Battery cell and battery pack

Abstract

The utility model relates to the technical field of battery cells, and discloses a battery cell and a battery pack. The battery comprises a shell, a positive electrode cover plate and a negative electrode cover plate, the shell is provided with two open ends which are oppositely arranged, and at least one anti-explosion valve is arranged on the side wall of the shell; the positive electrode cover plate is arranged at one open end of the shell; the positive pole cover plate is provided with a convex positive pole post; the negative electrode cover plate is arranged at the other open end of the shell; the negative electrode cover plate is provided with a convex negative electrode post; and the positive pole of one battery cell is suitable for being conductively abutted against the negative pole of the other battery cell. According to the utility model, when the battery cell is subjected to thermal runaway, the thermal runaway pressure relief channel is separated from the circuit, so that the insulation design requirement on the battery cell can be reduced; according to the utility model, a connecting piece between the adjacent battery cells is omitted, a gap between the adjacent battery cells can be reduced, the overall space utilization rate and the overall integration degree of the battery pack are improved, and the overall cost of the battery pack can be saved due to the omission of the connecting piece.

Description

Technical Field

[0001] The utility model relates to the technical field of battery cells, in particular to battery cells and battery packs. Background Art

[0002] Energy density and safety are two major characteristics of battery cells that have attracted much attention.

[0003] In terms of safety, in order to prevent the battery cell from exploding during thermal runaway, traditional battery cells are equipped with explosion-proof valve devices on the cover. The opening pressure of the explosion-proof valve is lower than the pressure required for the battery cell shell to explode. When the internal pressure of the battery cell reaches the opening pressure of the explosion-proof valve, the explosion-proof valve will open first to relieve the pressure inside the battery cell.

[0004] In terms of energy density, in order to improve the energy density of the battery pack, people have designed the battery cells into long strips, which can be directly arranged in the battery pack, eliminating the link from battery cells to modules and improving space utilization.

[0005] Traditional long-cell explosion-proof valves and injection ports are located on the cell cover. In the event of thermal runaway, the hot gases and circuits share the same space, placing high demands on the cell's insulation design. Furthermore, traditional battery pack designs utilize modules, with large gaps between modules, reducing overall space utilization. Modules are connected via connectors such as copper busbars, which incurs significant costs. Utility Model Content

[0006] In view of this, the present invention provides a battery cell and a battery pack to solve the problem of high insulation design requirements for the battery cell or the problem of low space utilization of the battery pack as a whole.

[0007] In a first aspect, the present invention provides a battery cell comprising a housing, a positive electrode cover, and a negative electrode cover. The housing has two opposing open ends, and at least one explosion-proof valve is provided on the sidewall of the housing. The positive electrode cover is provided at one of the open ends of the housing and has a protruding positive electrode post. The negative electrode cover is provided at the other open end of the housing and has a protruding negative electrode post. The positive electrode post of one battery cell is adapted to electrically abut against the negative electrode post of the other battery cell.

[0008] Beneficial effects: The battery cell provided by the present invention has an explosion-proof valve disposed on the housing, a positive electrode post disposed on the positive cover plate, and a negative electrode post disposed on the negative cover plate. When thermal runaway occurs in the battery cell, the thermal runaway pressure relief channel is separated from the circuit, thereby reducing the insulation design requirements for the battery cell. Furthermore, since the positive electrode post of one battery cell can be in conductive contact with the negative electrode post of another battery cell, compared to conventional technical solutions, when the battery cells are connected in series to form a battery cell unit, the present invention omits the connectors between adjacent battery cells, thereby reducing the gaps between adjacent battery cells and improving the overall space utilization and integration of the battery pack. Furthermore, since the connectors are omitted, the overall cost of the battery pack can be saved.

[0009] In an optional embodiment, the positive electrode cover plate of one battery cell and the negative electrode cover plate of another battery cell are provided with an error-proofing structure.

[0010] In an optional embodiment, the anti-error structure includes an anti-error protrusion and an anti-error groove that are suitable for plugging into each other, the anti-error protrusion is provided on one of the positive pole and the negative pole, and the anti-error groove is provided on the other of the positive pole and the negative pole.

[0011] In an optional embodiment, the positive electrode pole includes a positive electrode pole body and a first boss protruding from the outer periphery of the positive electrode pole body; the negative electrode pole includes a negative electrode pole body and a second boss protruding from the outer periphery of the negative electrode pole body; the first boss of one battery cell is suitable for welding to the second boss of another battery cell; and the error-proofing structure is arranged between the first boss of one battery cell and the second boss of another battery cell.

[0012] In an optional embodiment, a heat absorbing member is provided in a first groove formed between the first boss and the positive electrode body; and / or a heat absorbing member is provided in a second groove formed between the second boss and the negative electrode body.

[0013] In an optional embodiment, the melting point of the heat absorbing element is not less than 60°C.

[0014] In an optional embodiment, the side walls of the first boss and / or the second boss are provided with a plurality of overflow holes, and the overflow holes are suitable for allowing the melted heat absorbing element to flow out.

[0015] In an optional embodiment, at least one thermal insulation sheet is further included, the thermal insulation sheet is provided with a through hole to avoid the positive electrode column or the negative electrode column, and the thermal insulation sheet is arranged on the outer surface of the positive cover plate and / or the negative cover plate.

[0016] In an optional embodiment, the thermal insulation sheet includes aerogel and / or double-sided tape.

[0017] In the second aspect, the utility model also provides a battery pack, comprising multiple battery cell units, each battery cell unit comprising multiple battery cells according to any one of the above technical solutions, wherein the positive pole of one battery cell and the negative pole of another battery cell of two adjacent battery cells in each battery cell unit are conductively abutted, and the two ends of the battery cell unit are the positive pole and the negative pole respectively; the positive pole of one battery cell unit and the negative pole of another adjacent battery cell unit are conductively connected through a bus.

[0018] Beneficial effects: Since the battery pack includes battery cells, it has the same effects as the battery cells and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 This is a schematic structural diagram of a battery cell according to an embodiment of the present invention from a first perspective;

[0021] Figure 2 for Figure 1 A partial enlarged view of the positive pole in the middle;

[0022] Figure 3 for Figure 1 Exploded view of the battery cell shown;

[0023] Figure 4 for Figure 3 A partial enlarged view of the positive pole in the middle;

[0024] Figure 5 for Figure 1 A schematic structural diagram of the battery cell from a second perspective is shown;

[0025] Figure 6 for Figure 5 A partial enlarged view of the middle negative pole;

[0026] Figure 7 for Figure 5 Exploded view of the battery cell shown;

[0027] Figure 8 for Figure 7 A partial enlarged view of the middle negative pole;

[0028] Figure 9 for the reason Figure 1 A schematic structural diagram of a battery cell unit composed of the battery cells shown;

[0029] Figure 10 for Figure 9 A partial enlarged view of point A in the middle;

[0030] Figure 11 for Figure 9 A partial enlarged view of point B in the middle;

[0031] Figure 12 for the reason Figure 9 The exploded view of the battery pack composed of battery cells is shown.

[0032] Description of reference numerals:

[0033] 1. Shell; 2. Positive cover; 21. Positive pole; 211. Positive pole body; 212. First boss; 3. Negative cover; 31. Negative pole; 311. Negative pole body; 312. Second boss; 41. Error-proofing protrusion; 42. Error-proofing groove; 5. Explosion-proof valve; 6. Heat absorber; 7. Overflow hole; 8. Thermal insulation sheet; 10. Battery cell; 20. Busbar; 30. Welding mark; 100. Battery cell unit; 200. Upper shell; 300. Lower shell; 1000. Battery pack. DETAILED DESCRIPTION

[0034] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0035] The following combination Figures 1 to 12 , describing the embodiments of the present utility model.

[0036] According to an embodiment of the present invention, in one aspect, a battery cell 10 is provided, comprising a housing 1, a positive electrode cover plate 2, and a negative electrode cover plate 3. The housing 1 has two opposing open ends, and at least one explosion-proof valve 5 is provided on the sidewall of the housing 1. The positive electrode cover plate 2 is provided at one of the open ends of the housing 1. The positive electrode cover plate 2 is provided with a protruding positive electrode post 21. The negative electrode cover plate 3 is provided at the other open end of the housing 1. The negative electrode cover plate 3 is provided with a protruding negative electrode post 31. The positive electrode post 21 of one battery cell 10 is adapted to electrically abut against the negative electrode post 31 of another battery cell 10.

[0037] In the battery cell 10 provided by the embodiment of the present invention, since the explosion-proof valve 5 is provided on the shell 1, the positive electrode column 21 is provided on the positive electrode cover 2, and the negative electrode column 31 is provided on the negative electrode cover 3, when thermal runaway occurs in the battery cell 10, the thermal runaway pressure relief channel is separated from the circuit, which can reduce the insulation design requirements for the battery cell 10.

[0038] In addition, since the positive electrode post 21 of one battery cell 10 can be conductively abutted against the negative electrode post 31 of another battery cell 10, compared with traditional technical solutions, when the battery cells 10 are connected in series into a battery cell unit 100, the present invention omits the connectors between adjacent battery cells 10, which can reduce the gap between adjacent battery cells 10, improve the overall space utilization and integration of the battery pack, and since the connectors are omitted, the overall cost of the battery pack can be saved.

[0039] Specifically, in some embodiments, the position of the positive electrode column 21 and the position of the negative electrode column 31 are set correspondingly. In this way, when two adjacent battery cells 10 are docked, the outer side walls of the two battery cells 10 are ensured to be flush, which is conducive to improving the battery grouping rate.

[0040] In some embodiments, the positive electrode cover plate 2 of one battery cell 10 and the negative electrode cover plate 3 of another battery cell 10 are provided with an error-proofing structure.

[0041] By setting up an error-proofing structure, technicians can quickly and accurately connect the positive cover plate 2 and the negative cover plate 3 when connecting two battery cells 10 in series, preventing poles of the same polarity from conductively abutting each other, thereby playing an error-proofing role in production.

[0042] In some embodiments, the anti-error structure includes an anti-error protrusion 41 and an anti-error groove 42 that are suitable for plugging into each other, the anti-error protrusion 41 is provided on one of the positive pole 21 and the negative pole 31, and the anti-error groove 42 is provided on the other of the positive pole 21 and the negative pole 31.

[0043] Specifically, in this embodiment, Figures 1 to 4 As shown, the positive electrode column 21 is provided with an anti-error protrusion 41, as shown in FIG. Figures 5 to 8 As shown, the negative electrode post 31 is provided with an anti-error groove 42. When the two battery cells 10 are arranged along the length direction, the positive electrode post 21 of one battery cell 10 and the negative electrode post 31 of the other battery cell 10 are abutted and connected in series, and the anti-error protrusion 41 on the positive electrode post 21 is inserted into the anti-error groove 42 on the negative electrode post 31, so that the two battery cells 10 can be quickly connected in series.

[0044] In some embodiments, the positive electrode post 21 includes a positive electrode post body 211 and a first boss 212 protruding from the outer periphery of the positive electrode post body 211; the negative electrode post 31 includes a negative electrode post body 311 and a second boss 312 protruding from the outer periphery of the negative electrode post body 311; the first boss 212 of one battery cell 10 and the second boss 312 of another battery cell 10 are welded; and an anti-error structure is provided between the first boss 212 of one battery cell 10 and the second boss 312 of another battery cell 10.

[0045] Specifically, the positive electrode post 21 and the negative electrode post 31 are butt-welded. A first boss 212 is provided on the outer periphery of the positive electrode post body 211, and a second boss 312 is provided on the outer periphery of the negative electrode post body 311. After the anti-mistake protrusion 41 is inserted into the anti-mistake groove 42, the first boss 212 and the second boss 312 are butt-welded, facilitating welding.

[0046] In some embodiments, a heat sink 6 is provided in a first groove formed between the first boss 212 and the positive electrode body 211 ; and / or a heat sink 6 is provided in a second groove formed between the second boss 312 and the negative electrode body 311 .

[0047] The first boss 212 is higher than the positive electrode body 211. Therefore, a first groove is formed between the first boss 212 and the positive electrode body 211. A heat sink 6 is arranged in the first groove. When thermal runaway occurs in a battery cell, the heat sink 6 absorbs heat and melts, taking away part of the heat, thereby reducing the probability of thermal runaway in adjacent battery cells.

[0048] In some embodiments, the melting point of the heat sink 6 is not less than 60°C.

[0049] Specifically, the melting point of heat sink 6 is no less than 60°C. When the temperature of a cell exceeds 60°C, heat sink 6 melts, dissipating some of the heat and reducing the probability of thermal runaway in adjacent cells. Heat sink 6 can be made of a low-melting-point material such as PE or PP.

[0050] Preferably, the melting point of the heat absorbing element 6 is between 100°C and 200°C.

[0051] In some embodiments, a plurality of overflow holes 7 are provided on the sidewalls of the first boss 212 and / or the second boss 312 . The overflow holes 7 are suitable for allowing the melted heat absorbing element 6 to flow out.

[0052] By providing the overflow hole 7 , after the heat absorbing element 6 absorbs heat and melts, the heat can flow out from the overflow hole 7 , further taking away the heat and reducing the probability of thermal runaway of adjacent battery cells.

[0053] In some embodiments, at least one thermal insulation sheet 8 is further included. The thermal insulation sheet 8 is provided with a through hole to avoid the positive electrode column 21 or the negative electrode column 31. The thermal insulation sheet 8 is provided on the outer surface of the positive cover plate 2 and / or the negative cover plate 3.

[0054] By providing a thermal insulation sheet 8, the through hole of the thermal insulation sheet 8 is sleeved outside the positive electrode column 21 or the negative electrode column 31. After two adjacent battery cells are connected in series, there is at least one thermal insulation sheet 8 between the positive cover plate 2 and the negative cover plate 3 of the two battery cells. The thermal insulation sheet 8 can play a role in heat insulation. When a battery cell has thermal runaway, it can block part of the heat from being transferred to the adjacent battery cell on the opposite side, thereby reducing the probability of thermal runaway of the adjacent battery cell.

[0055] In some embodiments, the thermal insulation sheet 8 includes aerogel and / or double-sided tape.

[0056] Aerogel or double-sided tape can both provide good thermal insulation.

[0057] In some embodiments, the housing 1 is a structure consisting of four surfaces, and the number of explosion-proof valve 5 is at least one.

[0058] According to an embodiment of the present invention, on the other hand, a battery pack 1000 is also provided, including multiple battery cell units 100, each battery cell unit 100 including multiple battery cells 10 of any one of the above embodiments, two adjacent battery cells 10 in each battery cell unit 100, the positive electrode column 21 of one battery cell 10 and the negative electrode column 31 of another battery cell 10 are conductively abutted, and the two ends of the battery cell unit 100 are respectively the positive electrode column 21 and the negative electrode column 31; the positive electrode column 21 of one battery cell unit 100 and the negative electrode column 31 of another adjacent battery cell unit 100 are conductively connected through a bus 20.

[0059] Specifically, two adjacent battery cells 100, the busbar 20 and the positive electrode 21 of one battery cell 100 are welded to form a weld mark 30, and at the same time, the busbar 20 and the negative electrode 31 of another battery cell 100 are welded to form a weld mark 30, as shown in FIG. Figure 11 shown.

[0060] Specifically, if Figure 12 As shown, the battery pack 1000 includes an upper case 200 and a lower case 300 , and a plurality of battery cell units 100 are arranged between the upper case 200 and the lower case 300 .

[0061] Since the battery pack 1000 includes the battery cell 10 and has the same effects as the battery cell 10 , details thereof will not be repeated here.

[0062] Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations shall fall within the scope defined by the appended claims.

Claims

1. A battery cell, characterized in that: include: A housing having two open ends opposite to each other, and a side wall of the housing being provided with at least one explosion-proof valve; A positive electrode cover plate, the positive electrode cover plate being arranged at one of the open ends of the shell; the positive electrode cover plate being provided with a protruding positive electrode column; A negative electrode cover plate, the negative electrode cover plate being arranged at the other open end of the shell; the negative electrode cover plate being provided with a protruding negative electrode post; The positive electrode post of one of the battery cells is suitable for conductively abutting against the negative electrode post of another of the battery cells.

2. The battery cell according to claim 1, characterized in that The positive electrode cover plate of one battery cell and the negative electrode cover plate of another battery cell are provided with an error-proofing structure.

3. The battery cell according to claim 2, characterized in that The anti-error structure includes an anti-error protrusion and an anti-error groove that are suitable for plugging into each other. The anti-error protrusion is provided on one of the positive pole and the negative pole, and the anti-error groove is provided on the other of the positive pole and the negative pole.

4. The battery cell according to claim 3, characterized in that The positive electrode post comprises a positive electrode post body and a first boss protruding from the outer periphery of the positive electrode post body; The negative electrode post comprises a negative electrode post body and a second boss protruding from the outer periphery of the negative electrode post body; The first boss of one of the battery cells is suitable for being welded to the second boss of another of the battery cells; and the error-proofing structure is provided between the first boss of one of the battery cells and the second boss of another of the battery cells.

5. The battery cell according to claim 4, characterized in that: A heat absorbing member is provided in a first groove formed between the first boss and the positive electrode column body; And / or, a heat absorbing member is provided in a second groove formed between the second boss and the negative electrode body.

6. The battery cell according to claim 5, characterized in that The melting point of the heat absorbing element is not less than 60°C.

7. The battery cell according to claim 6, characterized in that The side walls of the first boss and / or the second boss are provided with a plurality of overflow holes, and the overflow holes are suitable for allowing the melted heat absorbing element to flow out.

8. The battery cell according to any one of claims 1 to 7, characterized in that: It also includes at least one heat insulation sheet, which is provided with a through hole to avoid the positive electrode column or the negative electrode column, and the heat insulation sheet is provided on the outer surface of the positive electrode cover plate and / or the negative electrode cover plate.

9. The battery cell according to claim 8, characterized in that: The thermal insulation sheet includes aerogel and / or double-sided tape.

10. A battery pack, characterized in that: It comprises a plurality of battery cell units, wherein the battery cell units comprise a plurality of battery cells as described in any one of claims 1 to 9, wherein the positive pole of one battery cell and the negative pole of another battery cell of two adjacent battery cells in each battery cell unit are conductively abutted, and the two ends of the battery cell unit are respectively a positive pole and a negative pole; the positive pole of one battery cell unit and the negative pole of another adjacent battery cell unit are conductively connected via a bus.

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