Battery cell structure and battery module

Abstract

The utility model discloses a battery cell structure and a battery module, and relates to the technical field of batteries. The battery cell structure comprises a pole group assembly and a cover plate assembly, wherein the pole group assembly comprises a pole group body and two tab structures; the cover plate assembly comprises an insulating part, an end cover and two pole columns, the insulating part comprises a first insulating part and a second insulating part which are connected, the first insulating part and the second insulating part are located on the two opposite sides of the end cover respectively, and the pole columns are arranged on the side, away from the pole group body, of the end cover; the first insulation part is located between the pole columns and the end cover, the second insulation part is located between the pole group body and the end cover, and the two pole lug structures penetrate through the insulation parts and the end cover, correspond to the two pole columns one by one and are electrically connected with the two pole columns. The battery cell structure improves the utilization rate of the internal space, so that the energy density is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery technology field especially relates to a kind of battery cell structure and battery module. BACKGROUND

[0002] With the rapid development of new energy battery technology, the popularity rate of new energy vehicles in the market is also gradually increasing, and the focus of people's attention is mainly concentrated on the cruising range of new energy vehicles. In view of the above problems, for power battery production enterprises, how to improve the energy density of battery has become a technical problem that needs to be continuously overcome.

[0003] In the prior art, the pole post of the battery cell structure passes through the cover plate assembly and is electrically connected with the corresponding tab structure through the busbar, so that the battery cell structure can supply power externally. However, the busbar and the pole post will occupy the internal space of the battery cell structure, thereby affecting the effective volume of the pole group assembly and reducing the energy density of the battery cell structure. SUMMARY

[0004] The utility model aims at providing a kind of battery cell structure and battery module, improve internal space utilization, thereby improve energy density.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] A kind of battery cell structure, comprising:

[0007] A pole group assembly, the pole group assembly includes a pole group body and two tab structures;

[0008] A cover plate assembly, the cover plate assembly includes an insulating part, an end cover and two pole posts, the insulating part includes a first insulating part and a second insulating part connected, the first insulating part and the second insulating part are located on opposite sides of the end cover respectively, the pole post is arranged on the side of the end cover away from the pole group body, the first insulating part is located between the pole post and the end cover, the second insulating part is located between the pole group body and the end cover, two tab structures are arranged in the insulating part and the end cover and are one-to-one corresponding and electrically connected with two pole posts.

[0009] As an optional solution of the above battery cell structure, the cover plate assembly further includes a shaping plastic part, the shaping plastic part is connected with the second insulating part, the tab structure includes a connecting part and a transition part, the size of the transition part in the thickness direction of the pole group assembly gradually decreases along the direction close to the connecting part, the shaping plastic part is provided with a shaping part on the side facing the pole group assembly, the shaping part is provided with a through hole, the connecting parts of two tab structures are arranged in the corresponding through holes of the shaping plastic part respectively, and the shaping part is configured to abut against the corresponding transition part to shape the transition part.

[0010] As an optional solution for the above-mentioned battery cell structure, the shaping portion includes two shaping surfaces that are spaced apart and arranged at an angle, the through hole is located between the two shaping surfaces, the distance between the two shaping surfaces gradually decreases in the direction approaching the through hole, and the shaping surface is configured to press against the surface of the transition portion on one side of the connecting portion.

[0011] As an optional solution to the above-mentioned battery core structure, the shaped plastic part is provided with a snap-fit ​​groove, and the second insulating part is arranged in the snap-fit ​​groove and has an interference fit with the snap-fit ​​groove.

[0012] As an optional solution to the above-mentioned battery cell structure, the battery cell structure also includes a shell and a side plate, the shell includes an opening and a bottom plate arranged opposite to each other, the cover plate assembly is connected to the shell to seal the opening, and the side plate is arranged in the shell and located between the pole group assembly and the bottom plate.

[0013] As an optional solution to the above-mentioned battery cell structure, the cover plate assembly also includes a connecting piece, the first insulating part is provided with a connecting groove, the connecting piece is arranged in the connecting groove, and the pole ear structure passes through the insulating part and is bent and electrically connected to the pole through the connecting piece.

[0014] As an optional solution to the above-mentioned battery cell structure, the cover plate assembly further includes a fixing ring, and the fixing ring is configured to fix the pole on the end cover.

[0015] As an optional solution to the above-mentioned battery cell structure, the fixing ring includes a fixing section, a transition section and a pressing section, a flange is protruded from the outer periphery of the pole, the fixing section is fixedly connected to the end cover, and the flange is arranged between the pressing section and the end cover.

[0016] As an optional solution to the above-mentioned battery core structure, the fixing ring sleeve is provided with an insulating ring, and the insulating ring covers the transition section, the pressing section and part of the fixing section.

[0017] A battery module comprises a plurality of the battery core structures described above, wherein the plurality of the battery core structures are connected in series or in parallel.

[0018] Beneficial effects of the utility model:

[0019] The utility model provides a battery cell structure and a battery module. In the battery cell structure, an insulating portion is used to separate the pole, end cap, and pole group body to prevent short circuits. The pole tab structure passes through the insulating portion and end cap and is led out to the side of the end cap facing away from the pole group body, where it is electrically connected to the pole. This allows the pole to be located externally and eliminates the need for a busbar structure, thereby freeing up space for the pole group assembly, improving internal space utilization, and thereby increasing energy density. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is an exploded view of the battery cell structure provided by the present utility model;

[0021] Figure 2 This is a top view of the battery core structure provided by the utility model;

[0022] Figure 3 yes Figure 2 Cross-sectional view at AA in the middle;

[0023] Figure 4 yes Figure 3 A partial enlarged view of point B in the middle;

[0024] Figure 5 This is a first structural diagram of the insulating portion and the plastic part provided by the utility model;

[0025] Figure 6 This is a second structural diagram of the insulating portion and the plastic part provided by the utility model;

[0026] Figure 7 It is a structural schematic diagram of the electrode group component provided by the utility model.

[0027] In the picture:

[0028] 1. Shell; 11. Opening; 12. Explosion-proof valve; 13. Liquid injection hole;

[0029] 2. Pole group assembly; 21. Pole group body; 22. Pole ear structure; 221. Connecting portion; 222. Transition portion;

[0030] 3. Cover plate assembly; 31. Insulation portion; 311. First insulation portion; 312. Second insulation portion; 313. Connection groove; 32. End cap; 33. Pole; 34. Connecting piece; 35. Fixing ring; 351. Fixing section; 352. Transition section; 353. Pressing section; 36. Insulation ring; 37. Sealing ring; 38. Plastic part; 381. Through hole; 382. Plastic surface;

[0031] 4. Protective film;

[0032] 5. Side panels. DETAILED DESCRIPTION

[0033] The following describes in detail embodiments of the present invention. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, and should not be construed as limiting the present invention.

[0034] In the description of the utility model, it is necessary to explain that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the utility model and simplifying the description, and do not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the utility model. In addition, the terms "first" and "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions.

[0035] Unless otherwise expressly specified and limited, the terms "mounting", "connection", "connection", "fixing" should be understood broadly, for example, it can be fixed connection, but also can be detachable connection; can be mechanical connection, but also can be electrical connection; can be directly connected, but also indirectly connected through an intermediate medium, can be the internal communication of two elements or the interaction relationship of two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0036] Unless otherwise expressly specified and limited, the first feature "on" or "under" the second feature can include that the first feature and the second feature are in direct contact, or the first feature and the second feature are not in direct contact but are in contact through another feature between them. Moreover, the first feature "on", "above" and "above" the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "under", "below" and "below" the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0037] The technical scheme of the utility model will be further illustrated below in combination with the drawings and through specific embodiments.

[0038] With the rapid development of new energy battery technology, the popularization rate of new energy vehicles in the market is also gradually increasing, and the focus of people's attention is mainly concentrated on the endurance mileage of new energy vehicles. In view of the above problems, for power battery production enterprises, how to improve the energy density of the battery has become a technical problem that needs to be continuously overcome.

[0039] As the power source for new energy vehicles, the battery pack directly impacts their range and safety. The battery pack consists of a housing and multiple battery cells, which are arranged in series or parallel. To maximize the volume utilization within the housing and thus the energy density of the battery pack, the cells are typically arranged in square or blade configurations. Both configurations offer the advantage of being able to be tightly packed, ensuring the maximum possible number of cells can be accommodated within the battery pack.

[0040] In this embodiment, the cell structure is described using a square shell cell as an example. To facilitate electrical connection, the positive and negative electrode columns of the cell structure are both located on the cover assembly.

[0041] like Figure 1 As shown, in this embodiment, the battery cell structure includes a housing 1, an electrode group assembly 2, and a cover plate assembly 3. The electrode group assembly 2 is disposed within the housing 1. The electrode group assembly 2 includes an electrode group body 21 and two electrode tab structures 22 disposed on the electrode group body 21. The electrode group body 21 includes a plurality of positive electrode sheets and a plurality of negative electrode sheets stacked in layers, and adjacent positive electrode sheets and negative electrode sheets are separated by a diaphragm to prevent short circuits. The housing 1 has an opening 11, which is filled with electrolyte. The cover plate assembly 3 blocks the opening 11 of the housing 1, thereby forming a closed internal space in the housing 1. This can prevent electrolyte overflow and protect the electrode group assembly 2.

[0042] like Figure 1 、 Figures 4 to 6 As shown, the cover plate assembly 3 includes an insulating portion 31, an end cover 32 and two poles 33. The poles 33 are arranged corresponding to the pole ear structure 22. The insulating portion 31 includes a first insulating portion 311 and a second insulating portion 312 connected to each other. The first insulating portion 311 and the second insulating portion 312 are respectively located on opposite sides of the end cover 32. The pole 33 is arranged on the side of the end cover 32 away from the pole group body 21. The first insulating portion 311 is located between the pole 33 and the end cover 32, and the second insulating portion 312 is located between the pole group body 21 and the end cover 32.

[0043] The cover assembly 3 replaces the traditional upper plastic and lower plastic structures with the first insulating part 311 and the second insulating part 312 of the insulating part 31, thereby simplifying the structure. The connected first insulating part 311 and the second insulating part 312 can play a fixing role from both sides of the end cover 32, and also eliminates the structure of fixing the upper plastic and the end cover 32 and the lower plastic and the end cover 32, saving the assembly process, thereby improving efficiency and reducing costs.

[0044] In the prior art, after the poles 33 of the cell structure pass through the cover plate assembly 3, they need to be electrically connected to the corresponding tab structure 22 via a busbar to enable the cell structure to supply power. However, both the busbar and the poles 33 occupy the internal space of the cell structure, thereby reducing the effective volume of the electrode assembly 2 and lowering the energy density of the cell structure.

[0045] like Figure 4 As shown, to solve the above problems, in the battery cell structure provided by this embodiment, two tab structures 22 are provided through the insulating portion 31 and the end cover 32 and correspond one-to-one with the two pole posts 33 and are electrically connected. In this battery cell structure, the insulating portion 31 is used to separate the pole posts 33, the end cover 32, and the pole group body 21 to prevent short circuits, while the tab structures 22 pass through the insulating portion 31 and the end cover 32 and are led out to the side of the end cover 32 facing away from the pole group body 21, and are electrically connected to the pole posts 33. This allows the pole posts 33 to be located externally and eliminates the busbar structure, thereby freeing up space for the pole group assembly 2, improving internal space utilization, and thus increasing energy density.

[0046] In this embodiment, the cover plate assembly 3 is provided with an explosion-proof valve 12 and a liquid injection hole 13. The explosion-proof valve 12 is used to discharge high-temperature, high-pressure gases generated within the housing 1 in the event of thermal runaway of the battery cell structure, preventing the battery cell structure from exploding and causing serious consequences. The liquid injection hole 13 is used to inject electrolyte into the housing 1 after the cover plate assembly 3 is secured to the housing 1, enabling the battery cell structure to function properly.

[0047] In some embodiments, the end cap 32 is provided with a mounting hole, and the explosion-proof valve 12 is disposed in the mounting hole. In some embodiments, in order to reduce costs, the explosion-proof valve 12 can also be formed by engraving lines on the end cap 32. The engraved lines can be on the inside or outside of the end cap 32.

[0048] It is worth noting that if Figure 1 、 Figure 4 and Figure 7 As shown, multiple positive electrode sheets are connected to foils, and the distal ends of the multiple foils are fixed together by ultrasonic welding to form the connection portion 221 of the tab structure 22. The portion of the foils not welded together forms the transition portion 222 of the tab structure 22. Similarly, multiple negative electrode sheets are connected to foils, and the distal ends of the multiple foils are fixed together by ultrasonic welding to form the connection portion 221 of the tab structure 22. The portion of the foils not welded together forms the transition portion 222 of the tab structure 22. Moreover, the dimension of the transition portion 222 in the thickness direction of the electrode assembly 2 gradually decreases as it approaches the connection portion 221.

[0049] However, since the foil material of the transition portion 222 is in a loose and uncontrolled state, it will affect the electrical performance of the battery cell structure and is likely to protrude and touch the housing 1 to cause a short circuit, thereby affecting the safety of the new energy vehicle.

[0050] like Figure 1 、 Figures 3 to 6 As shown, in order to solve the above problems, the cover plate assembly 3 also includes a shaping plastic part 38, which is connected to the second insulating part 312, and the pole ear structure 22 includes a connecting part 221 and a transition part 222. The size of the transition part 222 in the thickness direction of the pole group assembly 2 gradually decreases along the direction close to the connecting part 221. The shaping part 38 is provided with a shaping part on the side facing the pole group assembly 2, and the shaping part is provided with a through hole 381. The connecting parts 221 of the two pole ear structures 22 are respectively passed through the corresponding through holes 381 of the shaping plastic part 38, and the shaping part is configured to abut the corresponding transition part 222 to shape the transition part 222.

[0051] Since the connection portion 221 of the pole ear of the pole group assembly 2 is passed through the through hole 381 of the plastic part, the shaping portion can abut the transition portion 222 to shape the transition portion 222, so that the shape of the transition portion 222 is in a controlled state, avoiding the transition portion 222 from bending or protruding, which may easily touch the shell 1 and cause a short circuit, thereby ensuring the electrical performance of the battery cell structure and improving the safety of new energy vehicles.

[0052] like Figures 4 to 6 As shown, the shaping portion includes two shaping surfaces 382 spaced apart from each other. The shaping surfaces 382 are configured to press against the surface of the transition portion 222 located on one side of the connecting portion 221. The through hole 381 is located between the two shaping surfaces 382. Generally speaking, the transition portion 222 is symmetrical about the connecting portion 221. Therefore, the two shaping surfaces 382 on either side of the through hole 381 can respectively shape the portion of the transition portion 222 located on one side of the connecting portion 221, thereby ensuring the shaping effect of the transition portion 222 and preventing the transition portion 222 from bending or bulging.

[0053] In this embodiment, the two shaping surfaces 382 are arranged at an angle, and the distance between the two shaping surfaces 382 gradually decreases as they approach the through hole 381. The inclination direction of the surface of the transition portion 222 is substantially the same as the inclination direction of the shaping surface 382, ​​so that the shaping surface 382 can shape the transition portion 222 along the direction of the transition portion 222. This allows the transition portion 222 to be shaped while ensuring a small amount of deformation, thereby ensuring a good shaping effect while preventing damage to the transition portion 222 due to excessive deformation.

[0054] It is understood that the relative position between the shaping plastic part 38 and the electrode assembly 2 must be relatively accurate to avoid the connection portion 221 having to be bent to be inserted into the through hole 381, resulting in unequal distances between the two shaping surfaces 382 and the transition portion 222, which would affect the shaping effect. To achieve this purpose, the shaping plastic part 38 is provided with a snap-fit ​​groove, and the second insulating portion 312 is disposed in the snap-fit ​​groove and has an interference fit therewith.

[0055] In this embodiment, to increase the battery cell's electrical capacity, the cell structure includes at least two electrode assembly assemblies 2. The plastic component of each cover assembly 3 is provided with a shaping portion and through-hole 381 corresponding to each electrode assembly 2. Multiple electrode assembly assemblies 2 can increase electrical capacity, and compared to the increased thickness of a single electrode assembly 2, dividing the multiple electrode assembly assemblies 2 into multiple groups can reduce the difficulty of lamination, improve product yield, and reduce costs. The plastic component of the cover assembly 3 can shape the transition portion 222 of the tab structure 22 of the multiple electrode assembly assemblies 2 at the corresponding end, thereby ensuring the electrical performance of the cell structure.

[0056] like Figure 1 and Figure 7 As shown, in this embodiment, the battery cell structure includes two sets of pole group assemblies 2, that is, there are four pole ear structures 22. After the connecting parts 221 of the four pole ear structures 22 pass through the plastic part 38, the insulating part 31 and the end cover 32, the pole ear structures 22 of the same electrical properties of the two sets of pole group assemblies 2 are connected to the same pole 33, that is, the two sets of pole group assemblies 2 are connected in parallel.

[0057] In this embodiment, a protective film 4 is provided on the outside of the electrode assembly 2. The protective film 4 enables the positive electrode sheet and the negative electrode sheet to be stacked more tightly together, protects the electrode sheets, and prevents the electrode sheets from contacting the housing 1 and causing short circuits or leakage. It is worth noting that if the battery cell structure includes multiple electrode assembly assemblies 2, the protective film 4 can be provided on the outside of each electrode assembly 2, or all electrode assembly assemblies 2 can be provided with the protective film 4.

[0058] In this embodiment, the cell structure further includes a side panel 5. The housing 1 has a bottom panel positioned opposite the opening 11. The side panel 5 is positioned within the housing 1 and between the electrode assembly 2 and the housing 1. The side panel 5 separates the electrode assembly 2 from the housing 1, providing support and protection for the electrode assembly 2 while also preventing the electrode assembly from directly contacting the housing 1 and causing deformation, which could affect electrical performance. It is worth noting that the side panel 5 can be positioned between the electrode assembly 2 and the protective film 4, or between the protective film 4 and the housing 1.

[0059] like Figure 1 and Figure 4As shown, the cover plate assembly 3 also includes a connecting piece 34. The first insulating portion 311 defines a connecting groove 313, and the connecting piece 34 is disposed within the connecting groove 313. The tab structure 22 passes through the portion of the insulating portion 31 and is bent, then electrically connected to the pole 33 via the connecting piece 34. After the connecting portion 221 passes through the plastic part 38 and the insulating portion 31, it is bent toward the connecting piece 34 and welded to the connecting piece 34. The pole 33 is then fixed to the end cap 32 to electrically connect the pole 33 and the connecting piece 34. This avoids the problem of the connecting portion 221 being blocked by the pole 33 when directly connecting to the pole 33, making welding difficult. This reduces assembly difficulty and improves product yield.

[0060] It is worth noting that the connecting piece 34 is provided with a protruding connecting post. When the terminal post 33 is arranged on the end cover 32, it can abut against the connecting post, thereby realizing the electrical connection between the end cover 32 and the connecting piece 34. The depth of the connecting groove 313 is less than or equal to the thickness of the connecting piece 34, so that the connecting portion 221 of the tab structure 22 only needs to be bent once to be attached to the connecting piece 34, so as to facilitate welding, which greatly reduces the possibility of the connecting portion 221 breaking or affecting the electrical performance due to multiple bending.

[0061] like Figure 1 and Figure 4 As shown, the cover plate assembly 3 further includes a fixing ring 35, which is configured to fix the pole 33 to the end cover 32. It is understandable that since the pole 33 needs to be insulated from the end cover 32, it is not possible to directly weld the pole 33 to the end cover 32, so the fixing ring 35 is required for indirect fixation.

[0062] Specifically, the fixing ring 35 includes a fixing section 351, a transition section 352, and a press-fit section 353. A flange is provided on the outer periphery of the pole 33. The fixing section 351 is fixedly connected to the end cover 32, and the flange is disposed between the press-fit section 353 and the end cover 32. Because the fixing ring 35 is fixedly connected to the end cover 32 via the fixing section 351, the press-fit section 353 can press the flange of the pole 33 onto the end cover 32, ensuring that the pole 33 does not separate from the end cover 32.

[0063] It is worth noting that to ensure a reliable connection between the fixing ring 35 and the end cap 32, the fixing ring 35 and the end cap 32 are welded together, thus ensuring insulation between the fixing ring 35 and the pole 33. To achieve this, the fixing ring 35 is sleeved with an insulating ring 36, which covers the transition section 352, the press-fit section 353, and a portion of the fixed section 351. The insulating ring 36 covers the transition section 352 and the press-fit section 353 to prevent contact between the fixing ring 35 and the pole 33, while the insulating ring 36 covers a portion of the fixed section 351, allowing it to be exposed for welding to the end cap 32, facilitating operation.

[0064] In the embodiment, the cover plate assembly 3 further comprises a sealing ring 37 sleeved outside the first insulation part 311 and located between the pole 33 and the end cover 32, so as to seal the connection between the pole 33 and the end cover 32. The sealing ring 37 can seal the gap between the end cover 32 and the pole 33, so as to avoid the overflow of the electrolyte and ensure the safety of the battery cell structure. It is worth noting that, although the plastic part can also have a certain sealing effect, the plastic part has a large hardness and poor sealing performance, while the sealing ring 37 can ensure the sealing effect.

[0065] The above is only a preferred embodiment of the present application, and for those skilled in the art, according to the idea of the present application, the specific implementation and application range can be changed, and the content of the specification should not be understood as a limitation of the present application.

Claims

1. A battery cell structure, characterized in that: include: A pole group assembly (2), comprising a pole group body (21) and two pole lug structures (22); A cover plate assembly (3), the cover plate assembly (3) comprising an insulating portion (31), an end cover (32) and two poles (33), the insulating portion (31) comprising a first insulating portion (311) and a second insulating portion (312) connected to each other, the first insulating portion (311) and the second insulating portion (312) being respectively located on opposite sides of the end cover (32), the pole (33) being arranged on a side of the end cover (32) away from the pole group body (21), the first insulating portion (311) being located between the pole (33) and the end cover (32), the second insulating portion (312) being located between the pole group body (21) and the end cover (32), the two pole lug structures (22) being arranged through the insulating portion (31) and the end cover (32) and corresponding to the two poles (33) one by one and being electrically connected.

2. The battery cell structure according to claim 1, characterized in that: The cover plate assembly (3) further includes a shaping plastic part (38), the shaping plastic part (38) being connected to the second insulating part (312), the pole ear structure (22) including a connecting part (221) and a transition part (222), the dimension of the transition part (222) in the thickness direction of the pole group assembly (2) gradually decreasing in a direction close to the connecting part (221), the shaping plastic part (38) is provided with a shaping part on one side facing the pole group assembly (2), the shaping part is provided with a through hole (381), the connecting parts (221) of the two pole ear structures (22) are respectively passed through the corresponding through holes (381) of the shaping plastic part (38), and the shaping part is configured to abut the corresponding transition part (222) to shape the transition part (222).

3. The battery core structure according to claim 2, characterized in that: The shaping portion comprises two shaping surfaces (382) spaced apart and arranged at an angle, the through hole (381) is located between the two shaping surfaces (382), the distance between the two shaping surfaces (382) gradually decreases in a direction approaching the through hole (381), and the shaping surface (382) is configured to press against a surface of the transition portion (222) located on one side of the connecting portion (221).

4. The battery core structure according to claim 2, characterized in that: The shaping plastic part (38) is provided with a buckling groove, and the second insulating portion (312) is arranged in the buckling groove and is interference-fitted with the buckling groove.

5. The battery core structure according to claim 1, characterized in that: The battery cell structure further comprises a shell (1) and a side plate (5); the shell (1) comprises an opening (11) and a bottom plate arranged opposite to each other; the cover plate assembly (3) is connected to the shell (1) to block the opening (11); the side plate (5) is arranged in the shell (1) and is located between the electrode group assembly (2) and the bottom plate.

6. The battery cell structure according to any one of claims 1 to 5, characterized in that: The cover plate assembly (3) further includes a connecting piece (34); the first insulating portion (311) is provided with a connecting groove (313); the connecting piece (34) is arranged in the connecting groove (313); the pole lug structure (22) passes through the insulating portion (31) and is partially bent and then electrically connected to the pole (33) through the connecting piece (34).

7. The battery core structure according to claim 1, characterized in that: The cover plate assembly (3) further comprises a fixing ring (35), wherein the fixing ring (35) is configured to fix the pole (33) to the end cover (32).

8. The battery cell structure according to claim 7, characterized in that: The fixing ring (35) comprises a fixing section (351), a transition section (352) and a pressing section (353); a flange is provided on the outer periphery of the pole (33); the fixing section (351) is fixedly connected to the end cover (32); and the flange is provided between the pressing section (353) and the end cover (32).

9. The battery core structure according to claim 8, characterized in that: The fixing ring (35) is sleeved with an insulating ring (36), and the insulating ring (36) covers the transition section (352), the pressing section (353) and part of the fixing section (351).

10. A battery module, characterized in that: The battery module comprises a plurality of battery cell structures according to any one of claims 1 to 9, and the plurality of battery cell structures are connected in series or in parallel.

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