Battery capable of reducing internal resistance and battery pack

Abstract

The utility model provides a battery capable of reducing internal resistance and a battery pack, which belong to the technical field of batteries, and comprise: a housing comprising a main housing and a cover plate, the cover plate is covered on the main housing, and the cover plate is provided with a first opening; the battery cell is arranged in the main shell, the battery cell is provided with a first tab, and the first tab is a negative tab; the first pole guide assembly is arranged in the main shell, one end of the first pole guide assembly is electrically connected with the first pole lug, the other end of the first pole guide assembly extends out of the shell from the first opening, and the surface, extending out of the shell, of the first pole guide assembly is a first pole connecting surface. The battery has the beneficial effects that one end of the first pole diversion assembly is electrically connected with the negative tab, and the other end of the first pole diversion assembly extends out of the shell from the first opening and extends out of the surface to serve as a first pole connecting surface, so that the winding core current can be directly guided out through the first pole diversion assembly, and the main shell and the cover plate with relatively high resistivity are prevented from participating in the diversion process; the ohmic internal resistance of the whole battery cell is reduced, so that the fast charging performance of the battery is improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a battery and battery pack with reduced internal resistance. Background Technology

[0002] Batteries, as a portable energy source, are widely used in electric vehicles, energy storage systems, and consumer electronics. Because the power output of a single battery is limited, in practical applications, multiple batteries are usually combined into a battery pack through series or parallel connections to meet higher power and energy demands.

[0003] In existing technologies, battery designs typically require current conduction through the battery casing and cover. For example, CN218039493U discloses a battery including a casing, a cell, and an end cap structure. The end cap structure is electrically connected to the first and second tabs of the cell through a first and second electrode connection portion, respectively, and the current is conducted to the cover and the terminal post using a current collector.

[0004] For example, CN220272700U discloses a single-cell battery, which includes a battery casing, an electrode assembly, a first current collector, a first welded connection, and a second welded connection. The first current collector is disposed between the electrode assembly and a cover plate, and includes a first part and a second part that are interconnected. The first welded connection connects the casing body, the first part, and the cover plate; the second welded connection connects the second part and the first tab. In this design, the welded connection is used to conduct the current from the negative tab to the cover plate.

[0005] In the above solutions, the negative electrode tab generally needs to conduct current through the outer casing and cover. However, in actual implementation, the inventors found that the proportion of the outer casing and cover in the battery's ohmic impedance is particularly significant, resulting in a high overall internal resistance of the battery, reducing the battery's energy efficiency, generating a large amount of heat during high-rate charging and discharging, affecting the battery's lifespan and safety performance, especially in fast charging scenarios, which seriously restricts further improvement of battery performance. Utility Model Content

[0006] To address the above technical problems, this utility model provides a battery with reduced internal resistance; on the other hand, it also provides a battery pack.

[0007] The technical problem solved by this utility model can be achieved by the following technical solution:

[0008] The first aspect of this utility model is to provide a battery with reduced internal resistance, comprising:

[0009] The outer casing includes a main housing and a cover plate, the cover plate covering the main housing and having a first opening;

[0010] A battery cell is disposed within the main housing, and the battery cell has a first tab, which is a negative tab.

[0011] A first electrode guide assembly is disposed inside the main housing. One end of the first electrode guide assembly is electrically connected to the first electrode ear, and the other end of the first electrode guide assembly extends out of the housing from the first opening. The side of the first electrode guide assembly extending out of the housing is the first electrode connection surface.

[0012] Preferably, the first electrode guide component includes:

[0013] The first collector plate, one end of which abuts against the first electrode tab;

[0014] A guide fluid, one end of which abuts against the other end of the first collector plate, and the other end of which extends out of the outer casing from the first opening.

[0015] Preferably, the fluid guide includes a first part disposed near the first collector plate and a second part disposed away from the first collector plate. The first part is made of the same material as the first collector plate, and the second part is made of the same material as the external connecting piece.

[0016] Preferably, the first part is made of copper and the second part is made of aluminum.

[0017] Preferably, the battery cell further has a second tab, which is a positive tab;

[0018] The cover plate has a second opening;

[0019] It also includes: a second electrode guide assembly disposed within the main housing, one end of the second electrode guide assembly being electrically connected to the second electrode ear, the other end of the second electrode guide assembly extending out of the housing from the second opening, and the side of the second electrode guide assembly extending out of the housing being the second electrode connection surface.

[0020] Preferably, the second electrode guide assembly includes:

[0021] The second collector plate, one end of which abuts against the second electrode tab;

[0022] A pole post is disposed at the second opening, and the bottom of the pole post abuts against the other end of the second collector plate.

[0023] Preferably, the second collector includes a raised section that abuts against the bottom of the electrode post, and there is a gap between the raised section and the second electrode tab.

[0024] Preferably, the second tab and the first tab are located on the same side of the battery cell; or

[0025] The second tab and the first tab are located on opposite sides of the battery cell.

[0026] Preferably, an explosion-proof valve is provided at the bottom of the inner wall of the outer casing.

[0027] A second aspect of this invention is to provide a battery pack comprising a battery with reduced internal resistance as described above.

[0028] The advantages or beneficial effects of this utility model's technical solution are as follows:

[0029] This invention features a first electrode current guiding component, one end of which is electrically connected to the negative electrode tab, and the other end which extends out of the outer shell from the first opening and serves as the first electrode connection surface. This allows the current in the winding core to be directly discharged through the first electrode current guiding component, avoiding the participation of the main shell and cover plate with high resistivity in the current guiding process, reducing the ohmic internal resistance of the entire cell, and thus improving the fast charging performance of the battery. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of a battery with reduced internal resistance in a preferred embodiment of the present invention.

[0031] Figure 2 This is a partial enlarged view of the top A of the battery in a preferred embodiment of the present invention.

[0032] Explanation of reference numerals in the attached figures:

[0033] 1. Outer shell; 11. Main shell; 12. Cover plate; 2. Battery cell; 3. First electrode tab; 4. Second electrode tab; 5. First electrode guide assembly; 51. First collector plate; 52. Guide plate; 521. First part; 522. Second part; 6. Second electrode guide assembly; 61. Second collector plate; 611. Protruding section; 62. Electrode post; 7. First electrode connection surface; 8. Second electrode connection surface; 9. Explosion-proof valve. Detailed Implementation

[0034] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0035] It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0036] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the present invention.

[0037] Example 1

[0038] See Figure 1 and Figure 2 In a preferred embodiment of this utility model, based on the above-mentioned problems existing in the prior art, a battery with reduced internal resistance is provided, comprising:

[0039] The outer casing 1 includes a main casing 11 and a cover plate 12, the cover plate 12 covering the main casing 11, and the cover plate 12 having a first opening;

[0040] Battery cell 2 is disposed inside the main housing 11. Battery cell 2 has a first tab 3, which is a negative tab.

[0041] The first electrode guide component 5 is disposed inside the main housing 11. One end of the first electrode guide component 5 is electrically connected to the first electrode tab 3, and the other end of the first electrode guide component 5 extends out of the housing 1 from the first opening. The side of the first electrode guide component 5 extending out of the housing 1 is the first electrode connection surface 7.

[0042] Specifically, in existing technologies, the negative electrode tab in a battery structure typically requires current conduction through the casing and cover. However, in actual implementation, the inventors discovered that the casing and cover constitute a large proportion of the battery's ohmic impedance, which is the main reason for the high overall internal resistance of the battery.

[0043] Based on this discovery, this application optimizes the current conduction path of the negative electrode current to directly export the core current, so that the main casing 11 and the cover plate 12 do not participate in current conduction, thereby reducing the internal resistance of the battery.

[0044] Specifically, by setting a first pole current guiding component 5, one end of the first pole current guiding component 5 is connected to the negative electrode tab, and the other end extends directly out of the outer shell 1 from the opening of the cover plate 12, so that the current of the negative electrode tab in the winding core is directly discharged through the first pole current guiding component 5 without passing through the main shell 11 and the cover plate 12.

[0045] Based on preliminary analysis, the ohmic internal resistance of the casing involved in current conduction is 0.2mΩ~0.3mΩ. With the main casing 11 and cover plate 12, which have the highest resistivity, not involved in current conduction, the ohmic internal resistance of the battery in this embodiment can be reduced by 0.2mΩ~0.3mΩ. This reduces the rate of temperature rise during fast charging, improves the fast charging performance, reduces heat generation during high-rate charging and discharging, thereby extending battery life and improving safety.

[0046] In a preferred embodiment, the first electrode guiding component 5 includes:

[0047] The first collector plate 51, one end of the first collector plate 51 abuts against the first electrode 3;

[0048] A fluid guide 52 is provided, with one end of the fluid guide 52 abutting against the other end of the first collector plate 51, and the other end of the fluid guide 52 extending out of the outer shell 1 from the first opening.

[0049] Specifically, in this embodiment, the first current collector 51 is a negative current collector, used to collect and conduct negative current. Furthermore, the first current collector 51 is made of copper.

[0050] One end of the first collector plate 51 is installed inside the housing 1, near the first electrode 3, and in direct contact with the first electrode 3. The other end is connected to the guide fluid 52, and the other end of the guide fluid extends out from the first opening of the housing 1 to conduct current to the outside.

[0051] The first electrode connection surface 7 is the side of the guide fluid 52 that is exposed on the cover plate, which is also the negative electrode connection surface integrated into the Pack, used to realize the negative electrode output.

[0052] Furthermore, a sealing treatment can be applied between the fluid guide 52 and the cover plate 12. For example, a sealing ring can be installed or sealant can be applied to ensure a tight seal between the fluid guide 52 and the opening of the housing 1.

[0053] In a preferred embodiment, the guide fluid 52 includes a first part 521 disposed near the first collector plate 51 and a second part 522 disposed away from the first collector plate 51. The material of the first part 521 is the same as that of the first collector plate 51, and the material of the second part 522 is the same as that of the external connecting piece (not shown in the figure).

[0054] Specifically, in this embodiment, the guide fluid 52 adopts a segmented design, including a first part 521 and a second part 522. The part of the guide fluid 52 closest to the first collector plate 51 is the first part 521, which is made of the same material as the first collector plate 51, and is used to weld with the first collector plate 51 using the same metal, thus avoiding the difficulty of laser welding between dissimilar metals.

[0055] The part of the guide fluid 52 that is away from the first collector plate 51 is the second part 522, which is made of the same material as the external connecting piece and is used to weld with the external connecting piece using the same metal.

[0056] The second part 522 extends out of the outer casing 1 from the first opening to abut against the outer Pack aluminum connecting piece, so that the current of the winding core is directly discharged through the first part 521 and the second part 522 of the fluid conductor 52. The main casing 11 and the cover plate 12, which have the highest resistivity, do not participate in the current conduction, thus reducing the ohmic internal resistance of this part.

[0057] In a preferred embodiment, the first part 521 is made of copper and the second part 522 is made of aluminum.

[0058] The external connecting piece is made of aluminum.

[0059] Specifically, in this embodiment, the guide fluid 52 is a negative electrode guide column, which is made of copper-aluminum composite. The copper end is connected to the first collector plate 51, so that the negative electrode collector plate and the copper guide fluid are welded with the same metal (copper-copper welding); the aluminum end extends directly out of the cover plate and serves as the Pack output end, which is connected to the external Pack aluminum connecting piece. The Pack aluminum connecting piece and the aluminum guide fluid are welded with the same metal (aluminum-aluminum welding).

[0060] Furthermore, the fluid conductor 52 is cylindrical in shape. The first part 521 and the second part 522 are integrally formed using a copper-aluminum composite process to ensure structural strength and electrical conductivity.

[0061] In a preferred embodiment, the battery cell 2 further has a second tab 4, which is a positive tab;

[0062] The cover plate 12 has a second opening;

[0063] It also includes: a second pole guide assembly 6, which is disposed inside the main housing 11. One end of the second pole guide assembly 6 is electrically connected to the second pole tab 4, and the other end of the second pole guide assembly 6 extends out of the housing 1 from the second opening. The side of the second pole guide assembly 6 that extends out of the housing is the second pole connection surface 8.

[0064] In a preferred embodiment, the second electrode guide component 6 includes:

[0065] The second collector plate 61, one end of the second collector plate 61 abuts against the second electrode 4;

[0066] The pole post 62 is located at the second opening, and the bottom of the pole post 62 abuts against the other end of the second collector plate 61.

[0067] Specifically, in this embodiment, the second current collector 61 is the positive current collector, and the terminal 62 is the positive terminal.

[0068] The positive tab is connected to the positive current collector, which conducts the current from the positive tab to the positive current collector. The plane area where the protruding section 611 in the middle of the positive current collector is located is connected to the bottom of the positive terminal post, thus realizing the conduction of current.

[0069] The second electrode connection surface 8 is the side of the electrode post 62 that is exposed on the cover plate, which is also the positive electrode connection surface integrated into the Pack, used to realize positive electrode output.

[0070] In a preferred embodiment, the second collector plate 61 includes a protruding section 611 that abuts against the bottom of the pole post 62, and there is a gap between the protruding section 611 and the second pole tab 4.

[0071] In a preferred embodiment, the second tab 4 and the first tab 3 are located on the same side of the battery cell 2.

[0072] Specifically, in this embodiment, the battery uses positive and negative tabs on the same side. Since there are no tabless or current collectors on the other side of the cell, the height of the winding core involved in capacity is increased, increasing the internal space of the cell and improving the cell capacity.

[0073] In a preferred embodiment, an explosion-proof valve 9 is provided at the bottom of the inner wall of the outer casing 1.

[0074] Specifically, to ensure the safety and reliability of the battery, in this embodiment, an explosion-proof valve 9 is installed at the bottom of the battery. This explosion-proof valve 9 is made of high-strength, corrosion-resistant material, ensuring that it maintains its structural integrity and functional effectiveness even under extreme conditions.

[0075] The working principle of the explosion-proof valve 9 is that when excessive pressure accumulates inside the casing due to some reason (such as overheating, overpressure, etc.) or there is a risk of explosion, the explosion-proof valve 9 can be automatically or manually triggered to quickly release the internal pressure, thereby effectively preventing the casing from rupturing or an explosion accident from occurring.

[0076] In addition, the explosion-proof valve 9 can also be equipped with a sealing device to ensure that the gas or liquid inside the housing will not leak under normal working conditions, further enhancing the safety performance of the housing 1.

[0077] Furthermore, an injection port may be provided at the bottom of the outer casing 1 for injecting electrolyte into the main casing 11.

[0078] Furthermore, the main casing 11 is made of steel. As an example and not a limitation, 46 series steel is preferred. The steel casing is fitted onto the battery cell 2.

[0079] Example 2

[0080] This embodiment provides a battery with reduced internal resistance by having opposite output tabs. The only difference between this embodiment and Embodiment 1 is that the second tab 4 and the first tab 3 are located on opposite sides of the cell 2.

[0081] Correspondingly, the first electrode current guiding component 5 and the second electrode current guiding component 6 are also disposed on both sides of the cell to achieve current guiding on both the positive and negative electrodes.

[0082] Other structures are similar to those in Embodiment 1 and will not be described in detail here.

[0083] Specifically, based on preliminary analysis, the main casing 11 and the cover plate 12 account for the largest proportion of the ohmic internal resistance in the battery. In this embodiment, since neither the main casing 11 nor the cover plate 12 participates in current conduction, the ohmic internal resistance of the entire cell can be reduced.

[0084] Example 3

[0085] This utility model also provides a battery pack, including the battery with reduced internal resistance as described above.

[0086] Because the power of a single battery is limited, multiple batteries are usually connected (in series or in parallel) to form a battery pack. The internal resistance of a battery pack is equal to the sum of the internal resistance of each battery and the internal resistance of the connecting pieces. As the number of batteries connected in series increases, the internal resistance also increases, causing the battery pack to generate a lot of heat when discharging at high rates. This not only wastes energy but also seriously affects the lifespan of the battery pack.

[0087] The battery with reduced internal resistance in this embodiment reduces the ohmic internal resistance of a single cell because neither the main casing 11 nor the cover plate 12 interferes with the current conduction path. When multiple cells with reduced internal resistance are combined in series or parallel to form a battery pack, the ohmic internal resistance of the entire battery pack can be further significantly reduced, optimizing its electrical performance.

[0088] The advantages or beneficial effects of adopting the above technical solution are as follows: By setting a first electrode current guiding component, one end of which is electrically connected to the negative electrode tab, and the other end extends out of the outer shell from the first opening and the extended surface serves as the first electrode connection surface, the current of the winding core can be directly discharged through the first electrode current guiding component, avoiding the participation of the main shell and cover plate with high resistivity in the current guiding process, reducing the ohmic internal resistance of the entire cell, and thus improving the fast charging performance of the battery.

[0089] The above are merely preferred embodiments of the present utility model and are not intended to limit the implementation methods and protection scope of the present utility model. Those skilled in the art should realize that any equivalent substitutions and obvious changes made using the content of this specification and illustrations should be included within the protection scope of the present utility model.

Claims

1. A battery with reduced internal resistance, characterized in that, include: The outer casing includes a main housing and a cover plate, the cover plate covering the main housing and having a first opening; A battery cell is disposed within the main housing, and the battery cell has a first tab, which is a negative tab. A first electrode guide assembly is disposed inside the main housing. One end of the first electrode guide assembly is electrically connected to the first electrode ear, and the other end of the first electrode guide assembly extends out of the housing from the first opening. The side of the first electrode guide assembly extending out of the housing is the first electrode connection surface.

2. The battery with reduced internal resistance according to claim 1, characterized in that, The first electrode current guide component includes: The first collector plate, one end of which abuts against the first electrode tab; A guide fluid, one end of which abuts against the other end of the first collector plate, and the other end of which extends out of the outer casing from the first opening.

3. The battery with reduced internal resistance according to claim 2, characterized in that, The fluid guide includes a first part located near the first collector plate and a second part located away from the first collector plate. The first part is made of the same material as the first collector plate, and the second part is made of the same material as the external connecting piece.

4. The battery with reduced internal resistance according to claim 3, characterized in that, The first part is made of copper, and the second part is made of aluminum.

5. The battery with reduced internal resistance according to claim 1, characterized in that, The battery cell also has a second tab, which is a positive tab; The cover plate has a second opening; It also includes: a second electrode guide assembly disposed within the main housing, one end of the second electrode guide assembly being electrically connected to the second electrode ear, the other end of the second electrode guide assembly extending out of the housing from the second opening, and the side of the second electrode guide assembly extending out of the housing being the second electrode connection surface.

6. The battery with reduced internal resistance according to claim 5, characterized in that, The second electrode guide component includes: The second collector plate, one end of which abuts against the second electrode tab; A pole post is disposed at the second opening, and the bottom of the pole post abuts against the other end of the second collector plate.

7. The battery with reduced internal resistance according to claim 6, characterized in that, The second collector includes a raised section that abuts against the bottom of the pole post, and there is a gap between the raised section and the second tab.

8. The battery with reduced internal resistance according to claim 5, characterized in that, The second tab and the first tab are located on the same side of the battery cell; or The second tab and the first tab are located on opposite sides of the battery cell.

9. The battery with reduced internal resistance according to claim 5, characterized in that, An explosion-proof valve is provided at the bottom of the inner wall of the outer casing.

10. A battery pack, characterized in that, This includes batteries with reduced internal resistance as described in any one of claims 1-9.

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