Quick charging battery structure

Abstract

The utility model relates to and discloses a quick-charging battery structure. Relates to the technical field of new energy batteries. The battery pack specifically comprises a shell, a battery cell and a top cover assembly, a cavity is formed in the shell, the top of the cavity is open, the battery cell is arranged in the cavity, and the top cover assembly is used for closing the top opening of the cavity; the battery cell comprises a roll core wound into multiple circles, one circle of roll core is provided with at least two positive plates and at least two negative plates, all the positive plates of the roll core are gathered to form a positive lug of the battery cell, and all the negative plates of the roll core are gathered to form a negative lug of the battery cell. The at least two positive plates and the at least two negative plates are arranged in each circle of roll core, all the positive plates of the roll core are gathered together to form a positive lug of the battery core, and all the negative plates of the roll core are gathered together to form a negative lug of the battery core, so that the internal resistance of the battery core is reduced, the overcurrent capacity of the battery core is enhanced, and the service life of the battery core is prolonged. And therefore, the battery can meet the high-rate charging and discharging requirements.

Description

Technical Field

[0001] The utility model relates to the technical field of new energy batteries, in particular to a fast-charging battery structure. Background Art

[0002] With the development of society, people's pace of life is gradually accelerating, and the demand for fast-charging batteries is gradually increasing. The conventional wound battery cell structure is formed by first coating the positive electrode material + diaphragm + negative electrode material into a three-layer core, and then winding the core multiple times. In the existing wound battery cell structure, each turn of the core is provided with a positive electrode ear and a negative electrode ear. After the core is wound, the multiple positive ears of the multiple turns of the core are welded together to form the positive ear of the battery cell structure, and the multiple negative ears of the multiple turns of the core are welded together to form the negative ear of the battery cell structure. However, this battery cell structure has a large internal resistance and poor current capacity, which cannot meet the current needs of fast-charging batteries.

[0003] Chinese patent CN218385353U, published on 2023-01-24, discloses a wound battery cell, the wound battery cell comprising: a first pole piece, a second pole piece and a diaphragm arranged in a winding manner, the diaphragm is arranged between the first pole piece and the second pole piece, the second pole piece is in the innermost layer, the first pole piece comprises a plurality of alternatingly connected planar segments and curved segments, and the surface of at least one curved segment close to the innermost second pole piece is provided with a positive electrode material coating, and the gram capacity of the positive electrode material coating is 110-150mAh / g. After the first pole piece and the second pole piece are wound, they both have a plurality of curved segments, and a positive electrode material coating with low gram capacity and good safety performance is arranged between the curved segment of the first pole piece and the curved segment of the second pole piece. The internal resistance of the wound battery cell is large and the current carrying capacity is poor, which cannot meet the needs of current fast-charging batteries. Utility Model Content

[0004] The purpose of the present utility model is to provide a fast-charging battery structure to address the deficiencies of the above-mentioned prior art, which can reduce the internal resistance of the battery cell and enhance the current carrying capacity of the battery cell, so that the battery can achieve high-rate charging and discharging requirements while ensuring the safety performance of the battery.

[0005] The utility model proposes a fast-charging battery structure, comprising a shell, a battery cell and a top cover assembly, wherein a cavity is arranged in the shell, the top of the cavity is open, the battery cell is arranged in the cavity, and the top cover assembly is used to close the top opening of the cavity; the battery cell comprises a winding core wound into multiple turns, one turn of the winding core is provided with at least two positive electrode sheets and at least two negative electrode sheets, all the positive electrode sheets of the winding core are gathered together to form a positive electrode ear of the battery cell, and all the negative electrode sheets of the winding core are gathered together to form a negative electrode ear of the battery cell.

[0006] Furthermore, the two positive electrode sheets are relatively arranged on the inner side of a circle of the winding core, and the two negative electrode sheets are relatively arranged on the outer side of a circle of the winding core.

[0007] Furthermore, all the positive electrode sheets of the winding core are gathered together by ultrasonic welding to form the positive electrode ear of the battery cell, and all the negative electrode sheets of the winding core are gathered together by ultrasonic welding to form the negative electrode ear of the battery cell.

[0008] Furthermore, the top cover assembly includes a cover plate, a positive electrode column arranged on the cover plate, a negative electrode column arranged on the cover plate, and an injection hole arranged on the cover plate, the positive electrode column is used to lead out the positive electrode of the battery cell, the negative electrode column is used to lead out the negative electrode of the battery cell, and the injection hole is used to inject electrolyte into the cavity.

[0009] Furthermore, the positive electrode column is connected to the positive electrode ear to lead out the positive electrode of the battery cell, and the negative electrode column is connected to the negative electrode ear to lead out the negative electrode of the battery cell.

[0010] Furthermore, the positive electrode column and the positive electrode lug are connected by laser welding, and the negative electrode column and the negative electrode lug are connected by laser welding.

[0011] Furthermore, the positive electrode column can be connected to the positive electrode ears of the two battery cells at the same time, the negative electrode column can be connected to the negative electrode ears of the two battery cells at the same time, and the cavity can accommodate the two battery cells at the same time.

[0012] Furthermore, the battery structure also includes a V-shaped limiting piece, which is inserted into the roots of the positive electrode ear and the negative electrode ear to limit the positive electrode ear and the negative electrode ear from extending in a direction away from the winding core.

[0013] Furthermore, the connection between the positive electrode column and the positive electrode ear, and the connection between the negative electrode column and the negative electrode ear are both affixed with PET tape.

[0014] Furthermore, an explosion-proof valve for protecting the battery and a protective patch for protecting the explosion-proof valve are provided at the bottom of the shell, and the protective patch is provided on the outside of the explosion-proof valve.

[0015] The utility model provides a fast-charging battery structure with the following gain effects:

[0016] (1) Each winding core of the battery structure is provided with at least two positive electrode sheets and at least two negative electrode sheets. All the positive electrode sheets of the winding core are gathered together to form the positive electrode ears of the battery cell, and all the negative electrode sheets of the winding core are gathered together to form the negative electrode ears of the battery cell, thereby reducing the internal resistance of the battery cell and enhancing the current capacity of the battery cell, thereby enabling the battery to achieve high-rate charge and discharge requirements;

[0017] (2) At least two positive electrode sheets of each winding core of the battery structure are arranged opposite to each other, and at least two negative electrode sheets of each winding core are arranged opposite to each other, so that the projections of all positive electrode sheets in the thickness direction of the winding core overlap, and at the same time, the projections of all negative electrode sheets in the thickness direction of the winding core also overlap, thereby reducing the processing difficulty of the battery structure and enhancing the practicality of the battery structure;

[0018] (3) The positive electrode column on the cover of the battery structure is directly connected to the positive electrode ear of the battery cell, and the negative electrode column is directly connected to the negative electrode ear of the battery cell, eliminating the adapter, thereby further reducing the internal resistance of the battery cell and enhancing the current capacity of the battery cell, thereby enabling the battery to achieve high-rate charge and discharge requirements;

[0019] (4) Two battery cells are arranged side by side in the cavity of the shell of the battery structure. The positive electrode column on the cover plate can be welded to the positive electrode ears of the two battery cells at the same time by laser welding, and the negative electrode column on the cover plate can be welded to the negative electrode ears of the two battery cells at the same time by laser welding, so that the capacity of the battery structure is larger and the energy storage capacity is stronger;

[0020] (5) The battery structure also includes a V-shaped stopper, which is inserted into the root of the positive electrode sheet and the negative electrode sheet so that the root of the positive electrode sheet and the negative electrode sheet is folded on the winding core, thereby shortening the length of the positive electrode ear and the negative electrode ear extending away from the battery cell, preventing the two battery cells connected on both sides of the cover from interfering with each other, and eliminating the cutting process, which not only reduces the production cost of the battery, but also prevents the risk of short circuit in the battery cell caused by metal debris generated by cutting;

[0021] (6) The explosion-proof valve of the battery structure is arranged on the shell, which not only protects the battery, but also solves the problem of insufficient space for placing the explosion-proof valve in the top cover assembly. A protective patch is arranged on the outside of the explosion-proof valve to protect the explosion-proof valve, thereby preventing accidental external bumps from causing damage to the explosion-proof valve, thereby further ensuring the safety performance of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the utility model and, together with the description, are used to explain the principle of the utility model. In the accompanying drawings, like reference numerals are used to represent like elements.

[0023] Figure 1 This is a structural schematic diagram of a coil core of a fast-charging battery structure according to an embodiment of the utility model;

[0024] Figure 2 A schematic diagram of the structure of a battery cell of a fast-charging battery structure according to an embodiment of the utility model;

[0025] Figure 3This is a cross-sectional view of a V-shaped limiter plugged into a positive electrode tab of a battery cell of a fast-charging battery structure according to an embodiment of the utility model;

[0026] Figure 4 This is a structural schematic diagram of a fast-charging battery structure of an embodiment of the utility model, in which a top cover assembly without PET tape is connected to a battery cell;

[0027] Figure 5 This is a structural schematic diagram of a fast-charging battery structure of an embodiment of the utility model, in which a top cover assembly with PET tape applied is connected to a battery cell;

[0028] Figure 6 An exploded view of a fast-charging battery structure according to an embodiment of the utility model.

[0029] In the figure: 1. Shell; 11. Explosion-proof valve; 12. Protection patch; 2. Battery cell; 21. Winding core; 211. Positive electrode sheet; 212. Negative electrode sheet; 213. Diaphragm; 22. Positive electrode ear; 23. Negative electrode ear; 3. Top cover assembly; 31. Cover plate; 32. Positive electrode column; 33. Negative electrode column; 34. Liquid injection hole; 4. V-shaped limiter; 5. PET tape. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of the embodiments of the utility model clearer, the technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0031] A fast-charging battery structure of an embodiment of the utility model comprises a shell 1, a battery cell 2 and a top cover assembly 3. A cavity is arranged in the shell 1, the top of the cavity is open, the battery cell 2 is arranged in the cavity, and the top cover assembly 3 is used to close the top opening of the cavity; the battery cell 2 comprises a winding core 21 wound into multiple turns, one turn of the winding core 21 is provided with at least two positive electrode sheets 211 and at least two negative electrode sheets 212, all the positive electrode sheets 211 of the winding core 21 are gathered together to form a positive electrode ear 22 of the battery cell 2, and all the negative electrode sheets 212 of the winding core 21 are gathered together to form a negative electrode ear 23 of the battery cell 2, see Figure 1 , Figure 2 and Figure 6 .

[0032] In the present application, the battery structure includes a shell 1, a battery cell 2 and a top cover assembly 3. A cavity is provided in the shell 1, and the top of the cavity is open. The top cover assembly 3 is used to close the top opening of the cavity. When the top cover assembly 3 is not installed, the battery cell 2 can be placed in the cavity through the opening, so that the shell 1 can accommodate the battery cell 2, and then the top opening of the cavity is closed by the top cover assembly 3, thereby forming a complete battery structure.

[0033] With the development of science and technology, batteries, as the energy source of most technological products, are becoming more and more important. At present, wound cells 2 are being used more and more widely as a battery structure with high energy density that is easy to produce. The conventional wound cell structure is formed by first coating the positive electrode material + separator + negative electrode material into a three-layer structure of the winding core, and then winding the winding core multiple times. In the existing wound cell structure, each winding core is provided with a positive electrode ear and a negative electrode ear.

[0034] After the winding of the core is completed, the multiple positive ears of the multi-turn core are welded together to form the positive ears of the battery structure, and the multiple negative ears of the multi-turn core are welded together to form the negative ears of the battery structure. The positive electrode of the battery structure is led out through the positive ear, and the negative electrode of the battery structure is led out through the negative ear. With the development of society, people's pace of life is gradually accelerating, and the demand for fast-charging batteries is gradually increasing. However, the current battery structure has a large internal resistance and poor current capacity, which can no longer meet the current needs of fast-charging batteries.

[0035] Therefore, in the present application, the battery cell 2 includes a core 21 wound into multiple turns, and at least two positive electrode sheets 211 and at least two negative electrode sheets 212 are provided in each turn of the core 21. After the core 21 is wound into multiple turns, all the positive electrode sheets 211 of the core 21 are gathered together to form a positive electrode ear 22 of the battery cell 2, and at the same time, all the negative electrode sheets 212 of the core 21 are gathered together to form a negative electrode ear 23 of the battery cell 2. The positive electrode of the battery cell 2 is led out through the positive electrode ear 22, and the negative electrode of the battery cell 2 is led out through the negative electrode ear 23, thereby reducing the internal resistance of the battery cell 2 and enhancing the current capacity of the battery cell 2, so that the battery can achieve high-rate charging and discharging requirements.

[0036] In this embodiment, the two positive electrode sheets 211 are disposed on the inner side of a circle of winding core 21, and the two negative electrode sheets 212 are disposed on the outer side of a circle of winding core 21. Figure 1 . In the present application, the core 21 is a three-layer structure formed by laminating positive electrode material + separator 213 + negative electrode material. Specifically: the positive electrode material can be set in the inner layer, the separator 213 can be set in the middle layer, and the negative electrode material can be set in the outer layer. When the core 21 is wound one circle, the two positive electrode sheets 211 are arranged relatively on the positive electrode material of the inner layer of the core 21, so that the positive electrode material of the core 21 is drained through the two positive electrode sheets 211; the two negative electrode sheets 212 are arranged relatively on the negative electrode material of the outer layer of the core 21, so that the negative electrode material of the core 21 is drained through the two negative electrode sheets 212, thereby reducing the internal resistance of the battery cell 2 and enhancing the current capacity of the battery cell 2.

[0037] The reason why the two positive electrode sheets 211 of each circle of the winding core 21 are arranged opposite to each other and the two negative electrode sheets 212 of each circle of the winding core 21 are arranged opposite to each other is to make the projections of all the positive electrode sheets 211 in the thickness direction of the winding core 21 overlap, and at the same time, all the negative electrode sheets 212 also overlap in the thickness direction of the winding core 21. This makes it convenient to fold all the positive electrode sheets 211 of the winding core 21 toward one side after the winding of multiple circles is completed to gather all the positive electrode sheets 211 together to form the positive electrode ear 22 of the battery cell 2. At the same time, all the negative electrode sheets 212 of the winding core 21 are folded toward one side to gather all the negative electrode sheets 212 together to form the negative electrode ear 23 of the battery cell 2, thereby reducing the processing difficulty of the battery structure and enhancing the practicability of the battery structure.

[0038] In this embodiment, all the positive electrode sheets 211 of the winding core 21 are gathered together by ultrasonic welding to form the positive electrode ear 22 of the battery cell 2, and all the negative electrode sheets 212 of the winding core 21 are gathered together by ultrasonic welding to form the negative electrode ear 23 of the battery cell 2. In this application, after the winding core 21 has completed multiple turns of winding, all the positive electrode sheets 211 of the winding core 21 are folded toward one side so that all the positive electrode sheets 211 are superimposed together, and then all the superimposed positive electrode sheets 211 are connected by ultrasonic welding to form an integral structure, thereby completing the production of the positive electrode ear 22 of the battery cell 2; all the negative electrode sheets 212 of the winding core 21 are folded toward one side so that all the negative electrode sheets 212 are superimposed together, and then all the superimposed negative electrode sheets 212 are connected by ultrasonic welding to form an integral structure, thereby completing the production of the negative electrode ear 23 of the battery cell 2.

[0039] In this embodiment, the top cover assembly 3 includes a cover plate 31, a positive electrode column 32 provided on the cover plate 31, a negative electrode column 33 provided on the cover plate 31, and a liquid injection hole 34 provided on the cover plate 31, the positive electrode column 32 is used to lead out the positive electrode of the battery cell 2, the negative electrode column 33 is used to lead out the negative electrode of the battery cell 2, and the liquid injection hole 34 is used to inject electrolyte into the cavity, see Figure 4 and Figure 6 In the present application, the top cover assembly 3 includes a cover plate 31, a positive electrode column 32 and a negative electrode column 33. The positive electrode column 32 and the negative electrode column 33 are arranged on the inner side of the cover plate 31. When the cover plate 31 closes the opening at the top of the cavity of the shell 1, the positive electrode of the battery cell 2 is led out through the positive electrode column 32, and the negative electrode of the battery cell 2 is led out through the negative electrode column 33.

[0040] The cover plate 31 is also provided with a liquid injection hole 34, which penetrates the cover plate 31. When the cover plate 31 closes the opening at the top of the cavity of the shell 1, the electrolyte can be injected into the cavity of the shell 1 through the liquid injection hole 34, thereby completing the manufacture of the battery. It is foreseeable that in order to prevent the electrolyte in the shell 1 from leaking, after the electrolyte injection is completed, the liquid injection hole 34 needs to be blocked to achieve the sealing of the shell 1.

[0041] In this embodiment, the positive electrode column 32 is connected to the positive electrode ear 22 to lead out the positive electrode of the battery cell 2, and the negative electrode column 33 is connected to the negative electrode ear 23 to lead out the negative electrode of the battery cell 2. Figure 4 In the present application, when the cover plate 31 closes the opening at the top of the cavity of the shell 1, the positive pole post 32 on the cover plate 31 is directly connected to the positive pole ear 22 of the battery cell 2, so that the positive pole post 32 leads out the positive pole of the battery cell 2; the negative pole post 33 on the cover plate 31 is directly connected to the negative pole ear 23 of the battery cell 2, so that the negative pole post 33 leads out the negative pole of the battery cell 2.

[0042] In the prior art, the positive pole column 32 on the cover plate 31 and the positive pole ear 22 of the battery cell 2, and the negative pole column 33 and the negative pole ear 23 of the battery cell 2 are usually connected through an adapter, and the provision of the adapter increases the internal resistance of the battery cell 2 and reduces the flow capacity of the battery cell 2. In the present application, the positive pole column 32 on the cover plate 31 is directly connected to the positive pole ear 22 of the battery cell 2, and the negative pole column 33 is directly connected to the negative pole ear 23 of the battery cell 2, and the adapter is eliminated, thereby further reducing the internal resistance of the battery cell 2 and enhancing the flow capacity of the battery cell 2, thereby enabling the battery to achieve high-rate charge and discharge requirements.

[0043] In this embodiment, the positive electrode column 32 is connected to the positive electrode ear 22 by laser welding, and the negative electrode column 33 is connected to the negative electrode ear 23 by laser welding. In this application, after the winding core 21 completes multiple turns of winding, all the positive electrode sheets 211 of the winding core 21 are first folded to one side so that all the positive electrode sheets 211 are superimposed together, and then all the superimposed positive electrode sheets 211 are connected by ultrasonic welding to form the positive electrode ear 22 of the battery cell 2; at the same time, all the negative electrode sheets 212 of the winding core 21 are folded to one side so that all the negative electrode sheets 212 are superimposed together, and all the superimposed positive electrode sheets 211 are connected by ultrasonic welding to form the negative electrode ear 23 of the battery cell 2.

[0044] Then, by laser welding, the ultrasonic welding area of ​​the positive ear 22 of the battery cell 2 is welded to the positive electrode column 32 on the cover plate 31, and the ultrasonic welding area of ​​the negative ear 23 of the battery cell 2 is welded to the negative electrode column 33 on the cover plate 31, thereby completing the connection between the positive electrode column 32 on the cover plate 31 and the positive ear 22 of the battery cell 2, and the connection between the negative electrode column 33 on the cover plate 31 and the negative electrode column 23 of the battery cell 2. When the cover plate 31 closes the top opening of the cavity of the shell 1, the positive electrode of the battery cell 2 is led out through the positive electrode column 32 on the cover plate 31, and the negative electrode of the battery cell 2 is led out through the negative electrode column 33 on the cover plate 31.

[0045] In this embodiment, the positive electrode column 32 can be connected to the positive electrode ears 22 of the two battery cells 2 at the same time, and the negative electrode column 33 can be connected to the negative electrode ears 23 of the two battery cells 2 at the same time. The cavity can accommodate the two battery cells 2 at the same time. Figure 4and Figure 6 In the present application, two battery cells 2 can be arranged side by side in the cavity of the shell 1, and the positive electrode column 32 on the cover plate 31 can be welded to the positive electrode ears 22 of the two battery cells 2 at the same time by laser welding, and the negative electrode column 33 on the cover plate 31 can be welded to the negative electrode ears 23 of the two battery cells 2 at the same time by laser welding, so that the capacity of the battery structure is larger and the energy storage capacity is stronger.

[0046] Specifically: when all the positive electrode sheets 211 of the winding core 21 are ultrasonically welded together, the formed positive electrode ear 22 extends in the direction away from the battery cell 2; when all the negative electrode sheets 212 of the winding core 21 are ultrasonically welded together, the formed negative electrode ear 23 extends in the direction away from the battery cell 2. Therefore, the positive electrode ear 22 of one battery cell 2 and the positive electrode column 32 of the cover plate 31 can be laser welded together on one side of the cover plate 31, and the positive electrode ear 22 of another battery cell 2 and the positive electrode column 32 of the cover plate 31 can be laser welded together on the other side of the cover plate 31. Similarly, the connection between the negative electrode ears 23 of the two battery cells 2 and the negative electrode column 33 on the cover plate 31 is also the same.

[0047] After the positive ears 22 of the two battery cells 2 are connected to the positive pole column 32 of the cover plate 31 and the negative ears 23 are connected to the negative pole column 33 of the cover plate 31, the two battery cells 2 are flipped on the cover plate 31 in a direction toward each other. During this process, the positive ears 22 and the negative ears 23 extending in a direction away from the battery cells 2 are folded on the upper surface of the battery cells 2 until the two battery cells 2 located on both sides of the cover plate 31 are arranged side by side on the cover plate 31, thereby facilitating the placement of the two battery cells 2 in the cavity of the shell 1.

[0048] It can be foreseen that: in actual implementation, three, four or more battery cells 2 can be arranged in the shell 1 of the battery structure according to the capacity of the shell 1, the space on the cover plate 31 where the positive electrode column 32 can be connected to the positive electrode ear 22, and the space on the negative electrode column 33 can be connected to the negative electrode ear 23. The specific number of battery cells 2 arranged can be determined according to actual production needs.

[0049] In this embodiment, the battery structure further includes a V-shaped limiting piece 4, which is inserted into the root of the positive ear 22 and the negative ear 23 to limit the positive ear 22 and the negative ear 23 from extending in a direction away from the winding core 21. According to the description in the above embodiment, when the positive ear 22 of the two battery cells 2 is simultaneously connected to the positive pole column 32 of the cover plate 31, and the negative ear 23 is simultaneously connected to the negative pole column 33 of the cover plate 31, one of the battery cells 2 is located on one side of the cover plate 31, and the other battery cell 2 is located on the other side of the cover plate 31. At this time, the positive ear 22 and the negative ear 23 extending in a direction away from the battery cell 2 extend to the cover plate 31, corresponding to the positions of the positive pole column 32 and the negative pole column 33 of the cover plate 31, respectively, so that the positive ear 22 of the two battery cells 2 can be connected to the positive pole column 32 of the cover plate 31, and the negative ear 23 can be connected to the negative pole column 33 of the cover plate 31 by laser welding.

[0050] Due to the limited size of the cover plate 31, when the two battery cells 2 are respectively located on both sides of the cover plate 31, and the positive tabs 22 and negative tabs 23 of the two battery cells 2 extend to the cover plate 31 in opposite directions, it is possible that the sum of the lengths of the positive tabs 22 or negative tabs 23 of the two battery cells 2 exceeds the width of the cover plate 31. Therefore, in order to prevent the two battery cells 2 from interfering with each other, the positive tabs 22 or negative tabs 23 of the two battery cells 2 need to be cut to shorten the extension length of the positive tabs 22 or negative tabs 23 of the two battery cells 2. However, the cutting process increases the production cost of the battery, and the metal debris generated by the cutting may cause the battery cell 2 to have a risk of short circuit.

[0051] Therefore, in the present application, the battery structure also includes a V-shaped limiting plate 4. Before all the positive electrode sheets 211 of the core 21 are ultrasonically welded together, and before all the negative electrode sheets 212 of the core 21 are ultrasonically welded together, the V-shaped limiting plate 4 is first inserted into the roots of the positive electrode sheets 211 and the negative electrode sheets 212, so that the roots of the positive electrode sheets 211 and the negative electrode sheets 212 are folded on the core 21, and then all the positive electrode sheets 211 of the core 21 are folded toward one side so that all the positive electrode sheets 211 are stacked together, and all the negative electrode sheets 212 of the core 21 are folded toward one side so that all the negative electrode sheets 212 are stacked together, thereby shortening the length of the positive electrode sheets 211 and the negative electrode sheets 212 extending away from the core 21.

[0052] Then, by ultrasonic welding, all the positive electrode sheets 211 of the winding core 21 are welded together to form the positive electrode ear 22 of the battery cell 2, and all the negative electrode sheets 212 of the winding core 21 are welded together to form the negative electrode ear 23 of the battery cell 2. Figure 3, the length of the positive ear 22 and the negative ear 23 without the V-shaped stopper 4 is a, the length of the positive ear 22 and the negative ear 23 with the V-shaped stopper 4 is b, and the shortened length of the positive ear 22 and the negative ear 23 is (ab). By shortening the length of the positive ear 22 and the negative ear 23 extending away from the battery cell 2, the two battery cells 2 connected on both sides of the cover plate 31 are prevented from interfering with each other, and the cutting process is eliminated, which not only reduces the production cost of the battery, but also prevents the risk of short circuit of the battery cell 2 caused by metal debris generated by cutting.

[0053] In this embodiment, the connection between the positive electrode column 32 and the positive electrode ear 22, and the connection between the negative electrode column 33 and the negative electrode ear 23 are both affixed with a PET tape 5, see Figure 5 In the present application, after the positive electrode ear 22 of the battery cell 2 is welded to the positive electrode post 32 on the cover plate 31, a PET tape 5 is applied to the outside of the welding area between the positive electrode ear 22 and the positive electrode post 32; after the negative electrode ear 23 of the battery cell 2 is welded to the negative electrode post 33 on the cover plate 31, a PET tape 5 is applied to the outside of the welding area between the negative electrode ear 23 and the negative electrode post 33, so that the PET tape 5 plays the role of insulation and blocking welding slag.

[0054] When the fast-charged battery is charged and discharged, the heat generated by the current passing through the welding points between the positive ear 22 and the positive pole 32, and the negative ear 23 and the negative pole 33 is greater. The conventional 0.05mm thick tape is easily shrunk and wrinkled after being heated, which affects the insulation and barrier effects of the tape and may cause the battery to short-circuit. Therefore, in this application, the thickness of the PET tape 5 is preferably 0.15-0.5mm, so as to avoid deformation and shrinkage of the tape due to heat and ensure the insulation effect of the tape.

[0055] In this embodiment, the bottom of the housing 1 is provided with an explosion-proof valve 11 for protecting the battery, and a protective patch 12 for protecting the explosion-proof valve 11. The protective patch 12 is arranged outside the explosion-proof valve 11. Figure 6 In the present application, an explosion-proof valve 11 is provided at the bottom of the housing 1. When the battery cell 2 experiences thermal runaway, the high-temperature and high-pressure substances inside the housing 1 will be dissipated to the outside through the explosion-proof valve 11, thereby avoiding explosion of the battery and ensuring the safety performance of the battery.

[0056] Specifically, a countersunk hole in the shape of the explosion-proof valve 11 can be formed at the bottom of the shell 1, and the explosion-proof valve 11 can be welded to the sink of the countersunk hole at the bottom of the shell 1, so as to prevent the explosion-proof valve 11 set at the bottom of the shell 1 from forming a bulge at the bottom of the shell 1, which not only affects the appearance of the battery structure, but also increases the risk of the explosion-proof valve 11 falling off. In the present application, a protective patch 12 is also provided on the outside of the explosion-proof valve 11, and the explosion-proof valve 11 is protected by the protective patch 12, so as to prevent the explosion-proof valve 11 from being damaged due to accidental bumps from the outside, and further ensure the safety performance of the battery.

[0057] In the prior art, the explosion-proof valve 11 of the battery is generally arranged on the top cover assembly 3, but in the present application, since the adapter is cancelled, the positive pole ear 22 of the battery cell 2 is directly connected to the positive pole column 32 of the cover plate 31, and the negative pole ear 23 of the battery cell 2 is directly connected to the negative pole column 33 of the cover plate 31. In the above embodiment, the positive pole column 32 on the cover plate 31 may be connected to the positive pole ears 22 of multiple battery cells 2 at the same time, and the negative pole column 33 may be connected to the negative pole ears 23 of multiple battery cells 2 at the same time, so the area of ​​the positive pole column 32 and the negative pole column 33 of the cover plate 31 is also increased accordingly, so as to meet the high overcurrent requirement. However, the space on the cover plate 31 is limited, so in the present application, the explosion-proof valve 11 is arranged on the housing 1, which can not only protect the battery, but also solve the problem of insufficient space for placing the explosion-proof valve 11 in the top cover assembly 3.

[0058] The contents described above can be implemented individually or in combination in various ways, and these variations are all within the protection scope of the present utility model.

[0059] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device comprising the elements.

[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model is described in detail with reference to the above embodiments, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the above embodiments, or replace some of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the utility model.

Claims

1. A fast-charging battery structure, characterized in that: The invention comprises a shell (1), a battery cell (2) and a top cover assembly (3); the shell (1) is provided with a cavity, the top of the cavity is open, the battery cell (2) is arranged in the cavity, and the top cover assembly (3) is used to close the top opening of the cavity; the battery cell (2) comprises a winding core (21) wound into a plurality of turns, one turn of the winding core (21) is provided with at least two positive electrode sheets (211) and at least two negative electrode sheets (212); all the positive electrode sheets (211) of the winding core (21) are gathered together to form a positive electrode ear (22) of the battery cell (2), and all the negative electrode sheets (212) of the winding core (21) are gathered together to form a negative electrode ear (23) of the battery cell (2).

2. A fast-charging battery structure as claimed in claim 1, characterized in that: The two positive electrode sheets (211) are arranged relatively on the inner side of a circle of the winding core (21), and the two negative electrode sheets (212) are arranged relatively on the outer side of a circle of the winding core (21).

3. A fast-charging battery structure as claimed in claim 1, characterized in that: All the positive electrode sheets (211) of the winding core (21) are gathered together by ultrasonic welding to form a positive electrode ear (22) of the battery cell (2), and all the negative electrode sheets (212) of the winding core (21) are gathered together by ultrasonic welding to form a negative electrode ear (23) of the battery cell (2).

4. A fast-charging battery structure as claimed in claim 1, characterized in that: The top cover assembly (3) comprises a cover plate (31), a positive electrode column (32) provided on the cover plate (31), a negative electrode column (33) provided on the cover plate (31), and a liquid injection hole (34) provided on the cover plate (31), wherein the positive electrode column (32) is used to lead out the positive electrode of the battery cell (2), the negative electrode column (33) is used to lead out the negative electrode of the battery cell (2), and the liquid injection hole (34) is used to inject electrolyte into the cavity.

5. A fast-charging battery structure as claimed in claim 4, characterized in that: The positive electrode column (32) is connected to the positive electrode ear (22) to lead out the positive electrode of the battery cell (2), and the negative electrode column (33) is connected to the negative electrode ear (23) to lead out the negative electrode of the battery cell (2).

6. A fast-charging battery structure as claimed in claim 5, characterized in that: The positive electrode column (32) is connected to the positive electrode lug (22) by means of laser welding, and the negative electrode column (33) is connected to the negative electrode lug (23) by means of laser welding.

7. A fast-charging battery structure as claimed in claim 5, characterized in that: The positive electrode column (32) can be connected to the positive electrode ears (22) of the two battery cells (2) at the same time, the negative electrode column (33) can be connected to the negative electrode ears (23) of the two battery cells (2) at the same time, and the cavity can accommodate the two battery cells (2) at the same time.

8. A fast-charging battery structure as claimed in claim 3, characterized in that: The battery structure further comprises a V-shaped limiting piece (4), wherein the V-shaped limiting piece (4) is inserted into the root of the positive electrode ear (22) and the negative electrode ear (23) to limit the positive electrode ear (22) and the negative electrode ear (23) from extending in a direction away from the winding core (21).

9. A fast-charging battery structure as claimed in claim 5, characterized in that: The connection between the positive electrode column (32) and the positive electrode ear (22), and the connection between the negative electrode column (33) and the negative electrode ear (23), are both affixed with PET tape (5).

10. A fast-charging battery structure as claimed in claim 1, characterized in that: The bottom of the housing (1) is provided with an explosion-proof valve (11) for protecting the battery, and a protective patch (12) for protecting the explosion-proof valve (11), wherein the protective patch (12) is arranged outside the explosion-proof valve (11).

Images