Cylindrical battery cover assembly and battery

Abstract

The present invention relates to the technical field of new energy batteries, and discloses a cylindrical battery cover assembly and a battery. The cylindrical battery cover assembly has good heat dissipation performance in the pole ear connection area, reduces the problem of heat concentration, prolongs the battery life, and can ensure the current capacity of the pole ear connection area, thereby improving the battery performance. The cylindrical battery cover assembly of the present invention is applied to a battery, the battery includes a battery cell, the battery cell includes a pole ear, the pole ear includes a positive pole ear and a negative pole ear, and the positive pole ear and the negative pole ear are arranged on the same side of the battery cell; the cylindrical battery cover assembly includes: a pole and a current collector, the current collector includes a pole ear connection area and a pole column connection area, the pole ear connection area is connected to the pole ear, and the pole column connection area is connected to the pole column to realize the electrical connection between the pole ear and the pole column, the thickness of the pole column connection area is a, the thickness of the pole ear connection area is b, and the ratio of thickness b to thickness a satisfies 0.2≤b / a<1.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy batteries, and in particular to a cylindrical battery cover assembly and a battery. Background Art

[0002] Cylindrical battery is a kind of battery with high capacity, long cycle life and wide operating temperature range, and is widely used. The positive and negative electrodes of cylindrical battery are led out on the same side, and the current collector in its cover assembly needs to be welded with the tabs and poles. During the tab welding and battery operation, a lot of heat is generated at the tabs and current collectors. If the thickness of the current collector is too thick, the heat in the tab connection area of ​​the current collector is concentrated and the heat dissipation performance is poor. If the thickness of the current collector is too thin, it will affect the current flow capacity of the tab connection area and affect the battery performance. Therefore, the existing current collectors cannot meet the requirements. Summary of the invention

[0003] In view of this, the present invention provides a cylindrical battery cover assembly and a battery to solve the problem that if the thickness of the current collector of the existing battery is too thin, the heat dissipation performance is poor, and if the thickness of the current collector is too thick, the current flow capacity is poor.

[0004] In a first aspect, the present invention provides a cylindrical battery cover assembly, which is applied to a battery, wherein the battery comprises a battery cell, the battery cell comprises a tab, the tab comprises a positive tab and a negative tab, and the positive tab and the negative tab are arranged on the same side of the battery cell; the cylindrical battery cover assembly comprises:

[0005] Pole;

[0006] A current collector comprises a pole lug connection area and a pole post connection area, wherein the pole lug connection area is connected to the pole lug, and the pole post connection area is connected to the pole post, so as to realize electrical connection between the pole lug and the pole post, the thickness of the pole post connection area is a, the thickness of the pole lug connection area is b, and the ratio of thickness b to thickness a satisfies 0.2≤b / a<1.

[0007] Beneficial effects: The cover plate assembly of the present invention includes a pole and a current collector, the current collector includes a pole lug connection area and a pole column connection area, the pole lug connection area is connected to the pole lug, the pole column connection area is connected to the pole column, and the ratio of the thickness b of the pole lug connection area to the thickness a of the pole column connection area satisfies 0.2≤b / a<1. If the ratio of the thickness b of the pole lug connection area to the thickness a of the pole column connection area is higher than the above range, the thickness of the pole lug connection area is too thick, which will lead to poor heat dissipation performance of the pole lug connection area, and if the ratio of the thickness b of the pole lug connection area to the thickness a of the pole column connection area is lower than the above range, the thickness of the pole lug connection area is too thin, which will affect the current flow capacity of the pole lug connection area.

[0008] In the present application, the thickness of the current collector is not uniform, but the thickness of the pole ear connection area is thinner than that of the pole column connection area. Since the distance between the pole ear connection area and the cover plate body in the cover plate assembly is far, the heat dissipation of the pole ear connection area is poor. When the ratio of the thickness b of the pole ear connection area to the thickness a of the pole column connection area satisfies 0.2≤b / a<1, the heat dissipation capacity of the current collector can be balanced, so that the heat dissipation performance of the pole ear connection area is better. During the operation of the battery, a large amount of heat generated by the pole ear can be dissipated through the pole ear connection area of ​​the current collector, so that the pole ear and the pole ear connection area are cooled, the problem of heat concentration is reduced, the battery service life is extended, and the current flow capacity of the pole ear connection area can be guaranteed, thereby improving the battery performance.

[0009] In a second aspect, the present invention provides a battery, comprising a cylindrical battery cover assembly and a battery cell as described above, wherein the battery cell comprises a pole ear, wherein the pole ear is connected to a pole ear connection area of ​​a current collector in the cover assembly, an orthographic projection area of ​​the pole ear on the current collector is c, an area of ​​the pole ear connection area is d, and a ratio of area c to area d satisfies 0.5≤c / d<1.

[0010] Because the battery of the present invention has the cylindrical battery cover assembly of the present invention, it has the same beneficial effects as the cylindrical battery cover assembly, which will not be described in detail. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0012] Figure 1 It is an exploded schematic diagram of the cover plate assembly of the present invention (partial structure is hidden);

[0013] Figure 2 is a cross-sectional view of a cover plate assembly of the present invention;

[0014] Figure 3 is a schematic diagram of a current collecting member in a cover plate assembly of the present invention;

[0015] Figure 4 It is an exploded schematic diagram of the current collecting member in the cover plate assembly of the present invention;

[0016] Figure 5 Schematic diagram of the battery of the present invention.

[0017] Description of reference numerals:

[0018] 1. Current collecting parts;

[0019] 2. positive electrode current collector; 201. positive electrode ear connection area; 202. positive electrode column connection area; 203. connection plate;

[0020] 3. Negative electrode current collector; 301. Negative electrode tab connection area; 302. Negative electrode column connection area;

[0021] 4. Positive pole (cover body);

[0022] 5. Negative pole;

[0023] 6. Groove;

[0024] 7. Raised part;

[0025] 8. Insulating member; 801. First hollow portion; 802. Second hollow portion;

[0026] 9. Battery casing;

[0027] 10. Flanging. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0029] Combine the following Figure 1-Figure 5 , describing embodiments of the cylindrical battery cover assembly and battery of the present invention.

[0030] According to an embodiment of the present invention, on the one hand, a cylindrical battery cover assembly is provided, which is applied to a battery, wherein the battery includes a battery cell, the battery cell includes a pole tab, the pole tab includes a positive pole tab and a negative pole tab, and the positive pole tab and the negative pole tab are arranged on the same side of the battery cell; the cylindrical battery cover assembly includes: a pole column and a current collector 1, the current collector 1 includes a pole tab connection area and a pole column connection area, the pole tab connection area is connected to the pole tab, and the pole column connection area is connected to the pole column to realize electrical connection between the pole tab and the pole column, the thickness of the pole column connection area is a, the thickness of the pole tab connection area is b, and the ratio of thickness b to thickness a satisfies 0.2≤b / a<1.

[0031] The cover plate assembly includes a pole and a current collector, the current collector 1 includes a pole lug connection area and a pole lug connection area, the pole lug connection area is connected to the pole lug, the pole lug connection area is connected to the pole lug, and the ratio of the thickness b of the pole lug connection area to the thickness a of the pole lug connection area satisfies 0.2≤b / a<1. If the ratio of the thickness b of the pole lug connection area to the thickness a of the pole lug connection area is higher than the above range, the thickness of the pole lug connection area is too thick, which will lead to poor heat dissipation performance of the pole lug connection area, and if the ratio of the thickness b of the pole lug connection area to the thickness a of the pole lug connection area is lower than the above range, the thickness of the pole lug connection area is too thin, which will affect the current flow capacity of the pole lug connection area.

[0032] However, the thickness of the current collector 1 in the present application is not uniform, but the thickness of the pole ear connection area is thinner than that of the pole column connection area. Since the distance between the pole ear connection area and the cover plate body in the cover plate assembly is relatively far, the heat dissipation of the pole ear connection area is relatively poor. When the ratio of the thickness b of the pole ear connection area to the thickness a of the pole column connection area satisfies 0.2≤b / a<1, the heat dissipation capacity of the current collector can be balanced, so that the heat dissipation performance of the pole ear connection area is better. During the operation of the battery, a large amount of heat generated by the pole ear can be dissipated through the pole ear connection area of ​​the current collector, so that the pole ear and the pole ear connection area are cooled down, the problem of heat concentration is reduced, the battery service life is extended, and the current flow capacity of the pole ear connection area can be guaranteed, thereby improving the battery performance.

[0033] The cylindrical battery cover assembly of this embodiment is applied to a battery with positive and negative electrodes led out on the same side, and the battery is specifically a cylindrical battery, which includes a battery cell, and the battery cell includes a tab, and the tab includes a positive tab and a negative tab, and the positive tab and the negative tab are arranged on the same side of the battery cell to achieve the same-side lead-out of the positive and negative electrodes of the battery. The cylindrical battery with the positive and negative electrodes led out on the same side has a compact structure and a small volume, and the volume of the structures such as the current collector 1 arranged thereon is also relatively small.

[0034] In this embodiment, the cylindrical battery cover assembly is an overall circular structure to be suitable for cylindrical batteries, and the cylindrical battery cover assembly is arranged on the side of the battery cell where the positive electrode tab and the negative electrode tab are provided to facilitate subsequent tab connection operations.

[0035] The cylindrical battery cover assembly includes a pole and a current collector 1, the pole is mainly used to lead out the battery voltage, and the current collector 1 includes a pole lug connection area and a pole lug connection area, the pole lug connection area is connected to the pole lug, and the pole lug connection area is connected to the pole. Of course, the cylindrical battery cover assembly also includes other structures that existing cylindrical battery cover assemblies have, such as explosion-proof valves, etc., which are not involved in this embodiment and are not described here.

[0036] In this embodiment, the thickness of the tab connection area is different from the thickness of the pole connection area, that is, the thickness of the current collector 1 as a whole is not uniform. Specifically, the ratio of the thickness b of the tab connection area to the thickness a of the pole connection area satisfies 0.2≤b / a<1. Within the above ratio range, the thickness of the tab connection area will not be too thick or too thin, which can ensure the heat dissipation performance of the tab connection area, balance the heat dissipation capacity of the current collector, and ensure the current flow capacity of the tab connection area, thereby meeting the battery performance requirements and improving the battery life.

[0037] In this embodiment, the thickness b of the pole lug connection area ranges from 0.1mm to 1mm, for example, the thickness b of the pole lug connection area is 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, etc., and the thickness a of the pole connection area ranges from 0.2mm to 2mm, for example, the thickness a of the pole connection area is 0.2mm, 0.5mm, 0.7mm, 0.8mm, 1mm, 1.2mm, 1.3mm, 1.5mm, 1.8mm, 2mm, etc. The ratio of the thickness b of the pole lug connection area to the thickness a of the pole connection area can be 0.2, 0.4, 0.5, 0.8, 0.95, etc.

[0038] Furthermore, the current collector 1 includes a positive current collector 2 and a negative current collector 3, the positive current collector 2 includes a positive electrode tab connection area 201 and a positive electrode post connection area 202, the negative current collector 3 includes a negative electrode tab connection area 301 and a negative electrode post connection area 302, the positive electrode post connection area 202 or the negative electrode post connection area 302 is arranged between the positive electrode tab connection area 201 and the negative electrode tab connection area 301, and at this time the ratio of thickness b to thickness a satisfies 0.25≤b / a≤0.9.

[0039] The current collector 1 includes a positive current collector 2 and a negative current collector 3, which can be integrated into one body and insulated from each other. The positive current collector 2 and the negative current collector 3 are arranged on one side of the battery cell where the tab is arranged.

[0040] Among them, the positive current collector 2 is also called the positive current collector plate, and the negative current collector 3 is also called the negative current collector plate. The positive current collector 2 is suitable for connecting with the positive pole ear and the positive pole column of the battery, and the negative current collector 3 is suitable for connecting with the negative pole ear and the negative pole column of the battery. Usually, the positive current collector 1 is connected to the positive pole ear and the positive pole column by welding, and similarly, the negative current collector 3 is connected to the negative pole ear and the negative pole column by welding. The positive current collector 1 is made of aluminum, and the negative current collector 3 is made of copper. It can be understood that the positive current collector 1 and the negative current collector 3 are both plate-like structures with a certain thickness as a whole, so as to be arranged in the battery.

[0041] The positive electrode current collector 2 includes a positive electrode tab connection area 201 and a positive electrode post connection area 202, and the positive electrode tab connection area 201 and the positive electrode post connection area 202 are connected to each other. Figure 3-Figure 4 As shown, in this embodiment, the positive electrode current collector 2 is a disc-shaped structure as a whole, the middle part of the positive electrode current collector 2 is hollowed out, the positive electrode pole connection area 202 is an outer peripheral ring structure, and the positive electrode pole connection area 201 is inside the positive electrode pole connection area 202. When the positive electrode current collector 2 is placed horizontally, the horizontal position of the positive electrode pole connection area 201 is lower than the horizontal position of the positive electrode pole connection area 202, that is, the positive electrode pole connection area 201 is concave relative to the positive electrode pole connection area 202. The poles include a positive pole 4 and a negative pole 5, the positive pole ear connection area 201 is connected to the positive pole ear, and the positive pole column connection area 202 is connected to the positive pole 4, and the above connection method is usually welding.

[0042] Optionally, the positive electrode tab connection area 201 and the positive electrode post connection area 202 are integrally formed.

[0043] The negative electrode current collector 3 includes a negative electrode tab connection area 301 and a negative electrode post connection area 302, and the negative electrode tab connection area 301 and the negative electrode post connection area 302 are connected to each other. Specifically, the negative electrode post connection area 302 is arranged on the inner side of the negative electrode tab connection area 301. When the negative electrode current collector 3 is placed horizontally, the negative electrode post connection area 302 protrudes upward from the negative electrode tab connection area 301 to facilitate connection with the negative electrode post. The negative electrode tab connection area 301 is connected to the negative electrode tab, and the negative electrode post connection area 302 is connected to the negative electrode post 5. The above connection method is usually welding.

[0044] Optionally, the negative electrode tab connection area 301 and the negative electrode post connection area 302 are integrally formed.

[0045] The positive pole column connection area 202 or the negative pole column connection area 302 is arranged between the positive pole tab connection area 201 and the negative pole tab connection area 301. Cylindrical batteries are divided into steel shell cylindrical batteries and aluminum shell cylindrical batteries. In steel shell cylindrical batteries, the negative pole column connection area 302 is arranged between the positive pole tab connection area 201 and the negative pole tab connection area 301. In aluminum shell cylindrical batteries, the positive pole column connection area 202 is arranged between the positive pole tab connection area 201 and the negative pole tab connection area 301. Figure 1 and Figure 4 As shown, in this embodiment, the cylindrical battery cover plate assembly is applied to a steel shell cylindrical battery, that is, the negative electrode column connection area 302 is arranged between the positive electrode tab connection area 201 and the negative electrode tab connection area 301.

[0046] At this time, the ratio of thickness b to thickness a satisfies 0.25≤b / a≤0.9. In this embodiment, the negative pole column connection area 302 is arranged between the positive pole tab connection area 201 and the negative pole tab connection area 301. Since the pole column connection area (negative pole column connection area 302) is provided with pole tab connection areas (positive pole tab connection area 201 and negative pole tab connection area 301) on both sides, the total heat dissipation capacity of the pole tab connection area can be improved to ensure balanced heat dissipation of the pole tab connection areas on both sides of the pole column connection area. Therefore, the lower limit of the ratio of the thickness b of the pole tab connection area to the thickness a of the pole column connection area can be larger, so that the thickness of the pole tab connection area is thicker and a better current flow effect is achieved. For example, the ratio of thickness b to thickness a can be 0.25, 0.4, 0.7, 0.9, etc.

[0047] Furthermore, the positive electrode tab connection area 201 and the negative electrode tab connection area 301 include a fan-shaped structure, and the positive electrode tab connection area 201 and the negative electrode tab connection area 301 are arranged around the positive electrode column connection area 202 or the negative electrode column connection area 302, and the sum of the central angle of the positive electrode tab connection area 201 and the central angle of the negative electrode tab connection area 301 is in the range of 150°~350°, at this time, the ratio of thickness b to thickness a satisfies 0.28≤b / a≤0.85, and the central angle range of the positive electrode tab connection area 201 and the central angle range of the negative electrode tab connection area 301 are both 75°~175°.

[0048] The positive pole tab connection area 201 and the negative pole tab connection area 301 include a fan-shaped structure, and the positive pole tab connection area 201 and the negative pole tab connection area 301 are arranged around the positive pole column connection area 202 or the negative pole column connection area 302. In the present embodiment, the positive pole tab connection area 201 and the negative pole tab connection area 301 are arranged around the negative pole column connection area 302, and the negative pole column connection area 302 is located at the center of the positive pole tab connection area 201 and the negative pole tab connection area 301.

[0049] The sum of the central angle of the positive electrode tab connection area 201 and the central angle of the negative electrode tab connection area 301 is in the range of 150° to 350°, so that the setting area of ​​the positive electrode tab connection area 201 and the negative electrode tab connection area 301 is large enough to ensure the flow capacity of the positive electrode tab connection area 201 and the negative electrode tab connection area 301. For example, the sum of the central angle of the positive electrode tab connection area 201 and the central angle of the negative electrode tab connection area 301 can be 150°, 210°, 300°, 350°, etc.

[0050] At this time, the ratio of thickness b to thickness a satisfies 0.28≤b / a≤0.85. In this embodiment, the area of ​​the positive pole tab connection area 201 and the negative pole tab connection area 301 is large enough to improve the total heat dissipation capacity of the pole tab connection area and ensure the balanced heat dissipation of the pole tab connection areas on both sides of the pole connection area. Therefore, the lower limit of the ratio of the thickness b of the pole tab connection area to the thickness a of the pole connection area can be larger, so that the thickness of the pole tab connection area is thicker and a better current flow effect is achieved. For example, the ratio of thickness b to thickness a can be 0.28, 0.3, 0.6, 0.85, etc.

[0051] In this embodiment, the center angle of the positive electrode tab connection area 201 ranges from 75° to 175°, for example, the center angle of the positive electrode tab connection area 201 can be 75°, 82°, 120°, 175°, etc. The center angle of the negative electrode tab connection area 301 also ranges from 75° to 175°, for example, the center angle of the negative electrode tab connection area 301 can be 75°, 95°, 110°, 175°, etc. However, the center angle of the positive electrode tab connection area 201 is not necessarily equal to the center angle of the negative electrode tab connection area 301, and the two can be equal or unequal.

[0052] Furthermore, the material of the pole column connection area between the positive pole tab connection area 201 and the negative pole tab connection area 301 is copper, the ratio of the thickness of the positive pole tab connection area 201 to the thickness of the positive pole column connection area 202 is in the range of 0.3~0.8, and the ratio of the thickness of the negative pole tab connection area 301 to the thickness of the negative pole column connection area 302 is also in the range of 0.3~0.8.

[0053] The material of the pole column connection area between the positive pole tab connection area 201 and the negative pole tab connection area 301 is copper, that is, the pole column connection area between the positive pole tab connection area 201 and the negative pole tab connection area 301 is the negative pole column connection area 302. At this time, the ratio of the thickness of the positive pole tab connection area 201 to the thickness of the positive pole column connection area 202 is in the range of 0.3 to 0.8. For example, the ratio of the thickness of the positive pole tab connection area 201 to the thickness of the positive pole column connection area 202 is 0.3, 0.5, 0.7, 0.8, etc., and the ratio of the thickness of the negative pole tab connection area 301 to the thickness of the negative pole column connection area 302 is also in the range of 0.3 to 0.8. For example, the ratio of the thickness of the negative pole tab connection area 301 to the thickness of the negative pole column connection area 302 is 0.3, 0.65, 0.75, 0.8, etc. Since copper has better heat dissipation performance, the lower limit of the ratio of the thickness b of the pole connection area to the thickness a of the pole connection area with the same polarity can be larger, so that the thickness of the pole connection area is thicker, so as to achieve good heat dissipation and current capacity at the same time.

[0054] Furthermore, the positive electrode current collector 2 and the negative electrode current collector 3 are connected via the insulating member 8 , and the ratio of the thickness of the negative electrode tab connection area 301 to the thickness of the positive electrode tab connection area 201 is in the range of 0.5-1.

[0055] like Figure 3 and Figure 4 As shown, in this embodiment, the current collector 1 is an integrated integral structure, that is, the positive current collector 2 and the negative current collector 3 are integrated into one, and the positive current collector 2 and the negative current collector 3 are insulated. Specifically, the positive current collector 2 and the negative current collector 3 are connected to form an integral structure through the insulating member 8, that is, the insulating member 8 is connected to the positive current collector 2 and the negative current collector 3 at the same time, so that the positive current collector 2, the negative current collector 3 and the insulating member 8 form an integral structure, and the integral structure is the current collector 1.

[0056] The insulating member 8 is made of insulating materials such as resin and plastic, and the positive current collector 2, the negative current collector 3 and the insulating member 8 can be connected together by hot melting, injection molding, etc. Of course, after the positive current collector 2, the negative current collector 3 and the insulating member 8 are connected, the positive current collector 2 and the negative current collector 3 are kept insulated. In addition, the positive current collector 2 and the negative current collector 3 are arranged on the side of the battery cell where the pole ear is arranged, so as to facilitate the subsequent connection of the pole ear.

[0057] The insulating member 8 is a circular structure as a whole, and its outer peripheral annular structure is suitable for cooperating with the positive electrode pole connection area 202. The middle part of the insulating member 8 has two hollow parts, namely a first hollow part 801 and a second hollow part 802, wherein the first hollow part 801 corresponds to the negative electrode current collector 3, and the negative electrode current collector 3 is arranged at the first hollow part 801, and the second hollow part 802 corresponds to the positive electrode tab connection area 201, and the positive electrode tab connection area 201 is arranged at the second hollow part 802.

[0058] At this time, the ratio of the thickness of the negative electrode tab connection area 301 to the thickness of the positive electrode tab connection area 201 is in the range of 0.5 to 1. When the positive electrode current collector 2 and the negative electrode current collector 3 are connected through the insulating member 8, since the position where the insulating member 8 is connected to the positive electrode current collector 2 and the negative electrode current collector 3 is relatively close to the tab connection area, the ratio of the thickness of the positive electrode tab connection area 201 to the negative electrode tab connection area 301 needs to be within the above range to prevent the thickness difference between the positive electrode tab connection area 201 and the negative electrode tab connection area 301 from being too large, which makes it difficult to fix the insulating member 8, and then causes the entire current collector 1 to tilt.

[0059] For example, the ratio of the thickness of the negative electrode tab connection area 301 to the thickness of the positive electrode tab connection area 201 can be 0.5, 0.7, 1, etc. When the thickness ratio of the positive electrode tab connection area 201 to the negative electrode tab connection area 301 is within the above range, the difference in thickness between the positive electrode tab connection area 201 and the negative electrode tab connection area 301 will not be too large, so that the insulating member 8 can be easily connected and fixed to the positive electrode current collector 2 and the negative electrode current collector 3, and the entire current collector 1 will not be tilted.

[0060] In order to facilitate molding, the thickness of the pole connection area of ​​the current collector 1 is uniform, and the thickness of the pole lug connection area is also uniform. In the pole connection area, a part of it will be welded to the pole, while the other part will not be welded to the pole. The part not welded to the pole is the effective area of ​​the pole connection area. Similarly, in the pole lug welding area, a part of it will be welded to the pole lug, while the other part will not be welded to the pole lug. The part not welded to the pole lug is the effective area of ​​the pole lug connection area. During the measurement process, the thickness of the effective area of ​​the pole connection area can represent the thickness of the entire pole connection area. Similarly, the thickness of the effective area of ​​the pole lug connection area can represent the thickness of the entire pole lug connection area.

[0061] Furthermore, the positive electrode tab connection area 201 and the negative electrode tab connection area 301 are arranged around the positive electrode column connection area 202 or the negative electrode column connection area 302, and the ratio of the central angle of the positive electrode tab connection area 201 to the central angle of the negative electrode tab connection area 301 is in the range of 0.5~1, and at this time, the ratio of the thickness b to the thickness a satisfies 0.6≤b / a≤0.8.

[0062] like Figure 1 , 3 4, in this embodiment, the cylindrical battery cover plate assembly is applied to the steel shell cylindrical battery, so the positive pole tab connection area 201 and the negative pole tab connection area 301 are arranged around the negative pole column connection area 302, and the positive pole tab connection area 201 and the negative pole tab connection area 301 include a fan-shaped structure, and the positive pole tab connection area 201 includes a fan-shaped structure, which is connected to the positive pole tab, and has a connecting plate 203 protruding outward at both sides of the fan-shaped structure, and the connecting plate 203 is used to connect the insulating member 8. The ratio of the central angle of the positive pole tab connection area 201 to the central angle of the negative pole tab connection area 301 ranges from 0.5 to 1, for example, the ratio of the central angle of the positive pole tab connection area 201 to the central angle of the negative pole tab connection area 301 can be 0.5, 0.7, 0.9, 1, etc.

[0063] At this time, the ratio of thickness b to thickness a satisfies 0.6≤b / a≤0.8. Since the ratio of the central angle of the positive electrode tab connection area 201 to the central angle of the negative electrode tab connection area 301 is within the above range, the central angle of the positive electrode tab connection area 201 is close to the central angle of the negative electrode tab connection area 301. At this time, the lower limit value of the ratio range of thickness b to thickness a can be set larger to make the thickness of the tab connection area thicker and achieve better current flow effect.

[0064] Furthermore, a protrusion 7 is provided in the pole connection area, and at this time, the ratio of the thickness b to the thickness a satisfies 0.2≤b / a≤0.8.

[0065] A protrusion 7 is provided in the pole connection area. In the present embodiment, a protrusion 7 is provided in the negative pole connection area 302, and the protrusion 7 extends and protrudes toward the negative pole 5. At this time, the ratio of thickness b to thickness a satisfies 0.2≤b / a≤0.8. The cylindrical battery cover assembly also includes a cover body. When the protrusion 7 is provided in the pole connection area, the contact surface between the pole connection area and the cover body is larger and the heat dissipation is better. Therefore, the thickness dimension of the pole connection area can be thicker, that is, the upper limit value of the ratio range of thickness b to thickness a can be smaller. For example, the ratio of thickness b to thickness a can be 0.2, 0.42, 0.68, 0.8, etc.

[0066] Furthermore, the pole has a groove 6 arranged toward the current collector 1, the protrusion 7 is at least partially placed in the groove 6, the protrusion 7 is connected to the pole, and a flange 10 is provided on one side edge of the groove 6 close to the current collector 1, the flange 10 is arranged between the current collector 1 and the cover body, the overlapping area of ​​the flange 10 and the pole ear connection area is m, the area of ​​the pole ear connection area is d, and the ratio of area m to area d satisfies 0.05≤m / d≤0.4.

[0067] like Figure 1-Figure 2 As shown, the cylindrical battery cover assembly also includes a cover body, which is a disc-shaped structure as a whole, and the diameter of the cover body matches the current collector 1. The cover body is the positive pole 4, and a through hole is formed at the center of the cover body, and a part of the negative pole 5 is suitable for passing through the through hole, so that the negative pole 5 and the positive pole 4 are assembled and connected. After the negative pole 5 and the positive pole 4 are assembled, the negative pole 5 and the positive pole 4 are insulated, such as an insulating ring can be set at the connection position between the negative pole 5 and the positive pole 4.

[0068] After the negative electrode column 5 and the positive electrode column 4 are assembled, one side of the negative electrode column 5 faces the current collector 1. Figure 1 Taking the perspective shown as an example, the bottom of the negative electrode post 5 faces the current collector 1. The side of the negative electrode post 5 facing the current collector 1 cooperates with the negative electrode post connection area 302.

[0069] The pole has a groove 6 arranged toward the current collector 1. Specifically, the negative pole 5 has a groove 6 arranged toward the current collector 1, that is, the opening of the groove 6 faces the current collector 1, and the protrusion 7 protrudes toward the negative pole 5. The size and shape of the groove 6 match the size and shape of the protrusion 7. The protrusion 7 is at least partially inserted into the groove 6 and placed in the groove 6. In this embodiment, the cross-sections of the groove 6 and the protrusion 7 perpendicular to the axial direction are both circular, and the axial direction of the groove 6 and the protrusion 7 is Figure 1 The inner wall of the groove 6 and the outer wall of the protrusion 7 are clearance-matched. In this embodiment, the groove 6 and the protrusion 7 are clearance-matched in the circumferential direction so that the protrusion 7 can be smoothly and conveniently inserted into the groove 6, which is convenient for the subsequent welding of the protrusion 7 and the negative electrode column 5.

[0070] A flange 10 is provided on one side edge of the groove 6 close to the current collector 1, and the flange 10 is provided between the current collector 1 and the cover body to improve the reliability of the structural connection. The flange 10 is provided between the current collector 1 and the cover body, and the overlapping area of ​​the flange 10 and the pole ear connection area is m, the area of ​​the pole ear connection area is d, and the ratio of area m to area d satisfies 0.05≤m / d≤0.4. In this embodiment, the overlapping area of ​​the flange 10 and the negative pole ear connection area 301 is m, the area of ​​the negative pole ear connection area 301 is d, and the ratio of area m to area d satisfies 0.05≤m / d≤0.4, for example, the ratio of area m to area d is 0.05, 0.09, 0.2, 0.4, etc. The flange 10 has a certain overlapping area with the pole ear connection area, which can improve the heat dissipation performance, but the overlapping area should not be too large, otherwise there is a risk of insulation failure. The ratio of the area m to the area d being within the above range is beneficial to improving the heat dissipation performance and ensuring the insulation performance.

[0071] This embodiment also provides a battery, including the cylindrical battery cover assembly and a battery cell as described above, the battery cell including a pole ear, the pole ear is connected to the pole ear connection area of ​​the current collector in the cover assembly, the positive projection area of ​​the pole ear on the current collector 1 is c, the area of ​​the pole ear connection area is d, and the ratio of area c to area d satisfies 0.5≤c / d<1.

[0072] like Figure 5 As shown, the battery of this embodiment is a battery with positive and negative electrodes led out on the same side, specifically a cylindrical battery, which has a battery housing 9, in which a battery cell and a cover assembly and other structures are arranged, and the battery cell includes a positive electrode tab and a negative electrode tab, which are arranged on the same side of the battery cell to achieve the same-side lead-out of the positive and negative electrodes. Of course, the battery of this embodiment also has other structures and components that existing batteries have, which will not be repeated here.

[0073] During the battery manufacturing process, the positive electrode tab and the positive electrode column 4 are connected to the positive electrode current collector 2, and the positive electrode current collector 2 is subsequently connected to the battery casing 9, and the negative electrode tab and the negative electrode column 5 are connected to the negative electrode current collector 3.

[0074] The positive projection area of ​​the tab of the battery cell on the current collector 1 is c, the area of ​​the tab connection area is d, and the ratio of area c to area d satisfies 0.5≤c / d<1. For example, the ratio of area c to area d can be 0.5, 0.7, 0.95, etc. When the ratio of area c to area d is within the above range, sufficient heat dissipation space can be reserved and the current capacity of the tab connection area can be guaranteed.

[0075] Furthermore, a plurality of pole ears are provided, and the plurality of pole ears are arranged at intervals along the circumferential direction, and the interval between adjacent pole ears ranges from 0.05 mm to 1 mm.

[0076] In this embodiment, multiple tabs are provided, that is, multiple positive tabs are provided, and multiple negative tabs are also provided, and multiple tabs are arranged at intervals along the circumferential direction. Of course, the positive tabs and the negative tabs must maintain a certain distance to ensure insulation. The spacing between adjacent tabs ranges from 0.05mm to 1mm. For example, the spacing between adjacent tabs can be 0.05mm, 0.068mm, 0.08mm, 1mm, etc. When the spacing between adjacent tabs is within the above range, heat dissipation space can be reserved to improve the heat dissipation effect.

[0077] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A cylindrical battery cover assembly, characterized in that: Applied to a battery, the battery comprises a battery cell, the battery cell comprises a tab, the tab comprises a positive tab and a negative tab, the positive tab and the negative tab are arranged on the same side of the battery cell; the cylindrical battery cover assembly comprises: Pole; A current collector (1), comprising a pole lug connection area and a pole post connection area, wherein the pole lug connection area is connected to the pole lug, and the pole post connection area is connected to the pole post, so as to realize electrical connection between the pole lug and the pole post, wherein the thickness of the pole post connection area is a, and the thickness of the pole lug connection area is b, and the ratio of the thickness b to the thickness a satisfies 0.2≤b / a<1; The current collector (1) comprises a positive current collector (2) and a negative current collector (3), the positive current collector (2) comprises a positive pole tab connection area (201) and a positive pole column connection area (202), the negative current collector (3) comprises a negative pole tab connection area (301) and a negative pole column connection area (302), the positive pole column connection area (202) or the negative pole column connection area (302) is arranged between the positive pole tab connection area (201) and the negative pole tab connection area (301), and at this time, the ratio of the thickness b to the thickness a satisfies 0.25≤b / a≤0.9; The positive electrode tab connection area (201) and the negative electrode tab connection area (301) are arranged around the positive electrode column connection area (202) or the negative electrode column connection area (302).

2. The cylindrical battery cover assembly according to claim 1, characterized in that: The positive electrode tab connection area (201) and the negative electrode tab connection area (301) comprise a fan-shaped structure, and the sum of the central angle of the positive electrode tab connection area (201) and the central angle of the negative electrode tab connection area (301) is in the range of 150° to 350°, at which time the ratio of the thickness b to the thickness a satisfies 0.28≤b / a≤0.85, and the central angle range of the positive electrode tab connection area (201) and the central angle range of the negative electrode tab connection area (301) are both 75° to 175°.

3. The cylindrical battery cover assembly according to claim 1, characterized in that: The material of the pole column connection area located between the positive pole tab connection area (201) and the negative pole tab connection area (301) is copper, the ratio of the thickness of the positive pole tab connection area (201) to the thickness of the positive pole column connection area (202) is in the range of 0.3 to 0.8, and the ratio of the thickness of the negative pole tab connection area (301) to the thickness of the negative pole column connection area (302) is also in the range of 0.3 to 0.

8.

4. The cylindrical battery cover assembly according to claim 1, characterized in that: The positive electrode current collector (2) and the negative electrode current collector (3) are connected via an insulating member (8), and the ratio of the thickness of the negative electrode tab connection area (301) to the thickness of the positive electrode tab connection area (201) is in the range of 0.5 to 1.

5. The cylindrical battery cover assembly according to claim 4, characterized in that: The positive electrode tab connection area (201) and the negative electrode tab connection area (301) are arranged around the positive electrode column connection area (202) or the negative electrode column connection area (302), and the ratio of the center angle of the positive electrode tab connection area (201) to the center angle of the negative electrode tab connection area (301) is in the range of 0.5 to 1, and at this time, the ratio of the thickness b to the thickness a satisfies 0.6≤b / a≤0.

8.

6. The cylindrical battery cover assembly according to claim 1, characterized in that: The pole connection area is provided with a protruding portion (7), and at this time, the ratio of the thickness b to the thickness a satisfies 0.2≤b / a≤0.

8.

7. The cylindrical battery cover assembly according to claim 6, characterized in that: The cylindrical battery cover plate assembly further comprises a cover plate body, the pole having a groove (6) arranged towards the current collector (1), the protrusion (7) being at least partially disposed in the groove (6), the protrusion (7) being connected to the pole, a flange (10) being disposed on one side edge of the groove (6) close to the current collector (1), the flange (10) being disposed between the current collector (1) and the cover plate body, the overlapping area between the flange (10) and the pole lug connection region being m, the area of ​​the pole lug connection region being d, and the ratio of the area m to the area d satisfying 0.05≤m / d≤0.

4.

8. A battery, characterized in that: The invention comprises a cylindrical battery cover assembly and a battery cell as claimed in any one of claims 1 to 7, wherein the battery cell comprises a pole lug, the pole lug is connected to a pole lug connection area of ​​a current collector (1) in the cylindrical battery cover assembly, the positive projection area of ​​the pole lug on the current collector is c, the area of ​​the pole lug connection area is d, and the ratio of area c to area d satisfies 0.5≤c / d<1.

9. The battery according to claim 8, characterized in that There are multiple pole ears, and the multiple pole ears are arranged at intervals along the circumferential direction. The interval between adjacent pole ears ranges from 0.05mm to 1mm.

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