Cylindrical battery and battery module

Abstract

The utility model provides a cylindrical battery and battery module, cylindrical battery includes head cover subassembly and shell, the head cover subassembly includes cap, insulation heat conduction structure and heat dissipation metal sheet, the cap and the shell are mutually insulated and sealed, the cap is the positive pole or the negative pole of the cylindrical battery, and the heat dissipation metal sheet is the heat dissipation metal sheet. The heat dissipation metal sheet is connected with the cap, and the insulating heat conduction structure is located between the heat dissipation metal sheet and the shell. According to the cylindrical battery provided by the utility model, the heat dissipation metal sheet is connected with the cover cap, so that heat conduction between the heat dissipation metal sheet and the cover cap is further realized, and the insulating heat conduction structure is arranged between the heat dissipation metal sheet and the shell, so that the shell carries out heat conduction through the insulating heat conduction structure, and a complete and efficient heat dissipation network is formed; the heat generated at the cap can be conducted out more effectively, so that the heat cannot be accumulated in the battery, chemical reaction balance in the battery can be maintained favorably, and negative effects on the battery performance due to heat accumulation are avoided.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to a cylindrical battery and a battery module. Background Technology

[0002] With the rapid development of the new energy industry, the application scenarios of lithium-ion batteries have expanded from consumer electronics to electric vehicles, energy storage systems, and other fields. Different application scenarios place higher demands on the performance and safety of lithium-ion batteries, making heat dissipation a crucial factor affecting the overall performance and safety of the batteries.

[0003] Lithium-ion batteries generally consist of a top cover assembly, a casing, and a cell. The top cover assembly and the casing form a space to house the cell. The top cover assembly of a cylindrical battery is assembled by stacking a steel cap, an explosion-proof aluminum sheet, an insulating ring, a connecting aluminum sheet, and a sealing ring in sequence. When the top cover assembly is assembled onto the cylindrical battery, the connecting aluminum sheet is welded to the cell tabs to complete electrical and thermal conduction. However, the steel cap of the top cover assembly does not form a thermal conductive network with the casing. During battery operation, a large current passes through the terminals, causing them to generate high temperatures. If this heat cannot be dissipated in time, it will accumulate inside the battery, thereby affecting the chemical reaction balance inside the battery, accelerating battery aging, reducing battery life, and even causing safety accidents such as battery thermal runaway. Utility Model Content

[0004] The technical problem to be solved by this utility model is to address the issue that cylindrical batteries in the prior art cannot form an efficient heat dissipation network, and to provide a cylindrical battery and battery module.

[0005] The technical solution adopted by this utility model to solve the above-mentioned technical problems is as follows:

[0006] A cylindrical battery is provided, including a top cover assembly and a housing. The top cover assembly includes a cap, an insulating and thermally conductive structure, and a heat dissipation metal sheet. The cap and the housing are mutually insulated and sealed. The cap is the positive or negative electrode of the cylindrical battery. The heat dissipation metal sheet is connected to the cap. The insulating and thermally conductive structure is located between the heat dissipation metal sheet and the housing. The insulating and thermally conductive structure is thermally connected to the cap and the housing.

[0007] Optionally, it also includes explosion-proof valve holes, which include a first explosion-proof valve hole, a second explosion-proof valve hole, and a third explosion-proof valve hole. The first explosion-proof valve hole is disposed on the cap, the second explosion-proof valve hole is disposed on the insulating and heat-conducting structure, and the third explosion-proof valve hole is disposed on the heat dissipation metal plate. The second explosion-proof valve hole and the third explosion-proof valve hole correspond one-to-one with the first explosion-proof valve hole in the axial direction of the cylindrical battery.

[0008] Optionally, the insulating and heat-conducting structure is provided with a through hole, which is a clearance hole for the connection between the cap and the insulating and heat-conducting structure, and the heat dissipation metal sheet is thermally connected to the insulating and heat-conducting structure.

[0009] Optionally, the top cover assembly further includes a sealing ring disposed between the cap and the housing, the sealing ring being used to seal the assembly gap between the cap and the housing.

[0010] Optionally, the cap includes a sheet-like structure, and the housing includes an extension that extends beyond the sheet-like structure and abuts against the insulating and thermally conductive structure.

[0011] Optionally, the top cover assembly further includes a first aluminum sheet, a second aluminum sheet, and a spacer ring. The first aluminum sheet is disposed on the side of the cap facing the housing, and a thin-walled protrusion is provided on the first aluminum sheet facing away from the cap. The second aluminum sheet is disposed on the side of the first aluminum sheet facing away from the cap, and the thin-walled protrusion abuts against the second aluminum sheet. The spacer ring is disposed between the first aluminum sheet and the second aluminum sheet to isolate the first aluminum sheet and the second aluminum sheet. A connecting hole is provided on the second aluminum sheet.

[0012] Optionally, the second aluminum sheet is also provided with an injection hole for injecting electrolyte.

[0013] Optionally, the cylindrical battery further includes a cell and a tab, the tab being disposed at one end of the cell, and the second aluminum sheet being welded to the tab.

[0014] Optionally, the housing is a semi-enclosed cylindrical housing with one end open, the battery cell is placed in the housing, and the top cover assembly closes the opening of the housing.

[0015] Optionally, the cylindrical battery further includes a winding needle disposed in the housing and extending from one end of the housing to the opening end of the housing. The winding needle does not protrude from the end of the opening end of the housing. The battery cell is provided with a mounting hole that passes through both ends of the battery cell, and the winding needle is inserted into the mounting hole.

[0016] On the other hand, this application provides a battery module, including the cylindrical battery and a connector, wherein the connector is electrically connected to the heat dissipation metal sheet.

[0017] The beneficial effects of this utility model are as follows:

[0018] The cylindrical battery provided in this application has a top cover assembly including a cap serving as the positive or negative electrode, an insulating and thermally conductive structure, and a heat dissipation metal sheet. The heat dissipation metal sheet is connected to the cap, thereby achieving heat conduction between the heat dissipation metal sheet and the cap. Furthermore, an insulating and thermally conductive structure is provided between the heat dissipation metal sheet and the casing, allowing the casing to conduct heat through the insulating and thermally conductive structure, forming a complete and efficient heat dissipation network. This network can more effectively conduct away the heat generated at the cap, preventing heat from accumulating inside the battery. This helps maintain the chemical reaction balance inside the battery and avoids negative impacts on battery performance due to heat accumulation. Attached Figure Description

[0019] Figure 1 This is an exploded view of the cylindrical battery provided by this utility model;

[0020] Figure 2 This is a schematic diagram of the cross-sectional structure of the cylindrical battery provided by this utility model;

[0021] Figure 3 This is a schematic diagram of the cylindrical battery structure provided by this utility model.

[0022] The reference numerals in the accompanying drawings are as follows:

[0023] 1. Battery cell; 11. Sealing ring; 12. First aluminum sheet; 13. Second aluminum sheet; 131. Connecting hole; 132. Liquid injection hole; 14. Insulating ring; 2. Housing; 3. Cap; 4. Insulating and heat-conducting structure; 41. Through hole; 5. Heat dissipation metal sheet; 6. Explosion-proof valve hole; 61. First explosion-proof valve hole; 62. Second explosion-proof valve hole; 63. Third explosion-proof valve hole; 7. Tab; 8. Coil needle; 9. Cylindrical battery; 10. Sheet structure; 15. Extension. Detailed Implementation

[0024] To make the technical problems solved, technical solutions, and beneficial effects of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0025] In the description of this utility model, it should be understood that the terms "longitudinal," "radial," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0026] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0027] Reference Figure 1-3 This utility model provides a cylindrical battery 9, including a top cover assembly and a housing 2. The top cover assembly includes a cap 3, an insulating and thermally conductive structure 4, and a heat dissipation metal sheet 5. The cap 3 and the housing 2 are mutually insulated and sealed. The cap 3 is the positive or negative electrode of the cylindrical battery 9. The heat dissipation metal sheet 5 is connected to the cap 3. The insulating and thermally conductive structure 4 is located between the heat dissipation metal sheet 5 and the housing 2. The insulating and thermally conductive structure 4 is thermally connected to the cap 3 and the housing 2.

[0028] Specifically, the cylindrical battery 9 provided in this application includes a top cover assembly comprising a cap 3 serving as the positive or negative electrode, an insulating and thermally conductive structure 4, and a heat dissipation metal sheet 5. The heat dissipation metal sheet 5 is connected to the cap 3, thereby achieving heat conduction between the heat dissipation metal sheet 5 and the cap 3. Furthermore, an insulating and thermally conductive structure 4 is provided between the heat dissipation metal sheet 5 and the casing 2, allowing the casing 2 to conduct heat through the insulating and thermally conductive structure 4, forming a complete and efficient heat dissipation network. This network can more effectively conduct away the heat generated at the cap 3, preventing heat accumulation inside the battery and helping to maintain the chemical reaction balance inside the battery, thus avoiding negative impacts on battery performance due to heat accumulation.

[0029] In one embodiment, the system further includes an explosion-proof valve hole 6, which includes a first explosion-proof valve hole 61, a second explosion-proof valve hole 62, and a third explosion-proof valve hole 63. The first explosion-proof valve hole 61 is disposed on the cap 3, the second explosion-proof valve hole 62 is disposed on the insulating and heat-conducting structure 4, and the third explosion-proof valve hole 63 is disposed on the heat dissipation metal sheet 5. The second explosion-proof valve hole 62 and the third explosion-proof valve hole 63 correspond one-to-one with the first explosion-proof valve hole 61 in the axial direction of the cylindrical battery 9.

[0030] Specifically, the first explosion-proof valve hole 61 is located on the cap 3, the second explosion-proof valve hole 62 is located on the insulating and heat-conducting structure 4, and the third explosion-proof valve hole 63 is located on the heat dissipation metal plate 5. The first explosion-proof valve hole 61, the second explosion-proof valve hole 62, and the third explosion-proof valve hole 63 correspond one-to-one in the axial direction, forming a vertically penetrating pressure relief channel. When the internal pressure of the battery rises suddenly due to abnormal conditions such as overcharging or overheating, the gas can be quickly discharged through the three valve holes, avoiding the risk of blockage or failure of a single pressure relief point, shortening the pressure relief time, and reducing the probability of explosion or fire.

[0031] In one embodiment, the insulating heat-conducting structure 4 is provided with a through hole 41, which is a clearance hole for the connection between the cap 3 and the insulating heat-conducting structure 4, and the heat dissipation metal sheet 5 is thermally connected to the insulating heat-conducting structure (4).

[0032] Specifically, the through hole 41 serves as a clearance hole for the cap 3, allowing the cap and the insulating heat-conducting structure 4 to form an annular contact interface around the hole, ensuring that the heat generated by the cap can be directly transferred to the insulating heat-conducting structure 4 through heat conduction, thus shortening the heat transfer distance.

[0033] The insulating and heat-conducting structure 4 has the function of electrical insulation, which can block the direct electrical connection between the cap 3 and the heat dissipation metal plate 5 and the shell 2 (usually the negative pole or ground), and prevent short circuit between the positive and negative poles.

[0034] In one embodiment, the cap 3 includes a sheet structure 10, and the housing 2 includes an extension 15, the extension 15 extending beyond the sheet structure 10 and abutting against the insulating and thermally conductive structure 4.

[0035] The extension 15 of the housing 2 extends beyond the sheet structure 10 of the cap 3, allowing the extension 15 to directly contact the insulating and heat-conducting structure 4. This arrangement shortens the heat conduction distance between the housing 2 and the insulating and heat-conducting structure 4. In addition, the extension 15 extending beyond the sheet structure 10 provides mechanical support for the insulating and heat-conducting structure 4, preventing it from shifting or deforming due to force during battery assembly or charging and discharging, thus ensuring the long-term reliability of the heat conduction path.

[0036] In one embodiment, the top cover assembly further includes a sealing ring 11 disposed between the cap 3 and the housing 2, the sealing ring 11 being used to seal the assembly gap between the cap 3 and the housing 2.

[0037] Specifically, the sealing ring 11 fills the assembly gap between the cap 3 and the housing 2, forming an annular sealing interface, which effectively prevents the electrolyte inside the battery from leaking due to vibration, compression, or thermal expansion and contraction. At the same time, external impurities (moisture, dust) have difficulty penetrating into the battery through the sealing interface, avoiding electrolyte contamination or electrode corrosion, and extending the battery's service life.

[0038] In one embodiment, the heat dissipation metal sheet 5 includes an aluminum sheet or a copper sheet.

[0039] Specifically, the heat dissipation metal sheet 5 forms a three-dimensional heat conduction network in the cylindrical battery 9, consisting of a cap 3, a heat-conducting metal sheet, an insulating heat-conducting structure 4, and a shell 2. The aluminum / copper material of the aluminum or copper sheet acts as a good conductor and can be in close contact with the insulating heat-conducting structure 4, reducing interface thermal resistance and improving overall heat dissipation efficiency.

[0040] In one embodiment, the top cover assembly further includes a first aluminum sheet 12, a second aluminum sheet 13, and an insulating ring 14. The first aluminum sheet 12 is disposed on the side of the cap 3 facing the housing 2, and the first aluminum sheet 12 is provided with a thin-walled protrusion facing away from the cap 3. The second aluminum sheet 13 is disposed on the side of the first aluminum sheet 12 facing away from the cap 3, and the thin-walled protrusion abuts against the second aluminum sheet 13. The insulating ring 14 is disposed between the first aluminum sheet 12 and the second aluminum sheet 13 to isolate the first aluminum sheet 12 and the second aluminum sheet 13. The second aluminum sheet 13 is provided with a connecting hole 131.

[0041] Specifically, a thin-walled protrusion is provided on the first aluminum sheet 12 in a direction away from the cap 3. When the cylindrical battery 9 has a large pressure and needs to be depressurized, the internal air pressure of the battery breaks through the thin-walled protrusion of the first aluminum sheet 12 through the connecting hole 131 on the second aluminum sheet 13 to release the pressure.

[0042] The thin-walled protrusions on the first aluminum sheet 12 abut against the second aluminum sheet 13, forming a point-to-surface heat conduction interface. The first aluminum sheet 12 quickly absorbs the heat generated by the cap 3 and enhances the heat conduction efficiency through the thin-walled protrusions, shortening the path of heat transfer from the cap 3 to the second aluminum sheet 13. In addition, the first aluminum sheet 12 directly contacts the cap 3, quickly capturing the heat source, while the second aluminum sheet 13 receives the heat through the protrusions and diffuses it outward, forming a double-layer heat conduction network, which significantly improves heat transfer.

[0043] The insulating ring 14 is disposed between the first aluminum sheet 12 and the second aluminum sheet 13, which can limit the relative displacement between the two and prevent the aluminum sheets from being misaligned or poorly contacted due to changes in internal pressure during battery charging and discharging, thus ensuring the stability of the heat conduction path.

[0044] In one embodiment, the second aluminum sheet 13 is further provided with an injection hole 132 for injecting electrolyte.

[0045] In one embodiment, the cylindrical battery 9 further includes a cell 1 and a tab 7, the tab 7 being disposed at one end of the cell 1, and the second aluminum sheet 13 being welded to the tab 7.

[0046] Specifically, the tab 7, as one of the heat-generating areas of the electrochemical reaction inside the cell 1, is directly connected to the second aluminum sheet 13 by welding. This allows heat to be quickly conducted along the path of tab 7-second aluminum sheet 13-first aluminum sheet 12-insulating thermally conductive structure 4-shell 2, shortening the heat transfer distance. Compared with the traditional design where the tab 7 is only connected to the cap 3, the dual aluminum sheet structure forms a parallel heat dissipation channel, which can simultaneously conduct the heat from the tab 7 to both sides of the cap 3 and the shell 2, improving heat dissipation efficiency. In addition, the second aluminum sheet 13, as a planar heat dissipation carrier, can evenly diffuse the locally concentrated heat from the tab 7 to the entire top cover assembly, avoiding the occurrence of temperature hotspots near the tab 7. This helps to improve the overall temperature uniformity of the cell 1 and avoid the problem of local high temperature in the cylindrical battery 9.

[0047] In one embodiment, the housing 2 is a semi-enclosed cylindrical housing 2 with one end open, the battery cell 1 is placed in the housing 2, and the top cover assembly closes the opening of the housing 2.

[0048] Specifically, the battery cell 1 is inserted into the housing 2 through the open end of the cylindrical housing 2, and then the open end of the cylindrical housing 2 is closed by the top cover assembly to form a cylindrical battery 9. The cylindrical battery 9 provided in this application has a top cover assembly including a cap 3 as a positive or negative electrode, an insulating and thermally conductive structure 4, and a heat dissipation metal sheet 5. The heat dissipation metal sheet 5 is connected to the cap 3 to achieve heat conduction between the heat dissipation metal sheet 5 and the cap 3. Furthermore, an insulating and thermally conductive structure 4 is provided between the heat dissipation metal sheet 5 and the housing 2 so that the housing 2 can conduct heat through the insulating and thermally conductive structure 4, forming a complete and efficient heat dissipation network. This can more effectively conduct away the heat generated at the cap 3, preventing heat from accumulating inside the battery. This helps maintain the chemical reaction balance inside the battery and avoids negative impacts on battery performance due to heat accumulation.

[0049] Reference Figure 2In one embodiment, the cylindrical battery 9 further includes a winding needle 8, which is disposed in the housing 2 and extends from one end of the housing 2 toward the opening end of the housing 2. The winding needle 8 does not protrude from the end of the opening end of the housing 2. The battery cell 1 is provided with a mounting hole that passes through both ends of the battery cell 1, and the winding needle 8 is inserted into the mounting hole.

[0050] Specifically, after the coil needle 8 is inserted into the mounting hole of the battery cell 1, it forms a rigid support shaft that runs through both ends of the battery cell 1. This can effectively resist the axial expansion force caused by lithium dendrite growth and electrolyte penetration during the charging and discharging process of the battery cell 1, prevent the battery cell 1 from bulging, wrinkling and other deformations, maintain the uniformity of the electrode spacing and reduce the risk of internal short circuit.

[0051] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A cylindrical battery, characterized in that, The device includes a top cover assembly and a housing (2). The top cover assembly includes a cap (3), an insulating and thermally conductive structure (4), and a heat dissipation metal sheet (5). The cap (3) is mutually insulated and sealed from the housing (2). The cap (3) is the positive or negative electrode of the cylindrical battery (9). The heat dissipation metal sheet (5) is connected to the cap (3). The insulating and thermally conductive structure (4) is located between the heat dissipation metal sheet (5) and the housing (2). The insulating and thermally conductive structure (4) is thermally connected to the cap (3) and the housing (2).

2. The cylindrical battery according to claim 1, characterized in that, It also includes an explosion-proof valve hole (6), which includes a first explosion-proof valve hole (61), a second explosion-proof valve hole (62) and a third explosion-proof valve hole (63). The first explosion-proof valve hole (61) is disposed on the cap (3), the second explosion-proof valve hole (62) is disposed on the insulating heat-conducting structure (4), and the third explosion-proof valve hole (63) is disposed on the heat dissipation metal plate (5). The second explosion-proof valve hole (62) and the third explosion-proof valve hole (63) correspond one-to-one with the first explosion-proof valve hole (61) in the axial direction of the cylindrical battery (9).

3. The cylindrical battery according to claim 1, characterized in that, The insulating and heat-conducting structure (4) is provided with a through hole (41), which is a clearance hole for the connection between the cap (3) and the insulating and heat-conducting structure (4). The heat dissipation metal sheet (5) is thermally connected to the insulating and heat-conducting structure (4).

4. The cylindrical battery according to claim 1, characterized in that, The cap (3) includes a sheet structure (10), and the housing (2) includes an extension (15) extending beyond the sheet structure (10) and abutting against the insulating and heat-conducting structure (4).

5. The cylindrical battery according to claim 1, characterized in that, The top cover assembly also includes a sealing ring (11), which is disposed between the cap (3) and the housing (2) and is used to seal the assembly gap between the cap (3) and the housing (2).

6. The cylindrical battery according to claim 1, characterized in that, The top cover assembly also includes a first aluminum sheet (12), a second aluminum sheet (13), and an isolation ring (14). The first aluminum sheet (12) is disposed on the side of the cap (3) facing the housing (2). The first aluminum sheet (12) has a thin-walled protrusion facing away from the cap (3). The second aluminum sheet (13) is disposed on the side of the first aluminum sheet (12) facing away from the cap (3), and the thin-walled protrusion abuts against the second aluminum sheet (13). The isolation ring (14) is disposed between the first aluminum sheet (12) and the second aluminum sheet (13) to isolate the first aluminum sheet (12) and the second aluminum sheet (13). The second aluminum sheet (13) has a connecting hole (131).

7. The cylindrical battery according to claim 6, characterized in that, The cylindrical battery (9) also includes a cell (1) and a tab (7). The tab (7) is disposed at one end of the cell (1), and the second aluminum sheet (13) is welded to the tab (7).

8. The cylindrical battery according to claim 7, characterized in that, The housing (2) is a semi-closed cylindrical housing (2) with one end open. The battery cell (1) is placed in the housing (2). The top cover assembly closes the opening of the housing (2).

9. The cylindrical battery according to claim 8, characterized in that, The cylindrical battery (9) also includes a winding needle (8), which is disposed in the housing (2) and extends from one end of the housing (2) toward the opening end of the housing (2). The winding needle (8) does not protrude from the end of the opening end of the housing (2). The battery cell (1) is provided with a mounting hole, which passes through both ends of the battery cell (1). The winding needle (8) is inserted into the mounting hole.

10. A battery module, characterized in that, It includes the cylindrical battery (9) according to any one of claims 1-9 and a connector, the connector being electrically connected to the heat dissipation metal sheet (5).

Images