Cylindrical battery cover assembly and battery

Abstract

This invention relates to the field of new energy battery technology and discloses a cylindrical battery cover assembly and a battery. The cylindrical battery cover assembly has good heat dissipation performance in the tab connection area, reducing heat concentration problems, extending battery life, and ensuring the current carrying capacity of the tab connection area, thus improving battery performance. The cylindrical battery cover assembly of this invention is applied to a battery, which includes a cell, a tab, a positive tab, and a negative tab, both located on the same side of the cell. The cylindrical battery cover assembly includes a terminal post and a current collector, the current collector including a tab connection area and a terminal post connection area. The tab connection area is connected to the tab, and the terminal post connection area is connected to the terminal post to achieve electrical connection between the tab and the terminal post. The thickness of the terminal post connection area is 'a', and the thickness of the tab connection area is 'b', with the ratio of thickness b to thickness a satisfying 0.2 ≤ b / a < 1.

Description

[0001] This application is a divisional application of the patent application filed on October 8, 2024, with application number 2024113909393 and invention title "Cylindrical Battery Cover Assembly and Battery". Technical Field

[0002] This invention relates to the field of new energy battery technology, specifically to a cylindrical battery cover assembly and battery. Background Technology

[0003] Cylindrical batteries are widely used due to their high capacity, long cycle life, and wide operating temperature range. The positive and negative electrodes of a cylindrical battery are led out on the same side, and the current collector in its cover assembly needs to be welded to the tabs and terminals. During tab welding and battery operation, significant heat is generated at the tab-current collector connection point. If the current collector is too thick, heat will concentrate in the tab connection area, resulting in poor heat dissipation. Conversely, if the current collector is too thin, it will affect the current carrying capacity of the tab connection area, impacting battery performance. Therefore, existing current collectors do not meet the requirements. Summary of the Invention

[0004] In view of this, the present invention provides a cylindrical battery cover assembly and a battery to solve the problems of poor heat dissipation performance when the current collector of the existing battery is too thin, and poor current carrying capacity when the current collector is too thick.

[0005] In a first aspect, the present invention provides a cylindrical battery cover assembly applied to a battery, the battery including a cell, the cell including tabs, the tabs including a positive tab and a negative tab, the positive tab and the negative tab being disposed on the same side of the cell; the cylindrical battery cover assembly includes:

[0006] pole;

[0007] The current collector includes a tab connection area and a post connection area. The tab connection area is connected to the tab, and the post connection area is connected to the post to realize the electrical connection between the tab and the post. The thickness of the post connection area is a, and the thickness of the tab connection area is b. The ratio of thickness b to thickness a satisfies 0.2≤b / a<1.

[0008] Beneficial Effects: The cover plate assembly of the present invention includes a pole and a current collector. The current collector includes a tab connection area and a pole connection area. The tab connection area is connected to a tab, and the pole connection area is connected to a pole. 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. If the ratio of the thickness b of the tab connection area to the thickness a of the pole connection area is higher than the above range, the thickness of the tab connection area is too thick, which will lead to poor heat dissipation performance of the tab connection area. Conversely, if the ratio of the thickness b of the tab connection area to the thickness a of the pole connection area is lower than the above range, the thickness of the tab connection area is too thin, which will affect the current carrying capacity of the tab connection area.

[0009] In this application, the thickness of the current collector is not uniform; rather, the thickness of the tab connection area is thinner than that of the terminal connection area. Due to the greater distance between the tab connection area and the cover plate body in the cover plate assembly, the heat dissipation of the tab connection area is poor. When the ratio of the thickness b of the tab connection area to the thickness a of the terminal connection area satisfies 0.2≤b / a<1, the heat dissipation capacity of the current collector can be balanced, resulting in better heat dissipation performance of the tab connection area. During battery operation, the large amount of heat generated by the tab can be dissipated through the tab connection area of ​​the current collector, cooling the tab and the tab connection area, reducing heat concentration, extending battery life, and ensuring the current carrying capacity of the tab connection area, thereby improving battery performance.

[0010] Secondly, the present invention provides a battery, including a cylindrical battery cover assembly as described above and a battery cell. The battery cell includes a tab, which is connected to the tab connection area of ​​a current collector in the cover assembly. The orthographic projection area of ​​the tab on the current collector is c, and the area of ​​the tab connection area is d. The ratio of area c to area d satisfies 0.5 ≤ c / d < 1.

[0011] Since 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 elaborated here. Attached Figure Description

[0012] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0013] Figure 1 This is an exploded view of the cover plate assembly (hidden part structure) of the present invention;

[0014] Figure 2 This is a cross-sectional view of the cover plate assembly of the present invention;

[0015] Figure 3 This is a schematic diagram of the current collector in the cover plate assembly of the present invention;

[0016] Figure 4 This is an exploded view of the current collector in the cover plate assembly of the present invention;

[0017] Figure 5 This is a schematic diagram of the battery of the present invention.

[0018] Explanation of reference numerals in the attached figures:

[0019] 1. Current collector;

[0020] 2. Positive current collector; 201. Positive electrode tab connection area; 202. Positive electrode post connection area; 203. Connecting plate;

[0021] 3. Negative current collector; 301. Negative electrode tab connection area; 302. Negative electrode post connection area;

[0022] 4. Positive terminal post (cover plate body);

[0023] 5. Negative terminal;

[0024] 6. Groove;

[0025] 7. Protrusion;

[0026] 8. Insulating component; 801. First hollowed-out section; 802. Second hollowed-out section;

[0027] 9. Battery casing;

[0028] 10. Flip the edge. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] The following is combined Figures 1-5 This describes embodiments of the cylindrical battery cover assembly and battery of the present invention.

[0031] According to an embodiment of the present invention, in one aspect, a cylindrical battery cover assembly is provided, applied to a battery, the battery including a cell, the cell including tabs, the tabs including a positive tab and a negative tab, the positive tab and the negative tab being disposed on the same side of the cell; the cylindrical battery cover assembly includes: a terminal post and a current collector 1, the current collector 1 including a tab connection area and a terminal post connection area, the tab connection area being connected to the tab, and the terminal post connection area being connected to the terminal post to realize the electrical connection between the tab and the terminal post, the thickness of the terminal post connection area being a, the thickness of the tab connection area being b, and the ratio of thickness b to thickness a satisfying 0.2≤b / a<1.

[0032] This cover plate assembly includes a terminal post and a current collector. The current collector 1 includes a tab connection area and a terminal post connection area. The tab connection area is connected to a tab, and the terminal post connection area is connected to a terminal post. The ratio of the thickness b of the tab connection area to the thickness a of the terminal post connection area satisfies 0.2 ≤ b / a < 1. If the ratio of the thickness b of the tab connection area to the thickness a of the terminal post connection area is higher than the above range, the thickness of the tab connection area is too thick, which will lead to poor heat dissipation performance of the tab connection area. Conversely, if the ratio of the thickness b of the tab connection area to the thickness a of the terminal post connection area is lower than the above range, the thickness of the tab connection area is too thin, which will affect the current carrying capacity of the tab connection area.

[0033] In this application, the thickness of the current collector 1 is not uniform; rather, the thickness of the tab connection area is thinner than that of the terminal connection area. Because the distance between the tab connection area and the cover plate body in the cover plate assembly is relatively large, the heat dissipation of the tab connection area is poor. When the ratio of the thickness b of the tab connection area to the thickness a of the terminal connection area satisfies 0.2≤b / a<1, the heat dissipation capacity of the current collector can be balanced, resulting in better heat dissipation performance of the tab connection area. During battery operation, the large amount of heat generated by the tab can be dissipated through the tab connection area of ​​the current collector, cooling the tab and the tab connection area, reducing the problem of heat concentration, extending battery life, and ensuring the current carrying capacity of the tab connection area, thereby improving battery performance.

[0034] The cylindrical battery cover assembly of this embodiment is applied to a battery in which the positive and negative electrodes are led out on the same side. Specifically, this battery is a cylindrical battery, which includes a cell, a tab, and positive and negative tabs. The positive and negative tabs are located on the same side of the cell to achieve simultaneous lead-out of the positive and negative electrodes. This cylindrical battery with simultaneous lead-out of the positive and negative electrodes has a compact structure and small volume, and the current collector 1 and other structures mounted on it are also relatively small in size.

[0035] In this embodiment, the cylindrical battery cover assembly has an overall circular structure to be suitable for cylindrical batteries, and the cylindrical battery cover assembly is disposed on the side of the battery cell where the positive and negative electrode tabs are provided, so as to facilitate the subsequent tab connection operation.

[0036] The cylindrical battery cover assembly includes terminals and a current collector 1. The terminals are mainly used for drawing out the battery voltage. The current collector 1 includes a tab connection area and a terminal connection area. The tab connection area is connected to the tab, and the terminal connection area is connected to the terminal. Of course, the cylindrical battery cover assembly also includes other structures that are present in existing cylindrical battery cover assemblies, such as explosion-proof valves, etc., which are not involved in this embodiment and will not be described in detail here.

[0037] In this embodiment, the thickness of the tab connection area and the thickness of the terminal connection area are different, meaning the overall thickness of the current collector 1 is not uniform. Specifically, the ratio of the thickness b of the tab connection area to the thickness a of the terminal connection area satisfies 0.2 ≤ b / a < 1. Within the above ratio range, the thickness of the tab connection area is neither too thick nor too thin, ensuring both the heat dissipation performance of the tab connection area and the heat dissipation capacity of the current collector, while also ensuring the current carrying capacity of the tab connection area, thereby meeting the battery performance requirements and improving battery lifespan.

[0038] In this embodiment, the thickness b of the tab connection area ranges from 0.1mm to 1mm, for example, the thickness b of the tab 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., and the ratio of the thickness b of the tab connection area to the thickness a of the pole connection area can be 0.2, 0.4, 0.5, 0.8, 0.95, etc.

[0039] 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 disposed between the positive electrode tab connection area 201 and the negative electrode tab connection area 301. At this time, the ratio of thickness b to thickness a satisfies 0.25≤b / a≤0.9.

[0040] The current collector 1 includes a positive current collector 2 and a negative current collector 3. The positive current collector 2 and the negative current collector 3 can be integrated into one unit, and the positive current collector 2 and the negative current collector 3 are insulated from each other. The positive current collector 2 and the negative current collector 3 are disposed on the side of the battery cell where the tabs are provided.

[0041] 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 connection with the positive electrode tab and positive electrode post of the battery, and the negative current collector 3 is suitable for connection with the negative electrode tab and negative electrode post of the battery. Usually, the positive current collector 1 is connected to the positive electrode tab and positive electrode post by welding, and similarly, the negative current collector 3 is connected to the negative electrode tab and negative electrode post 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 both the positive current collector 1 and the negative current collector 3 are plate-like structures with a certain thickness to facilitate their installation inside the battery.

[0042] The positive current collector 2 includes a positive electrode tab connection region 201 and a positive electrode post connection region 202, which are interconnected. Figures 3-4 As shown, in this embodiment, the positive current collector 2 is generally a disc-shaped structure with a hollowed-out central portion. The positive electrode post connection area 202 has an outer ring structure, and the positive electrode tab connection area 201 is located inside the positive electrode post connection area 202. When the positive current collector 2 is placed horizontally, the horizontal position of the positive electrode tab connection area 201 is lower than the horizontal position of the positive electrode post connection area 202, that is, the positive electrode tab connection area 201 is concave downward relative to the positive electrode post connection area 202. The electrode post includes a positive electrode post 4 and a negative electrode post 5. The positive electrode tab connection area 201 is connected to the positive electrode tab, and the positive electrode post connection area 202 is connected to the positive electrode post 4. The connection method is usually welding.

[0043] Optionally, the positive electrode tab connection area 201 and the positive electrode post connection area 202 are integrally formed.

[0044] The negative current collector 3 includes a negative electrode tab connection area 301 and a negative electrode post connection area 302, which are interconnected. Specifically, the negative electrode post connection area 302 is located inside the negative electrode tab connection area 301. When the negative 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 connection method is typically welding.

[0045] Optionally, the negative electrode tab connection area 301 and the negative electrode post connection area 302 are integrally formed.

[0046] A positive electrode connection region 202 or a negative electrode connection region 302 is disposed between a positive electrode tab connection region 201 and a negative electrode tab connection region 301. Cylindrical batteries are divided into steel-cased cylindrical batteries and aluminum-cased cylindrical batteries. In a steel-cased cylindrical battery, the negative electrode connection region 302 is disposed between a positive electrode tab connection region 201 and a negative electrode tab connection region 301. In an aluminum-cased cylindrical battery, the positive electrode connection region 202 is disposed between a positive electrode tab connection region 201 and a negative electrode tab connection region 301. For example... Figure 1 and Figure 4 As shown, in this embodiment, the cylindrical battery cover assembly is applied to a steel-cased cylindrical battery, that is, the negative electrode terminal connection area 302 is disposed between the positive electrode tab connection area 201 and the negative electrode tab connection area 301.

[0047] At this point, the ratio of thickness b to thickness a satisfies 0.25 ≤ b / a ≤ 0.9. In this embodiment, the negative electrode terminal connection area 302 is disposed between the positive electrode tab connection area 201 and the negative electrode tab connection area 301. Since tab connection areas (positive electrode tab connection area 201 and negative electrode tab connection area 301) are provided on both sides of the terminal connection area (negative electrode terminal connection area 302), the overall heat dissipation capacity of the tab connection area can be improved, ensuring balanced heat dissipation of the tab connection areas on both sides of the terminal connection area. Therefore, the lower limit of the ratio of the thickness b of the tab connection area to the thickness a of the terminal connection area can be larger, so that the thickness of the tab connection area is thicker, achieving a better current flow effect. For example, the ratio of thickness b to thickness a can be 0.25, 0.4, 0.7, 0.9, etc.

[0048] Furthermore, the positive electrode tab connection area 201 and the negative electrode tab connection area 301 include a fan-shaped structure. The positive electrode tab connection area 201 and the negative electrode tab connection area 301 are arranged around the positive electrode post connection area 202 or the negative electrode post connection area 302. 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. The range of the central angle of the positive electrode tab connection area 201 and the range of the central angle of the negative electrode tab connection area 301 are both 75°~175°.

[0049] The positive electrode tab connection area 201 and the negative electrode tab connection area 301 include a fan-shaped structure. The positive electrode tab connection area 201 and the negative electrode tab connection area 301 are arranged around the positive electrode post connection area 202 or the negative electrode post connection area 302. In this embodiment, the positive electrode tab connection area 201 and the negative electrode tab connection area 301 are arranged around the negative electrode post connection area 302, and the negative electrode post connection area 302 is located at the center of the positive electrode tab connection area 201 and the negative electrode tab connection area 301.

[0050] The sum of the central angle of the positive electrode connection region 201 and the central angle of the negative electrode connection region 301 ranges from 150° to 350°, ensuring that the areas of the positive electrode connection region 201 and the negative electrode connection region 301 are large enough to guarantee their current-carrying capacity. For example, the sum of the central angles of the positive electrode connection region 201 and the negative electrode connection region 301 can be 150°, 210°, 300°, 350°, etc.

[0051] At this point, the ratio of thickness b to thickness a satisfies 0.28 ≤ b / a ≤ 0.85. In this embodiment, the areas of the positive electrode tab connection region 201 and the negative electrode tab connection region 301 are large enough to improve the overall heat dissipation capacity of the tab connection region and ensure balanced heat dissipation on both sides of the electrode connection region. Therefore, the lower limit of the ratio of thickness b of the tab connection region to thickness a of the electrode connection region can be larger to make the thickness of the tab connection region thicker and achieve better current flow. For example, the ratio of thickness b to thickness a can be 0.28, 0.3, 0.6, 0.85, etc.

[0052] In this embodiment, the central angle of the positive electrode connection region 201 ranges from 75° to 175°. For example, the central angle of the positive electrode connection region 201 can be 75°, 82°, 120°, 175°, etc. The central angle of the negative electrode connection region 301 also ranges from 75° to 175°. For example, the central angle of the negative electrode connection region 301 can be 75°, 95°, 110°, 175°, etc. However, the central angles of the positive electrode connection region 201 and the negative electrode connection region 301 are not necessarily equal; they may or may not be equal.

[0053] Furthermore, the electrode connection area located between the positive electrode tab connection area 201 and the negative electrode tab connection area 301 is made of copper. The ratio of the thickness of the positive electrode tab connection area 201 to the thickness of the positive electrode connection area 202 is in the range of 0.3 to 0.8, and the ratio of the thickness of the negative electrode tab connection area 301 to the thickness of the negative electrode connection area 302 is also in the range of 0.3 to 0.8.

[0054] The electrode connection area located between the positive electrode tab connection area 201 and the negative electrode tab connection area 301 is made of copper. That is, the electrode connection area located between the positive electrode tab connection area 201 and the negative electrode tab connection area 301 is called the negative electrode electrode connection area 302. At this time, the ratio of the thickness of the positive electrode tab connection area 201 to the thickness of the positive electrode electrode connection area 202 is in the range of 0.3 to 0.8. For example, the ratio of the thickness of the positive electrode tab connection area 201 to the thickness of the positive electrode electrode connection area 202 is 0.3, 0.5, 0.7, 0.8, etc. The ratio of the thickness of the negative electrode tab connection area 301 to the thickness of the negative electrode electrode connection area 302 is also in the range of 0.3 to 0.8. For example, the ratio of the thickness of the negative electrode tab connection area 301 to the thickness of the negative electrode electrode connection area 302 is 0.3, 0.65, 0.75, 0.8, etc. Because copper has better heat dissipation performance, the lower limit of the ratio of the thickness b of the tab connection area to the thickness a of the pole connection area with the same polarity can be larger, so that the thickness of the tab connection area can be thicker, so as to achieve good heat dissipation and current carrying capacity at the same time.

[0055] Furthermore, the positive current collector 2 and the negative current collector 3 are connected by 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 0.5~1.

[0056] like Figure 3 and Figure 4 As shown, in this embodiment, the current collector 1 is an integrated structure, that is, the positive current collector 2 and the negative current collector 3 are integrated into one unit, and the positive current collector 2 and the negative current collector 3 are insulated from each other. Specifically, the positive current collector 2 and the negative current collector 3 are connected to each other as an integrated structure through the insulating member 8, that is, the insulating member 8 is connected to both the positive current collector 2 and the negative current collector 3, so that the positive current collector 2, the negative current collector 3 and the insulating member 8 form an integral structure, which is the current collector 1.

[0057] The insulating component 8 is made of insulating materials such as resin and plastic. The positive current collector 2, the negative current collector 3, and the insulating component 8 can be connected together by means of hot melting, injection molding, etc. Of course, after the positive current collector 2 and the negative current collector 3 are connected to the insulating component 8, the positive current collector 2 and the negative current collector 3 remain insulated from each other. In addition, the positive current collector 2 and the negative current collector 3 are located on the side of the battery cell where the tabs are provided to facilitate subsequent connection of the tabs.

[0058] The insulating component 8 has a circular structure, and its outer ring structure is suitable for cooperating with the positive electrode post connection area 202. The middle part of the insulating component 8 has two hollow parts, namely the first hollow part 801 and the second hollow part 802. The first hollow part 801 is correspondingly matched with the negative electrode current collector 3, and the negative electrode current collector 3 is disposed at the first hollow part 801. The second hollow part 802 is correspondingly matched with the positive electrode tab connection area 201, and the positive electrode tab connection area 201 is disposed at the second hollow part 802.

[0059] 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 by the insulating member 8, since the position of the insulating member 8 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 and 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, making it difficult to fix the insulating member 8, and thus causing the entire current collector 1 to tilt.

[0060] 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 and 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, making it easy for the insulating component 8 to be connected and fixed with the positive electrode current collector 2 and the negative electrode current collector 3, and the entire current collector 1 will not tilt.

[0061] To facilitate molding, the thickness of both the pole connection area and the tab connection area of ​​the current collector 1 is uniform. In the pole connection area, a portion is welded to the pole, while another portion is not. The portion not welded to the pole constitutes the effective area of ​​the pole connection area. Similarly, in the tab welding area, a portion is welded to the tab, while another portion is not. The portion not welded to the tab constitutes the effective area of ​​the tab connection area. During measurement, the thickness of the effective area of ​​the pole connection area characterizes the thickness of the entire pole connection area, and similarly, the thickness of the effective area of ​​the tab connection area characterizes the thickness of the entire tab connection area.

[0062] Furthermore, the positive electrode tab connection area 201 and the negative electrode tab connection area 301 are arranged around the positive electrode post connection area 202 or the negative electrode post connection area 302. 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. At this time, the ratio of thickness b to thickness a satisfies 0.6≤b / a≤0.8.

[0063] like Figure 1 , 3As shown in Figure 4, in this embodiment, the cylindrical battery cover assembly is applied to a steel-cased cylindrical battery. Therefore, the positive electrode tab connection area 201 and the negative electrode tab connection area 301 are arranged around the negative electrode terminal connection area 302. The positive electrode tab connection area 201 and the negative electrode tab connection area 301 include a fan-shaped structure. The positive electrode tab connection area 201 includes a fan-shaped structure, which is connected to the positive electrode tab. There are outwardly protruding connecting plates 203 on both sides of the fan-shaped structure. The connecting plates 203 are used to connect the insulating component 8. 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 to 1. For example, 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 can be 0.5, 0.7, 0.9, 1, etc.

[0064] At this point, 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 connection area 201 to the central angle of the negative electrode connection area 301 is within the above range, and the central angles of the positive electrode connection area 201 and the negative electrode connection area 301 are relatively close, the lower limit of the ratio of thickness b to thickness a can be set larger to make the electrode connection area thicker and achieve a better current flow effect.

[0065] Furthermore, the pole connection area is provided with a protrusion 7, where the ratio of thickness b to thickness a satisfies 0.2≤b / a≤0.8.

[0066] A protrusion 7 is provided in the terminal connection area. In this embodiment, the protrusion 7 is provided in the negative terminal connection area 302, and the protrusion 7 extends and protrudes towards the negative terminal 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 terminal connection area, the contact surface between the terminal connection area and the cover body is larger, and the heat dissipation is better. Therefore, the thickness of the terminal connection area can be thicker, that is, the upper limit of the range of the ratio 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.

[0067] Furthermore, the pole post has a groove 6 facing the current collector 1, and a protrusion 7 is at least partially placed in the groove 6. The protrusion 7 is connected to the pole post. A flange 10 is provided on the side edge of the groove 6 near the current collector 1. The flange 10 is located between the current collector 1 and the cover plate body. The overlapping area of ​​the flange 10 and the electrode tab connection area is m, and the area of ​​the electrode tab connection area is d. The ratio of area m to area d satisfies 0.05≤m / d≤0.4.

[0068] like Figures 1-2As shown, the cylindrical battery cover assembly also includes a cover body, which has a disc-shaped structure, and the diameter of the cover body matches that of the current collector 1. The cover body is the positive terminal 4, and a through hole is formed at the center of the cover body. A portion of the negative terminal 5 is adapted to pass through this through hole so that the negative terminal 5 and the positive terminal 4 can be assembled and connected. After the negative terminal 5 and the positive terminal 4 are assembled, they are insulated from each other. For example, an insulating ring can be provided at the connection position between the negative terminal 5 and the positive terminal 4.

[0069] After the negative terminal 5 and the positive terminal 4 are assembled, one side of the negative terminal 5 faces the current collector 1. Figure 1 Taking the shown viewpoint as an example, the bottom of the negative terminal 5 faces the current collector 1. The side of the negative terminal 5 facing the current collector 1 mates with the negative terminal connection area 302.

[0070] The electrode post has a groove 6 facing the current collector 1. Specifically, the negative electrode post 5 has a groove 6 facing the current collector 1, that is, the opening of the groove 6 faces the current collector 1, and the protrusion 7 protrudes towards the negative electrode post 5. The size and shape of the groove 6 match the size and shape of the protrusion 7, and the protrusion 7 is at least partially inserted into the groove 6 and placed within the groove 6. In this embodiment, the cross-sections of both the groove 6 and the protrusion 7 perpendicular to the axial direction are circular, and the axial direction of the groove 6 and the protrusion 7 is... Figure 1 The vertical direction of the viewing angle. The inner wall of the groove 6 and the outer wall of the protrusion 7 are clearance-fitted. In this embodiment, the groove 6 and the protrusion 7 are clearance-fitted in the circumferential direction so that the protrusion 7 can be smoothly and conveniently inserted into the groove 6, which facilitates the subsequent welding of the protrusion 7 to the negative electrode post 5.

[0071] A flange 10 is provided on the edge of the groove 6 near the current collector 1. The flange 10 is located between the current collector 1 and the cover plate body to improve the reliability of the structural connection. The flange 10 is located between the current collector 1 and the cover plate body. The overlap area between the flange 10 and the electrode connection area is m, and the area of ​​the electrode connection area is d. The ratio of area m to area d satisfies 0.05 ≤ m / d ≤ 0.4. In this embodiment, the overlap area between the flange 10 and the negative electrode connection area 301 is m, and the area of ​​the negative electrode connection area 301 is d. 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 and the electrode connection area have a certain overlap area, which can improve heat dissipation performance. However, the overlap area should not be too large, otherwise there is a risk of insulation failure. A ratio of area m to area d within the above range is beneficial for improving heat dissipation performance and ensuring insulation.

[0072] This embodiment also provides a battery, including the cylindrical battery cover assembly as described above and a battery cell. The battery cell includes a tab, which is connected to the tab connection area of ​​the current collector in the cover assembly. The orthographic projection area of ​​the tab on the current collector 1 is c, and the area of ​​the tab connection area is d. The ratio of area c to area d satisfies 0.5 ≤ c / d < 1.

[0073] like Figure 5 As shown, the battery in this embodiment is a cylindrical battery with the positive and negative electrodes led out on the same side. The battery has a battery casing 9, within which are structures such as a battery cell and a cover assembly. The battery cell includes a positive electrode tab and a negative electrode tab, which are located on the same side of the battery cell to achieve simultaneous lead-out of the positive and negative electrodes. Of course, the battery in this embodiment also has other structures and components common to existing batteries, which will not be elaborated here.

[0074] During the battery manufacturing process, the positive electrode tab and positive electrode post 4 are connected to the positive current collector 2, and the positive current collector 2 is subsequently connected to the battery casing 9. The negative electrode tab and negative electrode post 5 are connected to the negative current collector 3.

[0075] The projected area of ​​the battery cell's tab on the current collector 1 is c, and the area of ​​the tab connection area is d. 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. A ratio of area c to area d within the above range allows for sufficient heat dissipation space and ensures the current carrying capacity of the tab connection area.

[0076] Furthermore, multiple electrodes are provided, and the multiple electrodes are spaced apart along the circumference, with the spacing between adjacent electrodes ranging from 0.05mm to 1mm.

[0077] In this embodiment, multiple electrodes are provided, including multiple positive electrodes and multiple negative electrodes, which are spaced apart circumferentially. Of course, the positive and negative electrodes must maintain a certain distance to ensure insulation. The spacing between adjacent electrodes ranges from 0.05mm to 1mm; for example, the spacing between adjacent electrodes can be 0.05mm, 0.068mm, 0.08mm, 1mm, etc. Within this range, sufficient space for heat dissipation is provided, improving the heat dissipation effect.

[0078] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A cylindrical battery cover assembly, characterized in that, Applied to a battery, the battery includes a cell, the cell includes tabs, the tabs include a positive tab and a negative tab, the positive tab and the negative tab are disposed on the same side of the cell; the cylindrical battery cover assembly includes: pole; The current collector (1) includes a tab connection area and a post connection area. The tab connection area is connected to the tab, and the post connection area is connected to the post to realize the electrical connection between the tab and the post. The thickness of the post connection area is a, and the thickness of the tab connection area is b. The ratio of thickness b to thickness a satisfies 0.2≤b / a<1. The current collector (1) includes a positive current collector (2) and a negative current collector (3). The positive current collector (2) and the negative current collector (3) are connected into an integral structure by an insulating member (8). The positive current collector (2) includes a positive electrode tab connection area (201) and a positive electrode post connection area (202), and 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 disposed between the positive electrode tab connection area (201) and the negative electrode tab connection area (301). The positive electrode tab connection region (201) and the negative electrode tab connection region (301) include a fan-shaped structure; The ratio of the thickness of the negative electrode tab connection region (301) to the thickness of the positive electrode tab connection region (201) is in the range of 0.5 to 1.

2. The cylindrical battery cover assembly according to claim 1, characterized in that, The ratio of the thickness b to the thickness a satisfies 0.25 ≤ b / a ≤ 0.

9.

3. The cylindrical battery cover assembly according to claim 2, characterized in that, The positive electrode tab connection area (201) and the negative electrode tab connection area (301) are arranged around the positive electrode post connection area (202) or the negative electrode post connection area (302). 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 the thickness b to the thickness a satisfies 0.28≤b / a≤0.

85. The range of the central angle of the positive electrode tab connection area (201) and the range of the central angle of the negative electrode tab connection area (301) are both 75°~175°.

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

8.

5. 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) are arranged around the positive electrode post connection area (202) or the negative electrode post connection area (302). 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. At this time, the ratio of the thickness b to the thickness a satisfies 0.6≤b / a≤0.

8.

6. A battery, characterized in that, The battery includes a cylindrical battery cover assembly as described in any one of claims 1-5 and a battery cell, wherein the battery cell includes a tab, the tab is connected to the tab connection area of ​​the current collector (1) in the cylindrical battery cover assembly, the orthographic projection area of ​​the tab on the current collector 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.

7. The battery according to claim 6, characterized in that, The electrode tabs are provided in multiple ways, and the multiple electrode tabs are arranged at intervals along the circumference, with the distance between adjacent electrode tabs ranging from 0.05mm to 1mm.

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