Battery end cover assembly with safety protection function and battery

Abstract

The utility model provides a battery end cover assembly with a safety protection function and a battery. The battery end cover assembly comprises an end cover body, a riveting block, a pole, an insulating plastic ring and a PTC (Positive Temperature Coefficient) sheet, the end cover body is provided with a first through hole; the riveting block is provided with a second through hole; the terminal post is provided with a step structure, the step structure comprises a step surface which is arranged around the center line of the terminal post and faces upwards or downwards, and the terminal post sequentially penetrates through the first through hole and the second through hole and rivets the end cover body and the riveting block together; the PTC annularly sleeves the pole and is clamped between the step surface and the riveting block, and the upper surface and the lower surface of the PTC are respectively in fit contact with the step surface and the riveting block; and the insulating plastic ring is sleeved on the pole and is arranged between the riveting contact areas of the pole and the riveting block, so that electricity between the pole and the riveting block is conducted only from the PTC. According to the utility model, the risk of fire and explosion of the power battery is reduced, the compactness of the riveting top cover of the power battery is ensured, and the structure is stable.

Description

Technical Field

[0001] This utility model relates to the field of batteries, and in particular to a thermal protection structure for batteries. Background Technology

[0002] Currently, lithium-ion / sodium-ion cylindrical batteries are gradually becoming the mainstream product in the new energy industry due to their high energy density, good capacity consistency, and ability to support high-rate charging and discharging. More and more manufacturers are choosing cylindrical batteries with riveted top covers to reduce costs and increase production capacity. Common issues include: 1. As people's demand for fast charging and rapid travel from cylindrical power batteries increases, higher requirements are also being placed on their safety. Most riveted top cover structures on the market do not have a PTC (Power Transmitter) sensor, which can lead to the battery being unable to self-regulate when experiencing abnormal high temperatures, easily causing fire and explosion risks, endangering personal safety; 2. The riveted top cover structure of cylindrical power batteries has a relatively compact component structure. Incorporating a PTC sensor places higher demands on the battery structure and top cover assembly process.

[0003] Therefore, in the prior art, PTC is generally used in the top cover structure for thermal protection. However, the assembly of PTC is relatively complicated, and the resulting thermal protection structure has poor safety.

[0004] Therefore, there is an urgent need for a battery end cap assembly and battery that can solve the above problems. Utility Model Content

[0005] The purpose of this invention is to provide a battery end cap assembly with safety protection functions, which reduces the risk of fire and explosion of power batteries, while ensuring the compactness and structural stability of the riveted top cover of the power battery.

[0006] To achieve the above objectives, this utility model provides a battery end cap assembly with safety protection function, including an end cap body, a riveting block, a terminal post, an insulating plastic ring, and a PTC. The end cap body has a first through hole; the riveting block has a second through hole; the terminal post has a stepped structure, the stepped structure including a stepped surface arranged around the center line of the terminal post and facing upward or downward, the terminal post passing through the first through hole and the second through hole in sequence and riveting the end cap body and the riveting block together, and the stepped surface is arranged opposite to the upper or lower surface of the terminal post in the vertical direction; the PTC is annularly sleeved on the terminal post and sandwiched between the stepped surface and the riveting block, and the upper and lower surfaces of the PTC are respectively in contact with the stepped surface and the riveting block; the insulating plastic ring is sleeved on the terminal post and disposed between the areas where the terminal post and the riveting block are in contact, so that the electricity between the terminal post and the riveting block is conducted only through the PTC.

[0007] Preferably, the upper surface of the riveting block has a riveting groove for riveting with the pole post, the second through hole is opened at the bottom of the riveting groove, and the insulating plastic ring is disposed between the groove wall of the riveting groove and the outer wall of the pole post; the pole post includes a pole post head located on the side of the end cap body away from the riveting block, a pole post body extending upward from the pole post head and passing through the second through hole, and a riveting head protruding upward from the top of the pole post body and passing through the second through hole before being riveted with the riveting groove, the pole post body and the riveting head forming the stepped structure, the stepped surface facing upward, and the upper and lower surfaces of the PTC respectively adhering to the lower surface of the riveting block and the stepped surface.

[0008] Specifically, the stepped surface has an annular positioning groove recessed on the inner side near the rivet joint for the insertion of the insulating plastic ring, and the end of the insulating plastic ring is inserted into the annular positioning groove.

[0009] Specifically, the insulating plastic ring includes a first portion disposed between the outer wall of the rivet joint and the groove wall of the rivet groove, and a second portion disposed between the outer wall of the rivet joint and the hole wall of the second through hole. More preferably, the second portion further extends downward between the inner wall of the PTC and the outer wall of the rivet joint.

[0010] More preferably, the stepped surface has an annular positioning groove recessed on its inner side near the rivet joint for inserting the insulating plastic ring, the lower end of which is inserted into the annular positioning groove. This facilitates the fixing of the insulating plastic ring and prevents the PTC from contacting the rivet joint in a horizontally opposite direction.

[0011] More preferably, the upper surface of the riveting block has a countersunk hole, the riveting groove is formed on the bottom wall of the countersunk hole, and the insulating plastic ring further includes a third portion that bends and extends from the top of the first portion toward the bottom wall of the countersunk hole. This prevents the insulating plastic ring from sinking and causing contact between the head of the pole riveting and the riveting groove due to prolonged use or stress during riveting.

[0012] More preferably, the bottom of the riveting groove gradually extends downward from the outside to the inside to form a conical groove bottom, and the insulating plastic ring includes a first part disposed between the riveting head and the riveting groove. The area of ​​the first part corresponding to the conical groove bottom is inclined, which facilitates the positioning of the riveting head and prevents the insulating plastic ring from generating unnecessary twisting and wrinkles.

[0013] Preferably, the insulating plastic ring is an integral structure, which facilitates assembly.

[0014] Preferably, it also includes an insulating structure, the insulating structure comprising a first insulating element disposed between the end cap body and the riveting block, and a second insulating element disposed between the pole post and the end cap body.

[0015] Specifically, the lower surface edge of the second insulating member has a downward protruding flange that limits the current collector and the winding core, so that after the battery end cover is assembled and installed on the battery, the second insulating member positions the current collector and the winding core.

[0016] More preferably, the pole includes a pole head located on the side of the end cap body away from the riveting block, and the lower surface of the second insulating member is provided with a limiting protrusion wall protruding downward, and a limiting groove is formed between the limiting protrusion walls to accommodate the pole head, so as to prevent the pole from shifting during riveting.

[0017] More preferably, the upper surface of the second insulating member has one or more protrusions, and the lower surface of the end cap body has one or more limiting grooves that mate with the protrusions. Alternatively, the upper surface of the second insulating member has one or more limiting grooves, and the lower surface of the end cap body has one or more protrusions that mate with the grooves. This design prevents torsion between the second insulating member and the end cap body.

[0018] Preferably, the insulating structure further includes a sealing ring, the sealing ring including a first sealing portion sleeved on the pole and located between the hole wall of the first through hole and the pole, and a second sealing portion formed by bending outward from the lower side of the first sealing portion, the second sealing portion being disposed between the lower surface of the pole and the end cap body.

[0019] Preferably, the riveting block has the riveting groove, and the second through hole is formed at the bottom of the riveting groove; the stepped surface faces upward, and the upper and lower surfaces of the PTC respectively conform to the lower surface of the riveting block and the stepped surface. In this scheme, the pole passes through the end cap body, the PTC, and the relevant through holes on the riveting block from bottom to top and is riveted to the riveting groove of the riveting block, and the stepped surface is formed between the pole body and the riveting head.

[0020] Of course, in another embodiment, the riveting groove can also be formed on the lower surface of the end cap body or the riveting block / current collector located inside the end cap body. In this case, the stepped surface faces downward and is formed between the pole head and the pole body. The pole passes through the through holes of the riveting block, PTC, and end cap body (if there is a riveting block / current collector, it also needs to pass through the through holes on the riveting block / current collector) from top to bottom and is riveted to the downward-opening riveting groove.

[0021] More preferably, the surface of the rivet block that contacts the PTC has a PTC receiving groove to accommodate the PTC, which facilitates the installation and positioning of the PTC.

[0022] More preferably, the insulating structure includes a first insulating member disposed between the end cap body and the riveting block. The first insulating member is annular and surrounds the pole post. The upper surface of the first insulating member also has an annular inner flange protruding between the groove wall of the PTC receiving groove and the side wall of the PTC.

[0023] This utility model also provides a battery, including a battery casing, a battery cell, a current collector, and a battery end cap assembly as described above. The battery cell is installed inside the battery casing, the current collector is electrically connected to the battery cell and the terminal post, and the battery end cap assembly is installed on the battery casing. The end cap body is the cover plate of the battery casing or is integrally formed on the bottom of the battery casing.

[0024] Compared to existing technologies, this invention rivets the connecting block and the cover plate together, then clamps the PTC between the connecting block and the connecting post in the vertical direction. This ensures the PTC is held within the riveting direction of the riveted structure, resulting in a stable and compact structure that is easy to assemble. Furthermore, in the event of abnormally high battery / connecting post temperatures, the PTC can promptly adjust the overcurrent through its own resistance changes, ensuring battery safety. In summary, compared to existing technologies, this invention improves the risk of fire and explosion in power batteries while maintaining the compactness of the riveted top cover, as well as the feasibility and yield of battery manufacturing processes. Attached Figure Description

[0025] Figure 1 This is a perspective view of the battery end cap assembly of this utility model.

[0026] Figure 2 This is an exploded view of the battery end cap assembly of this utility model from one angle.

[0027] Figure 3 This is an exploded view of the battery end cap assembly of this utility model from another angle.

[0028] Figure 4 This is a cross-sectional view of the battery end cap assembly of this utility model.

[0029] Figure 5 yes Figure 4 A magnified view of a portion of the image.

[0030] Figure 6 This is a structural diagram of the insulating plastic ring of this utility model.

[0031] Figure 7 This is a structural diagram of the pole of this utility model.

[0032] Figure 8 yes Figure 1 Enlarged view of part a. Detailed Implementation

[0033] To explain in detail the technical content, structural features, objectives and effects of this utility model, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0034] This utility model discloses a battery, including a battery casing, a battery cell, a current collector, and a battery end cap assembly 100. The battery cell is installed inside the battery casing, the current collector electrically connects the battery cell and the terminal 30, and the battery end cap assembly 100 is installed on the battery casing and closes the battery casing. The battery end cap assembly 100 is cylindrical, serving as the end cap assembly for a cylindrical battery, resulting in a cylindrical battery. However, this application can also be used in prismatic batteries, in which case the battery end cap is square. Alternatively, the end cap body 10 of the battery end cap assembly 100 can be integrally formed with the battery casing, in which case the end cap body 10 serves as the bottom of the battery casing.

[0035] refer to Figures 1 to 5 The battery end cap assembly 100 includes an end cap body 10, a riveting block 20, a terminal post 30, an insulating plastic ring 40, a PTC 50, and an insulating structure 60. The end cap body 10 has a first through hole 11; the riveting block 20 has a second through hole 23; the terminal post 30 passes sequentially through the first through hole 11 and the second through hole 23, riveting the end cap body 10 and the riveting block 20 together. The terminal post 30 and the riveting block 20 have a first region that is vertically opposite each other in a direction perpendicular to the end cap body 10, and a second region that is vertically opposite each other. In this embodiment, the terminal post 30 and the riveting block 20 in the first region are arranged horizontally so that they are vertically opposite each other. The terminal post 30 and the riveting block 20 in the second region are the outer wall of the terminal post 30 and the inner wall of the riveting block, and their extension directions include the vertical direction and also include an inclined direction relative to the vertical direction. The insulating structure 60 includes a first insulating portion 61 disposed between the riveting block 20 and the end cap body 10.

[0036] To facilitate the installation of the PTC50, the lower surface of the rivet block 20 has a PTC receiving groove 24 to accommodate the PTC50, which is partially or completely contained within the PTC receiving groove 24. The PTC50 is a semiconductor material or component with a large positive temperature coefficient; it is a positive temperature coefficient thermistor, and the semiconductor is a ceramic material.

[0037] refer to Figure 5 and Figure 7The riveting block 20 has a riveting groove 22, and the second through hole 23 is opened at the bottom of the riveting groove 22. The pole post 30 includes a pole post head 31 located inside the end cap body 10, a pole post body 32 extending upward from the pole post head 31 and passing through the second through hole 23, and a riveting head 33 protruding upward from the top of the pole post body 32, passing through the second through hole 23, and riveting with the riveting groove 22. During riveting, the riveting head 33 is pressed outward from the riveting hole 332, so that the edge of the riveting head 33 extends outward to form a riveting protrusion 331. There is a stepped structure between the pole post body 32 and the riveting head 33. The first region is formed between the upward-facing stepped surface 321 and the lower surface of the riveting block 20. The second region is formed between the outer wall of the pole post head 31, the inner wall of the second through hole 23, and the inner wall of the riveting groove 22. Of course, the pole head 31 can also be located on the outside of the end cap body 10, in which case the riveting block is located on the inside of the end cap body 10.

[0038] refer to Figure 5 An insulating plastic ring 40 is disposed between the second region of the riveting block 20 and the terminal post 30 to insulate the terminal post 30 and the second region of the riveting block 20 from each other; a PTC 50 is disposed between the first region of the riveting block 20 and the terminal post 30, such that the PTC sheet 50 is respectively attached to the stepped surface 321 of the terminal post 30 and the bottom surface of the riveting block 20 to form a unique overcurrent path (the PTC sheet 50 can directly control the current magnitude from the cell, current collector, terminal post 30 to the riveting block 20 in sequence), so that when the battery / terminal post is at an abnormally high temperature, the PTC sheet (thermometer) can promptly adjust the overcurrent magnitude by changing its own resistance to ensure the safety of the battery. Of course, this is not the only option. In another embodiment, the riveting groove can be provided on the end cap body 10 and facing downwards, or located on a riveting block inside the end cap body 10 and facing downwards. A stepped surface is formed between the pole head and the pole body. The PTC is sandwiched between the pole head and the upper surface of the riveting block. An insulating plastic ring is fitted in the second through hole of the riveting block. To facilitate the placement of the insulating plastic ring, the corresponding positions of the second through hole of the riveting block and the pole body are tapered, gradually decreasing from top to bottom.

[0039] The PTC50 is annular and is fitted onto the electrode post 30 through a central through-hole 51, and is insulated from the electrode post 30 by an insulating plastic ring 40. (Reference) Figure 5 and Figure 6 The insulating plastic ring 40 includes a first portion 41 disposed between the rivet joint 33 and the rivet groove 22, and a second portion 42 disposed between the rivet joint 33 and the second through hole 23. The second portion 42 further extends downward between the inner wall of the PTC50 and the rivet joint 33, such that the inner wall of the PTC50 and the outer wall of the rivet joint 33 are separated by an insulating material.

[0040] Preferably, the bottom of the riveting groove 22 gradually extends downward from the outside to the inside to form a conical bottom. The insulating plastic ring 40 includes a first portion 41 disposed between the riveting head 33 and the riveting groove 22. The area 411 corresponding to the conical bottom of the first portion 41 is inclined, which facilitates the positioning of the riveting head 33 and prevents unnecessary twisting and wrinkling of the insulating plastic ring 40. The insulating plastic ring 40 is an integral structure.

[0041] The riveting block 20 has a countersunk hole 21, and the riveting groove 22 is formed on the bottom wall of the countersunk hole 21. The insulating plastic ring 40 also includes a third part 43 that bends and extends from the top of the first part 41 toward the bottom wall of the countersunk hole 21.

[0042] Preferably, the stepped surface 321 has an annular positioning groove 322 recessed on the inner side near the rivet joint 33 for inserting the insulating plastic ring 40. The lower end of the second part 42 of the insulating plastic ring 40 is inserted into the annular positioning groove 322, which facilitates the fixing of the insulating plastic ring 40 and prevents the PTC50 from contacting the rivet joint 33 in other areas that are not vertically opposite.

[0043] refer to Figures 2 to 5 The insulating structure 60 includes a second insulating member 63 disposed between the pole post 30 and the end cap body 10. The first insulating part 61 has a through hole 611.

[0044] Specifically, the insulating structure 60 further includes a sealing ring 62. The sealing ring 62 includes a first sealing portion 622 sleeved on the pole post 30 and located between the wall of the first through hole 11 and the pole post 30, and a second sealing portion 623 formed by bending outward from the lower side of the first sealing portion 622. The second sealing portion 623 is disposed between the lower surface of the pole post 30 and the end cap body 10. The sealing ring 62 is sleeved on the pole post body 32 of the pole post 30 through the through hole 621.

[0045] Specifically, the lower surface edge of the second insulating member 63 is provided with a lower flange 632 for limiting the current collector and the winding core, so that after the battery end cover is assembled and installed on the battery, the second insulating member 63 positions the current collector and the winding core.

[0046] refer to Figure 5 and Figure 8The lower surface of the second insulating member 63 has a downwardly protruding limiting wall 633, and a limiting groove 634 is formed between the limiting protrusions 633 to accommodate the pole head 31, preventing the pole 30 from shifting during riveting. The second insulating member 63 has a through hole 631, through which the pole 30 sequentially passes to be riveted to the riveting groove 22.

[0047] More preferably, one or more protrusions 635 are provided on the upper surface of the second insulating member 63, and one or more limiting grooves 12 that engage with the protrusions are provided on the lower surface of the end cap body 10. Of course, the positions of the protrusions 635 and the limiting grooves 12 can be interchanged. In this case, one or more limiting grooves are recessed on the upper surface of the second insulating member 63, and one or more protrusions that engage with the grooves are provided on the lower surface of the end cap body 10.

[0048] To facilitate the assembly of the riveting block 20, the first insulating member 61, and the end cap body 10, an insulating member receiving groove 13 is formed on the upper surface of the end cap body 10 to accommodate the first insulating member 61. The first insulating member 61 is at least partially accommodated in the insulating member receiving groove 13. An outer flange 613 protrudes upward from the outer side of the first insulating member 61, and a riveting block receiving groove is formed between the outer flanges 613 to accommodate the riveting block 20. The riveting block 20 is accommodated in the riveting block receiving groove.

[0049] Preferably, in order to further restrict the installation of the rivet block 20 and ensure that the rivet block 20 and PTC50, and the rivet block 20 and pole post 30 are electrically connected only through the depth direction of PTC50, an inner flange 612 protrudes upward from the upper surface of the first insulating member 61 near the through hole 611. A rivet block receiving groove is formed between the outer flange 613 and the inner flange 612, and is an annular groove, so as to restrict the displacement of the rivet block 20 from both inner and outer radial directions and ensure the insulation of the rivet block 20 in the non-horizontal direction.

[0050] The lower surface of the riveting block 20 has a PTC receiving groove 24 for accommodating the PTC50, and the PTC50 is partially or completely accommodated in the PTC receiving groove 24. The inner flange 612 protrudes upward into the PTC receiving groove 24 and is located between the groove wall of the PTC receiving groove 24 and the side wall of the PTC50.

[0051] refer to Figure 2 and Figure 3 The following describes the assembly process of the battery end cap assembly 100 of this utility model:

[0052] First, install the insulating plastic ring 40 in the riveting groove 22, and then place the third part 43 on the top of the riveting groove 22 (the bottom of the countersunk hole 21). Then, the sealing ring 62 is fitted onto the pole body 32, and the PTC50 is fitted onto the pole body 32. The pole 30 with the sealing ring 62 and PTC50 fitted onto it is positioned in the fixture. The second insulating component 63 is fitted onto the pole 30 and positioned using the fixture. The end cap body 10 is fitted onto the pole 30 and positioned using the fixture. The first insulating component 61 is fitted onto the pole and positioned using the fixture. The riveting block 20 with the insulating plastic ring 40 fitted onto the pole 30 is positioned using the fixture. The riveting head 33 is deformed through the riveting hole 332 to form the riveting protrusion 331. During the riveting process, the sealing ring 62 compresses and seals the pole 30 and the end cap body 10. At the same time, the upper and lower sides of the PTC50 are respectively attached to the stepped surface 321 and the bottom of the PTC receiving groove 24 in the riveting block 20, and are clamped between the two.

[0053] In this embodiment, the end cap body 10 is an aluminum shell or a steel shell, and the riveting block 20 is made of aluminum, iron, or a composite material. The pole post is a copper post.

[0054] In this invention, the vertical and horizontal positions are relative, not absolute. In this embodiment, the extension direction of the end cap body or the bottom shell of the battery case is horizontal, and the vertical direction is perpendicular to the horizontal direction.

[0055] The above-disclosed embodiments are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent variations made in accordance with the scope of the present utility model application shall still fall within the scope of the present utility model.

Claims

1. A battery end cap assembly with safety protection function, characterized in that: include: The end cap body has a first through hole; The riveting block has a second through hole; The pole post has a stepped structure, the stepped structure including a stepped surface arranged around the center line of the pole post and facing upward or downward, the pole post passing through the first through hole and the second through hole in sequence and riveting the end cap body and the riveting block together, and the stepped surface is arranged opposite to the upper surface or lower surface of the pole post in the vertical direction. The PTC is annularly sleeved on the pole post and sandwiched between the stepped surface and the rivet block, with the upper and lower surfaces of the PTC respectively in contact with the stepped surface and the rivet block. An insulating plastic ring is sleeved on the pole and positioned between the pole and the riveting block in the riveting contact area, so that the electricity between the pole and the riveting block is conducted only through the PTC.

2. The battery end cap assembly as described in claim 1, characterized in that: The upper surface of the rivet block has a rivet groove for riveting with the pole post. The second through hole is opened at the bottom of the rivet groove. The insulating plastic ring is disposed between the groove wall of the rivet groove and the outer wall of the pole post. The pole post includes a pole head located on the side of the end cap body away from the rivet block, a pole body extending upward from the pole head and passing through the second through hole, and a rivet head extending upward from the top of the pole body and passing through the second through hole before being riveted with the rivet groove. The pole body and the rivet head form the stepped structure. The stepped surface faces upward. The upper and lower surfaces of the PTC are respectively attached to the lower surface of the rivet block and the stepped surface.

3. The battery end cap assembly as described in claim 2, characterized in that: The stepped surface has an annular positioning groove recessed on the inner side near the rivet joint for inserting the insulating plastic ring, and the end of the insulating plastic ring is inserted into the annular positioning groove.

4. The battery end cap assembly as described in claim 2, characterized in that: The insulating plastic ring includes a first portion disposed between the outer wall of the rivet joint and the groove wall of the rivet groove, and a second portion disposed between the outer wall of the rivet joint and the hole wall of the second through hole.

5. The battery end cap assembly as described in claim 4, characterized in that: The end of the second part also extends between the inner wall of the PTC and the outer wall of the rivet.

6. The battery end cap assembly as described in claim 4, characterized in that: The upper surface of the rivet block has a countersunk hole, the rivet groove is formed on the bottom wall of the countersunk hole, and the insulating plastic ring also includes a third part that bends and extends from the top of the first part to the bottom wall of the countersunk hole.

7. The battery end cap assembly as described in claim 3, characterized in that: The bottom of the riveting groove gradually extends downward from the outside to the inside to form a conical groove bottom. The insulating plastic ring includes a first part disposed between the riveting head and the riveting groove. The area of ​​the first part corresponding to the conical groove bottom is inclined.

8. The battery end cap assembly as claimed in claim 1, characterized in that: The insulating plastic ring is a one-piece structure.

9. The battery end cap assembly as claimed in claim 1, characterized in that: It also includes an insulation structure, which includes a first insulating member disposed between the end cap body and the riveting block, and a second insulating member disposed between the pole post and the end cap body.

10. The battery end cap assembly as claimed in claim 9, characterized in that: The lower surface edge of the second insulating member is provided with a lower flange for limiting current collector and winding core.

11. The battery end cap assembly as claimed in claim 9, characterized in that: The pole includes a pole head located on the side of the end cap body away from the rivet block, and the lower surface of the second insulating member is provided with a limiting protrusion wall protruding downward, and a limiting groove for accommodating the pole head is formed between the limiting protrusion walls.

12. The battery end cap assembly as claimed in claim 1, characterized in that: The surface of the rivet block that contacts the PTC has a PTC receiving groove to accommodate the PTC.

13. The battery end cap assembly as claimed in claim 12, characterized in that: It also includes an insulating structure, which includes a first insulating member disposed between the end cap body and the riveting block. The first insulating member is annular and surrounds the pole post. The upper surface of the first insulating member also has an annular inner flange protruding between the groove wall of the PTC receiving groove and the side wall of the PTC.

14. A battery, characterized in that: The battery includes a battery casing, a battery cell, a current collector, and a battery end cap assembly as described in any one of claims 1-13, wherein the battery cell is installed inside the battery casing, the current collector is electrically connected to the battery cell and the terminal post, the battery end cap assembly is installed on the battery casing, and the end cap body is a cover plate of the battery casing or integrally formed on the bottom of the battery casing.

Images