Battery cell monomer and battery system

Abstract

The utility model discloses a battery cell monomer which comprises a square shell main body, a first side plate, a second side plate, a positive electrode assembly, a negative electrode assembly and an explosion venting structure, the first side plate is arranged on the square shell main body; the second side plate is arranged on the square shell main body; the positive electrode assembly is arranged on the first side plate; the negative electrode assembly is arranged on the first side plate; the explosion venting structure is arranged on the second side plate; the first side plate and the second side plate are oppositely arranged. In the battery cell monomers, a first side plate and a second side plate which are oppositely arranged are arranged on a square shell main body, and a positive electrode assembly and a negative electrode assembly are integrated on the first side plate, so that connecting wires and electric parts connected with the battery cell monomers are conveniently arranged on the first side plate arranged in the battery cell monomers; and the second side plate is integrated with an explosion venting structure, so that electrolyte sprayed out of the explosion venting structure due to thermal runaway of the battery cell monomers is far away from a connecting wire and an electric device connected with the positive electrode assembly and the negative electrode assembly, and the safety of the connecting wire and the electric device is improved. The utility model also discloses a battery system.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and more specifically, to a battery cell and a battery system using the battery cell. Background Art

[0002] The battery system is assembled from multiple battery cells. The battery cell includes a square shell body with two ends open and a core pack installed in the square shell body. The ends of the square shell body are provided with both electrodes and explosion-proof valves.

[0003] When thermal runaway of a battery cell causes the explosion-proof valve to open, electrolyte will spray out from the explosion-proof valve, endangering the safety of the battery cell's wiring and electrical components connected to the battery cell through the wiring.

[0004] In summary, how to improve the safety of wiring and electrical components connected to battery cells is an urgent problem to be solved by those skilled in the art. Utility Model Content

[0005] In view of this, the utility model provides a battery cell, whose square shell body is provided with a first side plate and a second side plate arranged oppositely, and the first side plate is integrated with a positive electrode assembly and a negative electrode assembly, so that the positive and negative electrode assemblies of the battery cell are located on the same side, which is convenient for the wiring and electrical components connected to the battery cell to be arranged on the side of the battery cell where the first side plate is provided, and the second side plate is integrated with an explosion relief structure to ensure that the electrolyte sprayed out of the explosion relief structure due to thermal runaway of the battery cell is away from the wiring and electrical components connected to the positive and negative electrode assemblies, thereby improving the safety of the wiring and electrical components. The utility model also provides a battery system using the battery cell as described above, which is conducive to protecting the wiring and electrical components connected to the battery system from the harm of the electrolyte sprayed out by the explosion relief structure when the battery cell is in thermal runaway.

[0006] In order to achieve the above-mentioned purpose, the utility model provides the following technical solutions:

[0007] A battery cell monomer, comprising:

[0008] Square housing body;

[0009] A first side plate, arranged on the square shell body;

[0010] A second side plate, arranged on the square shell body;

[0011] A positive electrode assembly, disposed on the first side plate;

[0012] a negative electrode assembly, disposed on the first side plate; and

[0013] An explosion relief structure, arranged on the second side plate;

[0014] Wherein, the first side plate and the second side plate are arranged opposite to each other.

[0015] Optionally, in the battery cell as described above, the square shell body is a rectangular parallelepiped structure with a length, a height, and a width of L, H, and W, respectively, wherein L>H, and L>W.

[0016] Optionally, in the battery cell as described above, the side lengths of the side of the square shell body on which the first side plate is provided are H and W respectively, and the side lengths of the side of the square shell body on which the second side plate is provided are H and W respectively.

[0017] Optionally, in the battery cell as described above, the width W of the square shell body is greater than the height H of the square shell body.

[0018] Optionally, the battery cell as described above further comprises:

[0019] The liquid injection hole is arranged on the first side plate.

[0020] Optionally, in the battery cell as described above, the first end of the square shell body is open; and the first side plate is fixedly connected to the square shell body and blocks the opening at the first end.

[0021] Optionally, in the battery cell as described above, a first seal is fixed to a surface of the first side plate facing the interior of the square housing body, and the first seal is inserted into the opening at the first end; the first seal is a plastic seal.

[0022] Optionally, in the battery cell as described above, the second end of the square shell body is open; and the second side plate is fixedly connected to the square shell body and blocks the opening at the second end.

[0023] Optionally, in the battery cell as described above, a second seal is fixed to the surface of the second side plate facing the interior of the square housing body, and the second seal is used to be inserted into the opening at the second end; the second seal is a plastic seal.

[0024] A battery system comprises a plurality of battery cells as described in any one of the technical solutions above.

[0025] The utility model provides a battery cell monomer, comprising a square shell body, a first side plate, a second side plate, a positive electrode assembly, a negative electrode assembly, and an explosion relief structure; the first side plate is arranged on the square shell body; the second side plate is arranged on the square shell body; the positive electrode assembly is arranged on the first side plate; the negative electrode assembly is arranged on the first side plate; the explosion relief structure is arranged on the second side plate; wherein the first side plate and the second side plate are arranged opposite to each other.

[0026] In the battery cell as described above, a first side plate and a second side plate arranged opposite to each other are provided on the square shell body, and the first side plate is integrated with a positive electrode assembly and a negative electrode assembly, that is, the positive and negative electrode assemblies of the battery cell are located on the same side of the square shell body, so that the wiring and electrical components connected to the battery cell through the positive and negative electrode assemblies are arranged on the side of the battery cell where the first side plate is provided; at the same time, the second side plate is integrated with an explosion relief structure, so that the explosion relief structure is away from the wiring and electrical components connected to the positive and negative electrode assemblies, which is beneficial to ensure that when the explosion relief structure explodes due to thermal runaway of the battery cell, the sprayed electrolyte is away from the wiring and electrical components connected to the positive and negative electrode assemblies, thereby improving the safety of the wiring and electrical components.

[0027] The utility model also provides a battery system using the battery cell monomer as described above, which is beneficial to protect the wiring and electrical components connected to the battery system from the harm of the electrolyte sprayed by the explosion relief structure when the battery cell monomer thermally runs away. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 An exploded view of a battery cell provided in an embodiment of the utility model;

[0030] Figure 2 A schematic diagram of the assembly of the first side plate, the positive electrode assembly, and the negative electrode assembly provided in an embodiment of the utility model;

[0031] Figure 3 A schematic diagram of the assembly of the second side plate and the explosion relief structure provided in an embodiment of the utility model;

[0032] Figure 4 A schematic diagram of the structure of a battery cell in a core package provided by an embodiment of the utility model;

[0033] Figure 5 A schematic diagram of the three-dimensional structure of a battery cell provided in an embodiment of the utility model;

[0034] in, Figure 1-Figure 5 middle:

[0035] The second side plate 101 ; the core package 102 ; the positive electrode ear 121 ; the negative electrode ear 122 ; the second connecting piece 103 ; the first side plate 104 ; the first connecting piece 105 ; the square shell body 106 ; the positive electrode assembly 107 ; the injection hole 108 ; the negative electrode assembly 109 ; the first sealing member 110 ; and the explosion relief structure 111 . DETAILED DESCRIPTION

[0036] The utility model embodiment discloses a battery cell, whose square shell body is provided with a first side plate and a second side plate arranged oppositely, and the first side plate is integrated with a positive electrode assembly and a negative electrode assembly, so that the positive and negative electrode assemblies of the battery cell are located on the same side, which is convenient for the wiring and electrical components connected to the battery cell to be arranged on the side of the battery cell where the first side plate is provided, and the second side plate is integrated with an explosion relief structure, so as to ensure that the electrolyte sprayed out of the explosion relief structure due to thermal runaway of the battery cell is away from the wiring and electrical components connected to the positive and negative electrode assemblies, thereby improving the safety of the wiring and electrical components. The utility model embodiment also discloses a battery system using the battery cell as described above, which is beneficial for protecting the wiring and electrical components connected to the battery system from the harm of the electrolyte sprayed out by the explosion relief structure when the battery cell is in thermal runaway.

[0037] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0038] See also Figure 1-Figure 5 The embodiment of the utility model provides a battery cell, including a square shell body 106, a first side plate 104, a second side plate 101, a positive electrode assembly 107, a negative electrode assembly 109, and an explosion-proof structure 111; the first side plate 104 is arranged on the square shell body 106; the second side plate 101 is arranged on the square shell body 106; the positive electrode assembly 107 is arranged on the first side plate 104; the negative electrode assembly 109 is arranged on the first side plate 104; the explosion-proof structure 111 is arranged on the second side plate 101; wherein the first side plate 104 and the second side plate 101 are arranged opposite to each other, so that the explosion-proof structure 111 does not affect the structural integrity of the positive and negative electrode assemblies when venting the explosion, and also avoids the electrolyte from spraying onto the positive and negative electrode assemblies.

[0039] It should be noted that the first side plate 104 and the second side plate 101 are arranged on the side surfaces of the square housing body 106, rather than on the top surface or bottom surface of the square housing body 106. The top surface and bottom surface refer to the top surface and bottom surface of the square housing body 106 when the battery cell is in normal use.

[0040] In the embodiment of the utility model, the first side plate 104 and the second side plate 101 can be fixed to the opening of the square shell body 106 by welding. The square shell body 106 can be set as an aluminum shell. The first side plate 104 and the second side plate 101 can also be set as an integrated structure with the square shell body 106; during production, the square shell body 106, the first side plate 104 and the second side plate 101 are integrally formed outside the core package 102.

[0041] In the battery cell as described above, a first side plate 104 and a second side plate 101 arranged opposite to each other are provided on the square shell body 106, and the first side plate 104 is integrated with a positive electrode assembly 107 and a negative electrode assembly 109, that is, the positive and negative electrode assemblies 109 of the battery cell are located on the same side of the square shell body 106, so that the wiring and electrical components connected to the battery cell through the positive and negative electrode assemblies 109 are arranged on the side of the battery cell where the first side plate 104 is provided; at the same time, the second side plate 101 is integrated with an explosion relief structure 111, so that the explosion relief structure 111 is kept away from the wiring and electrical components connected to the positive and negative electrode assemblies 109, which is beneficial to ensure that when the explosion relief structure 111 explodes due to thermal runaway of the battery cell, the sprayed electrolyte is kept away from the wiring and electrical components connected to the positive and negative electrode assemblies 109, thereby improving the safety of the wiring and electrical components.

[0042] The square housing body 106 is set as a rectangular parallelepiped structure, including three dimensions of length L, height H and width W. Accordingly, the cross section of the square housing body 106 is a rectangle. The length dimension L of the battery cell>the height dimension H of the battery cell, and the length dimension L of the battery cell>the width dimension W of the battery cell.

[0043] The side lengths of the side of the square housing body 106 on which the first side plate 104 is disposed are H and W respectively, and the side lengths of the side of the square housing body 106 on which the second side plate 101 is disposed are H and W respectively.

[0044] In one embodiment, the length dimension L of the square housing body 106>the width dimension W of the square housing body 106>the height dimension H of the square housing body 106. The length dimension L is 300 mm to 2000 mm, the width dimension W is 30 mm to 300 mm, and the height dimension H is 30 mm to 100 mm; the ratio of the width dimension W to the length dimension L is in the range of: ≤1 / 2.

[0045] In normal use, the square housing body 106 can be arranged with its length direction arranged in a horizontal direction or a nearly horizontal direction. The first side plate 104 and the second side plate 101 are respectively located at two ends of the square housing body 106 in the length direction.

[0046] The battery cell monomer has a flat structure, and a plurality of battery cell monomers are used in combination, and each battery cell monomer can be stacked one by one in the vertical direction.

[0047] The positive electrode assembly 107 and the negative electrode assembly 109 are distributed at opposite ends of the first side plate 104. This arrangement leaves more space between the positive electrode assembly 107 and the negative electrode assembly 109, making it convenient for users to perform wiring operations on the positive electrode assembly 107 and the negative electrode assembly 109 respectively.

[0048] An electrode mark is provided on the outer side surface of the first side plate 104 near the positive electrode assembly 107 and / or the negative electrode assembly 109, so that the user can distinguish the positive electrode assembly 107 from the negative electrode assembly 109. In one embodiment, a positive electrode mark "+" is provided on the outer side surface of the first side plate 104 near the positive electrode assembly 107, and a negative electrode mark "-" is provided on the outer side surface of the first side plate 104 near the negative electrode assembly 109.

[0049] The battery cell as described above further includes a liquid injection hole 108, which is provided on the first side plate 104 and communicates with the interior of the square housing body 106, for injecting electrolyte into the interior of the square housing body 106 during production. The first side plate 104 can be provided as a plain aluminum plate.

[0050] In one embodiment, the first end of the square housing body 106 is open; the first side plate 104 is fixedly connected to the square housing body 106 and blocks the opening at the first end of the square housing body 106. A first sealing member 110 is fixed on the surface of the first side plate 104 facing the inside of the square housing body 106, and the first sealing member 110 is inserted into the opening at the first end of the square housing body 106 and seals the gap between the first side plate 104 and the square housing body 106. The first sealing member 110 can be set as a plastic sealing member.

[0051] The first seal 110 can be integrally injection molded with the first side plate 104 , or the first seal 110 can be fixed to the first side plate 104 by bonding, connecting with a fixing member, etc. This embodiment does not limit the connection method between the first seal 110 and the first side plate 104 .

[0052] In another embodiment, the second end of the square housing body 106 is open; the second side plate 101 is fixedly connected to the square housing body 106 and blocks the opening at the second end of the square housing body 106. A second sealing member is fixed on the surface of the second side plate 101 facing the inside of the square housing body 106, and the second sealing member is used to be inserted into the opening at the second end of the square housing body 106 and seal the gap between the second side plate 101 and the square housing body 106. The second sealing member can be set as a plastic sealing member.

[0053] The second sealing member may be integrally formed by injection molding with the second side plate 101 , or the second sealing member may be fixed to the second side plate 101 by bonding, connecting with a fixing member, or the like. The present embodiment does not limit the connection method between the second sealing member and the second side plate 101 .

[0054] In one embodiment, the openings at the first end and the second end of the square housing body 106 face opposite directions to ensure that the electrolyte sprayed from the explosion relief structure 111 faces away from the positive electrode assembly 107 and the negative electrode assembly 109 during thermal runaway, thereby maximizing the protection of the wiring and electrical components connected to the positive electrode assembly 107 and the negative electrode assembly 109.

[0055] In some embodiments, the battery cell also includes an electrolyte recovery device, which is connected to the explosion relief structure 111; when the explosion relief structure 111 is vented, the electrolyte carries heat away from the battery cell and is recovered by the electrolyte recovery device, so that the battery cell is thermally and electrically separated, which can effectively improve the safety of the battery system using the battery cell.

[0056] The explosion relief structure 111 may be configured as an explosion-proof valve installed on the second side plate 101; and the second side plate 101 may be configured as a plain aluminum sheet.

[0057] The positive electrode assembly 107 includes a positive electrode column fixed to the first side plate 104 ; the negative electrode assembly 109 includes a negative electrode column fixed to the first side plate 104 .

[0058] The square housing body 106 is a cylindrical structure with two ends open, and a core pack 102 is arranged inside. The core pack 102 leads out a positive electrode tab 121 and a negative electrode tab 122 on the same side; the positive electrode assembly 107 is electrically connected to the positive electrode tab 121, and the negative electrode assembly 109 is electrically connected to the negative electrode tab 122.

[0059] In the battery cell provided in the present embodiment, both the positive electrode ear 121 and the negative electrode ear 122 are led out from the same side of the core package 102, and it is only necessary to reserve space on the same side inside the core package 102 to satisfy the bending space required when the positive electrode ear 121 and the negative electrode ear 122 are connected to the corresponding poles. In other words, the positive electrode ear 121 and the negative electrode ear 122 of the core package 102 are bent and deformed in the same space, avoiding the need to reserve space at both ends of the core package 102 to respectively satisfy the bending requirements of the positive electrode ear 121 and the negative electrode ear 122, so that the size of the core package 102 along the direction from the first end to the second end of the square shell body 106 can be set to be larger, thereby improving the capacity of the battery cell.

[0060] In addition, in the battery cell provided in this embodiment, the positive electrode assembly 107 and the negative electrode assembly 109 are arranged on the same side of the battery cell, so that the exposed height dimension of the electrode assembly on one side of the entire battery cell is omitted, the occupied space is smaller, and it is beneficial to improve the energy density of the battery system using the battery cell.

[0061] The positive electrode ear 121 can be configured to be welded to the positive electrode assembly 107 through the first connecting sheet 105, or the positive electrode ear 121 can be configured to be directly welded to the positive electrode assembly 107; the negative electrode ear 122 can be configured to be welded to the negative electrode assembly 109 through the second connecting sheet 103, or the negative electrode ear 122 can be configured to be directly welded to the negative electrode assembly 109.

[0062] In this embodiment, the positive electrode ear 121 and the positive electrode assembly 107, the negative electrode ear 122 and the negative electrode assembly 109 can be directly welded, or welded through a connecting piece, so that the user can flexibly choose the connection method between the positive and negative electrode ears and the corresponding positive and negative electrode assemblies 109, and ensure that the positive and negative electrode ears are reliably electrically connected to the corresponding positive and negative electrode assemblies 109.

[0063] In the battery cell monomer described above, the core pack 102 can be provided as one. The core pack 102 can also be provided as a plurality, and each core pack 102 is stacked; the positive pole ears 121 of all the core packs 102 are welded to the positive electrode assembly 107 by the same first connecting sheet 105, and the negative pole ears 122 of all the core packs 102 are welded to the negative electrode assembly 109 by the same second connecting sheet 103, so as to save parts, simplify the connection structure between the pole ears of the core pack 102 and the corresponding electrode assembly, reduce the space occupied by the connection structure between the pole ears and the corresponding electrode assembly, and maximize the capacity of the battery cell monomer.

[0064] The core pack 102 can be a soft core pack, a wound battery core pack or a laminated core pack. The soft core pack is a battery core pack that uses a multi-layer flexible composite polymer film as an outer shell. This battery core pack is similar to a traditional liquid lithium-ion battery, but the outer layer is covered with a polymer shell and is usually packaged with an aluminum-plastic film. The battery cell of the wound battery core pack is formed by a winding combination, and has the advantages of simple production process, high production efficiency, and high utilization rate of negative electrode active materials. The battery cell of the laminated core pack is formed by a lamination process, and its appearance will be flatter, with higher space utilization and the advantage of high energy density.

[0065] In the prior art, the assembly process of the battery cell is complicated. The battery cell includes a square shell body, a core pack arranged in the square shell body, and a positive electrode top cover assembly and a negative electrode top cover assembly arranged at both ends of the square shell body. During assembly, the core pack must first be welded to the first connecting piece and the second connecting piece respectively; then the second connecting piece must be welded to the negative electrode top cover assembly in the battery cell; the core pack must be insulated, and then the core pack must be placed in the square shell body; the negative electrode top cover assembly must be welded to the square shell body; the first connecting piece must be welded to the positive electrode top cover assembly; and finally, the positive electrode top cover assembly must be welded to the square shell body.

[0066] After adopting the battery cell provided by the utility model, the assembly process is greatly simplified: first, the first side plate 104 and the square shell body 106 are welded in advance at the raw material stage; the core package 102 is welded to the first connecting piece 105 and the second connecting piece respectively; the first connecting piece 105 and the second connecting piece are welded to the positive pole of the positive electrode assembly 107 and the negative pole of the negative electrode assembly 109 respectively; the core package 102 is insulated; the core package 102 is installed in the square shell body 106; the first side plate 104 and the square shell body 106 are welded.

[0067] The embodiment of the utility model further provides a battery system, which includes a plurality of battery cells as described above, and the plurality of battery cells are connected in series, in parallel or in a combination of series and parallel.

[0068] In the embodiment of the utility model, the battery system can be a battery module, or a battery pack composed of several battery cells as described above, or a battery cluster composed of several battery cells as described above, which is not specifically limited here.

[0069] It should be noted that "a battery pack composed of several battery cells as described above" means that the battery pack is no longer composed of several battery modules, but is directly composed of several battery cells and other necessary structures. The battery pack omits the traditional process of assembling battery cells into battery modules, and is directly assembled into a battery pack from battery cells and other necessary structures, effectively improving space utilization.

[0070] Similarly, "a battery cluster composed of several battery cells as described above" means that the battery cluster is no longer composed of several battery packs, but is directly composed of several battery cells and other necessary structures. The battery cluster omits the two steps of assembling traditional battery cells into battery modules and assembling battery modules into battery packs, and directly assembles battery cells and other necessary structures into battery packs, effectively improving space utilization.

[0071] The battery system provided in this embodiment uses the battery cell provided in the above embodiment, which is beneficial to protect the wiring and electrical components connected to the battery system from the harm of the electrolyte sprayed by the explosion relief structure 111 when the battery cell is thermally runaway. Of course, the battery system provided in this embodiment also has other effects related to the battery cell provided in the above embodiment, which will not be repeated here.

[0072] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0073] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A battery cell monomer, characterized in that: include: Square housing body; A first side plate, arranged on the square shell body; A second side plate, arranged on the square shell body; A positive electrode assembly, disposed on the first side plate; A negative electrode assembly, disposed on the first side plate; as well as An explosion relief structure, arranged on the second side plate; Wherein, the first side plate and the second side plate are arranged opposite to each other.

2. The battery cell according to claim 1, characterized in that: The square shell body is a rectangular parallelepiped structure with a length, a height, and a width of L, H, and W, respectively, wherein L>H, and L>W.

3. The battery cell according to claim 2, characterized in that: The side lengths of the side of the square shell body on which the first side plate is arranged are H and W respectively, and the side lengths of the side of the square shell body on which the second side plate is arranged are H and W respectively.

4. The battery cell according to claim 2, characterized in that: The width W of the square shell body is greater than the height H of the square shell body.

5. The battery cell according to claim 1, characterized in that: Also includes: The liquid injection hole is arranged on the first side plate.

6. The battery cell according to claim 1, characterized in that: The first end of the square shell body is open; the first side plate is fixedly connected to the square shell body and blocks the opening at the first end.

7. The battery cell according to claim 6, characterized in that: A first sealing member is fixed to a surface of the first side plate facing the interior of the square housing body, and the first sealing member is inserted into the opening at the first end; the first sealing member is a plastic sealing member.

8. The battery cell according to claim 1, characterized in that: The second end of the square shell body is open; the second side plate is fixedly connected to the square shell body and blocks the opening at the second end.

9. The battery cell according to claim 8, characterized in that: A second sealing member is fixed on a surface of the second side plate facing the interior of the square housing body, and the second sealing member is used to be inserted into the opening at the second end; the second sealing member is a plastic sealing member.

10. A battery system, characterized in that: The invention comprises a plurality of battery cell monomers as claimed in any one of claims 1 to 9.

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