, and at least two support frames are spaced apart along the second direction, with the support frames provided on both sides of the boss along the second direction.

[0010] In some embodiments, a first gap exists between the support frame and the boss along the second direction.

[0011] In some embodiments, the battery cell further includes a cover plate, a terminal post, a lead, and insulating tape. The electrode assembly further includes a tab connected to the main body. The tab is disposed between the main body and the side plate. The cover plate seals the receiving cavity and is fixedly connected to the side plate. The terminal post is fixedly connected to the cover plate. The lead is electrically connected to the terminal post and the tab. The insulating tape covers the lead and the tab.

[0012] In some embodiments, the battery cell further includes a fixing adhesive tape, which fixes the side plate to the side film.

[0013] In some embodiments, a buffer member is further included, which is disposed on the side of the side membrane close to the side plate along a second direction. The buffer member is fixedly connected to the side membrane, and the second direction is perpendicular to the first direction.

[0014] This utility model also provides a battery pack, including the battery cells described in any of the above technical solutions.

[0015] Compared with the prior art, the battery cell and battery pack of this utility model embodiment have the following advantages: an insulating film formed by a bottom film and a side film is provided between the electrode assembly and the housing. The bottom film and the side film can insulate and isolate the housing and the electrode assembly, thereby improving the insulation of the battery cell. The bottom film is provided with perforations, and the boss of the bottom support plate supports the first wall of the main body after the perforations are provided along the first direction, which plays the role of supporting and fixing the electrode assembly. This can reduce the shaking of the electrode assembly in the cavity under vibration conditions, avoid the electrode assembly directly contacting the bottom plate and causing wear, and improve the safety and stability of the battery cell. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a single battery cell of this utility model; Figure 2 yes Figure 1 A cross-sectional view of a single battery cell; Figure 3 yes Figure 1 A schematic diagram of the insulating film structure of a single battery cell; Figure 4 yes Figure 3 A three-dimensional structural diagram of the insulating film from another perspective; Figure 5 This is a schematic diagram of the structure of the battery cell after the insulating film and the base plate are assembled. Figure 6 yes Figure 5 A top view of the insulating film and the base plate after assembly; Figure 7 yes Figure 6 A cross-sectional view of the insulating film and the base plate after assembly; Figure 8 yes Figure 7 Front view of the insulating film and base plate after assembly; Figure 9 yes Figure 8 An enlarged schematic diagram of point A after the insulating film and the base plate are assembled.

[0017] In the figure, 1. Shell, 11. Base plate, 12. Side plate, 13. Receiving cavity, 2. Electrode assembly, 21. Main body, 211. First wall, 22. Electrode tab, 3. Insulating film, 31. Bottom film, 32. Side film, 33. Perforation, 34. Support frame, 341. Support surface, 342. Groove, 343. Groove wall, 4. Bottom support plate, 41. Plate body, 411. Third wall, 42. Boss, 421. Second wall, 5. Cover plate, 6. Electrode post, 7. Pin, 8. Insulating tape, 9. Fixing tape, 10. Buffer, 20. First gap, 30. Second gap, Z. First direction, Y. Second direction. Detailed Implementation

[0018] The specific embodiments of this utility model will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this utility model, but are not intended to limit its scope.

[0019] A preferred embodiment of a battery cell of this utility model is as follows: Figures 1 to 9 As shown, the battery cell includes a housing 1, an electrode assembly 2, an insulating film 3, and a base plate 4, all of which are disposed within the housing 1. The battery cell also has a first direction Z and a second direction Y that are perpendicular to each other. In this embodiment, the battery cell is a square battery, the first direction Z is the height direction of the battery cell, and the second direction Y is the width direction of the battery cell.

[0020] The housing 1 is a square, thin-walled structure with an open top. The housing 1 includes a bottom plate 11 and side plates 12, which are fixedly connected. The bottom plate 11 is a rectangular plate, and there are four side plates 12, each connected to one of the four sides of the bottom plate 11. The bottom plate 11 and the side plates 12 together form a receiving cavity 13. The receiving cavity 13 is a cuboid cavity, and the electrode assembly 2, the insulating film 3, and the base plate 4 are all disposed within the receiving cavity 13. The housing 1 provides protection for the electrode assembly 2, the insulating film 3, and the base plate 4 within the receiving cavity 13.

[0021] like Figure 1 and Figure 2 As shown, the electrode assembly 2 includes a main body 21, which is formed by winding positive electrode sheets, negative electrode sheets, etc. The main body 21 has a first wall 211, which is disposed opposite to the base plate 11 along the first direction Z. In this embodiment, the first wall 211 is a curved surface.

[0022] like Figure 1 , Figure 3 and Figure 4 As shown, the insulating film 3 includes a bottom film 31 and side films 32, which are connected to each other. The bottom film 31 and the bottom plate 11 are disposed opposite each other along the first direction Z. The bottom film 31 is a rectangular film, and the side films 32 are fixedly connected to each side of the bottom film 31. In this embodiment, the bottom film 31 and the side films 32 are integrally formed. The bottom film 31 and the side films 32 surround and cover the electrode assembly 2, which can insulate and isolate the electrode assembly 2 from the shell 1, thereby improving the insulation of the battery cell. The bottom film 31 also has a perforation 33, which penetrates the bottom film 31 along the first direction Z. In this embodiment, the perforation 33 is a rectangular hole, located at the center of the bottom film 31 along the second direction Y. The side films 32 are fixed to the main body 21 of the electrode assembly 2 by adhesive backing.

[0023] like Figure 1As shown, the bottom support plate 4 is disposed between the bottom film 31 and the bottom plate 11 along the first direction Z. The bottom support plate 4 includes a plate body 41 and a boss 42. The plate body 41 is a rectangular plate, and the boss 42 is connected to the plate body 41. The boss 42 is located on the side of the plate body 41 facing away from the bottom plate 11 along the first direction Z. The plate body 41 is connected to the bottom film 31. In this embodiment, the plate body 41 and the boss 42 are integrally formed. The boss 42 is located on the side of the plate body 41 facing away from the bottom plate 11 along the second direction Y. The bottom film 31 and the plate body 41 are heat-fused and fixedly connected.

[0024] like Figure 6 , Figure 7 As shown, the boss 42 is inserted into the perforation 33 along the first direction Z, and the boss 42 supports the first wall 211 to support the electrode assembly 2 along the first direction Z, thereby reducing the vertical sway of the electrode assembly 2. In this embodiment, the boss 42 and the wall of the perforation 33 have a second gap 30 along the second direction Y, which can prevent the boss 42 from squeezing the insulating film 3.

[0025] The battery cell has an insulating film 3 formed by a bottom film 31 and a side film 32 between the electrode assembly 2 and the housing 1. The bottom film 31 and the side film 32 can insulate and isolate the housing 1 and the electrode assembly 2, thereby improving the insulation of the battery cell. The bottom film 31 is provided with a perforation 33. The boss 42 of the bottom support plate 4 passes through the perforation 33 along the first direction Z and supports the first wall 211 of the main body 21, which plays the role of supporting and fixing the electrode assembly 2. This can reduce the shaking of the electrode assembly 2 in the receiving cavity 13 under vibration conditions, and prevent the electrode assembly 2 from directly contacting the bottom plate 11 and causing wear, thereby improving the safety and stability of the battery cell.

[0026] In some embodiments, the insulating film 3 further includes a support frame 34, which is disposed on the side of the bottom film 31 away from the plate 41 along the first direction Z. The support frame 34 is connected to the bottom film 31 and has a support surface 341 that supports the first wall 211.

[0027] like Figure 3 and Figure 4 As shown, the support frame 34 of the insulating film 3 is connected to the bottom film 31. The support surface 341 of the support frame 34 supports the first wall 211 of the main body 21 along the first direction Z and supports the electrode assembly 2 along the first direction Z, reducing the vibration of the electrode assembly 2 along the first direction Z. The support frame 34 of the insulating film 3 cooperates with the boss 42 of the bottom support plate 4, which can further reduce the vibration amplitude of the electrode assembly 2 and avoid direct contact between the electrode assembly 2 and the bottom support plate 4 and the bottom plate 11, causing wear. In this embodiment, the support frame 34 and the insulating film 3 are integrally formed. In other embodiments, the support frame 34 and the insulating film 3 can also be separate structures, connected by heat fusion.

[0028] In some embodiments, the first wall 211 is an arc surface, and the support frame 34 is provided with a groove 342 with an arc cross-section. The groove wall 343 of the groove 342 forms a support surface 341, and the support surface 341 is in contact with the first wall 211.

[0029] like Figure 2 , Figure 4 As shown, under normal circumstances, the first wall 211 of the main body 21, formed by winding positive and negative electrode sheets, is an arc surface. The support frame 34 is provided with an arc-shaped groove 342 so that the groove wall 343 of the groove 342 fits against the first wall 211, thereby supporting the electrode assembly 2. This can increase the contact area between the first wall 211 and the support surface 341, improve the stability of the electrode assembly 2, and prevent the electrode assembly 2 from being loose and shedding powder at the position of the support frame 34, thus ensuring the performance of the battery cell.

[0030] In some embodiments, the boss 42 has a second wall 421 that is away from the plate 41 along the first direction Z, and the plate 41 has a third wall 411 that is close to the main body 21 along the first direction Z. The second wall 421 and the third wall 411 are mutually parallel planes. Along the first direction Z, the minimum distance between the support surface 341 and the third wall 411 is H, and the minimum distance between the second wall 421 and the third wall 411 is L, satisfying: H=L.

[0031] like Figure 8 and Figure 9 As shown, the second wall 421 of the boss 42 is a plane, and the second wall 421 supports the first wall 211 of the main body 21 along the first direction Z. The use of a plane for the second wall 421 simplifies the structure of the boss 42 of the base plate 4. Since both the second wall 421 and the support surface 341 support the first wall 211 along the first direction Z, when the minimum distance H between the support surface 341 and the third wall 411 is equal to the minimum distance L between the second wall 421 and the third wall 411, the lowest point of the support surface 341 and the second wall 421 are aligned along the first direction Z, making the boss 42 and the support frame 34 aligned with the support points of the electrode assembly 2, thus ensuring the stability of the electrode assembly 2.

[0032] In other embodiments, the second wall 421 may also be an arc surface, with the second wall 421 having the same radius as the first wall 211, and the second wall 421 being completely fitted to the first wall 211, which can increase the contact area between the second wall 421 and the first wall 211.

[0033] In some embodiments, the battery cell also has a second direction Y that is perpendicular to the first direction Z, and at least two support frames 34 are provided at intervals along the second direction Y. The boss 42 is provided with support frames 34 on both sides along the second direction Y.

[0034] like Figure 4 , Figure 6 , Figure 7 and Figure 8 As shown, there are at least two support frames 34. The number of support frames 34 can be increased according to the size of the battery cell along the second direction Y. Each support frame 34, arranged along the second direction Y, supports the electrode assembly 2, increasing the support surface area 341 of the support frame 34 and improving the stability of the electrode assembly 2. In this embodiment, there are two support frames 34, spaced apart along the second direction Y, which also prevents the support frames 34 from squeezing the electrode assembly 2. In this embodiment, the second direction Y is the width direction of the battery cell.

[0035] In some embodiments, a first gap 20 is provided between the support frame 34 and the boss 42 along the second direction Y.

[0036] like Figure 8 As shown, there is a first gap 20 between the support frame 34 and the boss 42 along the second direction Y. This gap ensures that the support frame 34 and the boss 42 jointly support the electrode assembly 2, ensuring the stability of the electrode assembly 2. At the same time, it also prevents the support frame 34 from causing local compression to the electrode assembly 2, thus ensuring the electrical performance of the electrode assembly 2.

[0037] In some embodiments, the battery cell further includes a cover plate 5, a terminal post 6, a lead 7, and an insulating tape 8. The electrode assembly 2 further includes a tab 22 connected to the main body 21. The tab 22 is disposed between the main body 21 and the side plate 12. The cover plate 5 covers the receiving cavity 13 and is fixedly connected to the side plate 12. The terminal post 6 is fixedly connected to the cover plate 5. The lead 7 is electrically connected to the terminal post 6 and the tab 22. The insulating tape 8 covers the lead 7 and the tab 22.

[0038] like Figure 1 and Figure 2 As shown, after the cover plate 5 is fixedly connected to the side plate 12, it seals the receiving cavity 13, which can protect the electrode assembly 2 and other components inside the receiving cavity 13, and at the same time prevent electrolyte leakage. The tabs 22 are arranged between the main body 21 and the side plate 12 along the second direction Y. There are two tabs 22, which are located on both sides of the main body 21 along the second direction Y. The main body 21 and the side plate 12 are spaced apart to accommodate the tabs 22.

[0039] Pin 7 is electrically connected to electrode post 6 and electrode tab 22, and then externally covered with insulating tape 8. The insulating tape 8 can support and fix both ends of electrode assembly 2 in the second direction Y, improving the stability of electrode assembly 2. In this embodiment, electrode tab 22 and pin 7 are fixed by ultrasonic welding.

[0040] In some embodiments, the battery cell further includes a fixing adhesive tape 9, which fixes the side plate 12 and the side film 32.

[0041] like Figure 1As shown, the fixing tape 9 securely connects the side plate 12 of the housing 1 to the side film 32 of the insulating film 3, fixing the insulating film 3 and improving the stability of the insulating film 3 inside the housing 1. In this embodiment, the fixing tape 9 is an insulating component.

[0042] In some embodiments, a buffer 10 is also included. The buffer 10 is disposed on the side of the side membrane 32 along the second direction Y near the side plate 12. The buffer 10 is fixedly connected to the side membrane 32. The second direction Y is perpendicular to the first direction Z.

[0043] like Figure 1 As shown, a buffer 10 is provided on the side film 32. When the electrode assembly 2 shakes along the second direction Y, the buffer 10 can provide a buffering force for the electrode assembly 2, preventing the pins 7 from directly rubbing against the side plate 12 of the housing 1, thereby improving the stability and stability of the electrode assembly 2. In this embodiment, the buffer 10 is made of mica material, and the buffer 10 is fixed to the side film 32 by heat fusion or adhesive backing. In this embodiment, the second direction Y is the width direction of the battery cell.

[0044] A preferred embodiment of the battery pack of this utility model includes a battery cell, the specific structure of which is the same as that of the battery cell described in any of the above embodiments, and will not be repeated here.

[0045] In summary, this utility model embodiment provides a battery cell and a battery pack, in which an insulating film formed by a bottom film and a side film is provided between the electrode assembly and the housing. The bottom film and the side film can insulate and isolate the housing and the electrode assembly, thereby improving the insulation of the battery cell. The bottom film is provided with perforations, and the boss of the bottom support plate supports the first wall of the main body after passing through the perforations along the first direction, which plays the role of supporting and fixing the electrode assembly. This can reduce the shaking of the electrode assembly in the receiving cavity under vibration conditions, avoid the electrode assembly directly contacting the bottom plate and causing wear, and improve the safety and stability of the battery cell.

[0046] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present utility model, and these improvements and substitutions should also be considered within the protection scope of the present utility model.

Claims

1. A battery cell, characterized in that, Having a first orientation, the battery cell includes: The housing includes a bottom plate and a side plate connected together, the bottom plate and the side plate enclosing a receiving cavity; An electrode assembly is disposed in the receiving cavity. The electrode assembly includes a main body portion, the main body portion having a first wall disposed opposite to the base plate along a first direction. An insulating film includes a bottom film and a side film connected together, the bottom film and the side film surrounding and covering the electrode assembly, the bottom film having a perforation extending through the first direction; A bottom support plate is disposed between the bottom film and the bottom plate along the first direction. The bottom support plate includes a plate body and a boss connected to each other. The boss is disposed on the side of the plate body away from the bottom plate along the first direction. The plate body is connected to the bottom film. The boss passes through the perforation and supports the first wall.

2. The battery cell according to claim 1, characterized in that, The insulating film also includes a support frame, which is disposed on the side of the bottom film away from the plate body along the first direction. The support frame is connected to the bottom film and has a support surface that supports the first wall.

3. The battery cell according to claim 2, characterized in that, The first wall is an arc surface, and the support frame has a groove with an arc-shaped cross-section. The groove wall forms the support surface, and the support surface fits against the first wall.

4. The battery cell according to claim 3, characterized in that, The boss has a second wall that is away from the plate along the first direction, and the plate has a third wall that is close to the main body along the first direction. The second wall and the third wall are parallel planes. Along the first direction, the minimum distance between the support surface and the third wall is H, and the minimum distance between the second wall and the third wall is L, satisfying: H=L.

5. The battery cell according to claim 3, characterized in that, The battery cell also has a second direction perpendicular to the first direction, and at least two support frames are spaced apart along the second direction. The boss is provided with the support frame on both sides along the second direction.

6. The battery cell according to claim 5, characterized in that, Along the second direction, there is a first gap between the support frame and the boss.

7. The battery cell according to any one of claims 1-6, characterized in that, The battery cell also includes a cover plate, terminals, leads, and insulating tape. The electrode assembly also includes tabs connected to the main body. The tabs are located between the main body and the side plate. The cover plate seals the receiving cavity and is fixedly connected to the side plate. The terminals are fixedly connected to the cover plate. The leads are electrically connected to the terminals and the tabs. The insulating tape covers the leads and the tabs.

8. The battery cell according to any one of claims 1-6, characterized in that, The battery cell also includes a fixing adhesive tape, which fixes the side plate to the side film.

9. The battery cell according to any one of claims 1-6, characterized in that, It also includes a buffer member, which is disposed on the side of the side membrane along the second direction close to the side plate. The buffer member is fixedly connected to the side membrane, and the second direction is perpendicular to the first direction.

10. A battery pack, characterized in that, Includes the battery cell described in any one of claims 1-9.

Images