Battery cell, battery and electric device

Abstract

The present application relates to the technical field of batteries. Provided are a battery cell, a battery and an electric device. The battery cell comprises a casing, electrode terminals, a wound core and a current collector, wherein the electrode terminals are arranged on the casing; the wound core is arranged inside the casing, the axial direction of the wound core being a first direction, and the wound core having a wound core hole and tabs; and at least one end of the wound core in the first direction is provided with a current collector, which comprises a central portion and peripheral portions, the central portion connecting the peripheral portions, the central portion covering the wound core hole, and the peripheral portions being electrically connected to both the tabs and the electrode terminals. The battery cell, the battery, and the electric device provided in the present application are highly reliable.

Description

Battery monomer, battery and electric device

[0001] Cross-reference to related applications

[0002] The present application is based on the Chinese patent application No. 202421825629.5, filed on July 30, 2024, and claims priority to the above-mentioned Chinese patent application, the whole content of which is incorporated herein by reference. TECHNICAL FIELD

[0003] The present application relates to the technical field of battery, in particular to a battery monomer, a battery and an electric device. BACKGROUND

[0004] New energy batteries are increasingly widely used in life and industry. New energy batteries are not only applied to energy storage power systems such as hydroelectric, thermal, wind and solar power stations, but also widely used in electric bicycles, electric motorcycles, electric vehicles and other electric vehicles.

[0005] In the related art, the metal particles remaining on the tab can enter the inside of the wound core through the core hole, which can easily cause hidden dangers. SUMMARY

[0006] Therefore, the embodiments of the present application aim to provide a battery monomer, a battery and an electric device with high reliability.

[0007] In order to achieve the above-mentioned purpose, the technical scheme of the embodiments of the present application is as follows:

[0008] The embodiments of the present application disclose a battery monomer, which comprises a shell, an electrode terminal, a wound core and a current collector. The electrode terminal is arranged in the shell. The wound core is arranged in the shell, the axial direction of the wound core is the first direction, and the wound core has a core hole and a tab. The wound core has a current collector at least at one end along the first direction, and each end of the current collector comprises a central part and a peripheral part. The central part is connected to the peripheral part, the central part is arranged on the core hole, and the peripheral part is electrically connected to the tab and the electrode terminal, respectively.

[0009] In the above technical scheme, the wound core is arranged in the shell, which can protect the wound core to some extent and improve the service life of the wound core. The current collector comprises a central part and a peripheral part, the central part is arranged on the core hole, and the peripheral part is electrically connected to the tab and the electrode terminal, respectively. In this way, the electrolyte can be prevented from bringing the remaining metal particles during the treatment of the tab into the wound core through the core hole, reducing the short circuit in the wound core and the performance degradation of the battery monomer, and improving the reliability. The wound core has tabs with opposite polarities on the opposite sides, which reduces the short circuit caused by the contact of the tabs with opposite polarities, and further improves the reliability of the battery monomer.

[0010] In an embodiment, the tab of the corresponding end of the wound cell is wrapped around the corresponding center portion in the first direction, and the center portion is arranged spaced apart from the tab.

[0011] In the above technical solution, the center portion is arranged spaced apart from the tab, so on one hand, when the center portion is covered on the cell hole, the tab is spaced apart from the center portion to reduce the situation that the tab is bent and folded, and the reliability is further improved; on the other hand, the tab is spaced apart from the center portion, which means that the number of tabs is reduced to reduce the surface density of the tab, so that not only the impregnation efficiency of the electrolyte can be improved, but also the exhaust rate inside the wound cell can be improved, and the heat dissipation performance is good.

[0012] In an embodiment, the tab includes a main body region, a bending region and a void region, the bending region has a height difference with the main body region in the first direction, the void region corresponds to the cell hole, and the peripheral portion is connected with the bending region.

[0013] In the above technical solution, by forming the bending region, the contact area with the peripheral portion can be increased, the electrical connection of the peripheral portion is facilitated, and the overcurrent capacity of the battery monomer is improved. By making the main bending region have a height difference with the main body region in the first direction, the layout of the center portion, the peripheral portion, the bending region, the main body region and the void region is more flexible, and the space is fully utilized. By forming the void region, when the center portion is covered on the cell hole, the main body region and the bending region are spaced apart from the center portion to reduce the situation that the tab is bent and folded.

[0014] In an embodiment, the number of the main body region and the bending region is multiple, the multiple main body regions are arranged spaced apart along the circumference of the cell hole, and a bending region is arranged between adjacent two main body regions.

[0015] In the above technical solution, when the bending region is connected with the peripheral portion, by arranging multiple main body regions and bending regions, the overcurrent area can be increased, the overcurrent capacity and heat dissipation capacity of the battery monomer are improved, and the main body region is arranged on both sides of the bending region along the circumference of the cell hole, so when the peripheral portion is connected with the bending region, the situation that the tab is loose or falls off from the current collector during the working process of the battery monomer can be reduced.

[0016] In an embodiment, the number of the peripheral portion is multiple, and the multiple peripheral portions are arranged spaced apart along the circumference of the cell hole and outside the center portion, and each bending region is electrically connected with the corresponding peripheral portion.

[0017] In the above technical solution, by arranging multiple peripheral portions spaced apart along the circumference of the cell hole, the injected electrolyte can be shunted along the circumference through the multiple peripheral portions to improve the electrolyte impregnation efficiency, thereby improving the manufacturing efficiency of the battery monomer.

[0018] In an embodiment, the bending region is bent towards the cell hole.

[0019] In the technical solution, the bending area is bent towards the winding core hole when connecting with the peripheral part, so that the contact area of the bending area with the peripheral part is increased, which facilitates the connection of the peripheral part and increases the current conduction area and reduces the contact resistance.

[0020] In an embodiment, the distance between the winding core hole and the main body area along the inner-outer direction is a first size, the size of the main body area along the inner-outer direction is a second size, and the ratio between the first size and the second size is not greater than 0.25, wherein the inner-outer direction is perpendicular to the first direction.

[0021] In the technical solution, by setting a suitable ratio, the contact area of the bending area with the peripheral part is increased, and the overcurrent capacity of the battery monomer is improved.

[0022] In an embodiment, the bending area is welded with the peripheral part.

[0023] In the technical solution, the bending area is welded with the peripheral part, which can improve the connection strength between the current collector and the tab, and the connection stability between the current collector and the tab is good, so that the current collector and the tab are less likely to be loosened or detached due to shaking, and the manufacturing efficiency of the battery monomer is improved.

[0024] In an embodiment, in the projection along the first direction, the inner contour of the main body area is adapted to the outer contour of the center part.

[0025] In the technical solution, by adapting the inner contour of the main body area to the outer contour of the center part, the main body area is less likely to be bent and folded by the center part, and the reliability of the battery monomer is improved.

[0026] In an embodiment, the inner contour of the main body area is arc-shaped, and the shape of the center part is disc-shaped, hemispherical or cylindrical.

[0027] In the technical solution, the main body area is less likely to be bent and folded by the center part, and the winding core hole is better shielded to prevent metal particles remaining when the electrolyte processes the tab from being brought into the wound core by the winding core hole.

[0028] In an embodiment, the battery monomer is a cylindrical battery.

[0029] In the technical solution, on the one hand, the cylindrical battery has a high energy density and can store more electric energy in a smaller volume; on the other hand, the cycle life of the cylindrical battery is long and is less likely to have capacity attenuation.

[0030] Another aspect of the embodiments of the present application discloses a battery comprising the battery monomer in any one of the above embodiments.

[0031] In the above technical solution, the reliability of the battery is improved, and the reliability of the corresponding battery is also improved.

[0032] In another aspect, the application provides a battery, comprising the battery cell.

[0033] In the above technical solution, the reliability of the battery is improved, and the reliability of the corresponding battery is also improved. BRIEF DESCRIPTION OF DRAWINGS

[0034] Fig. 1 is a structural schematic diagram of a battery cell according to an embodiment of the application;

[0035] Fig. 2 is a structural schematic diagram of Fig. 1 from another perspective;

[0036] Fig. 3 is a structural schematic diagram of a wound battery cell according to another embodiment of the application;

[0037] Fig. 4 is a structural schematic diagram of a battery according to another embodiment of the application;

[0038] Fig. 5 is a structural schematic diagram of a vehicle according to another embodiment of the application

[0039] The reference signs in the drawings represent the following: vehicle 1000; battery cell 100; wound battery cell 1; winding hole 1a; tab 11; bending area 11a; main body area 11b; empty area 11c; current collector 2; center part 21; peripheral part 22; first dimension A; second dimension B; battery 200; box 201; first box 201a; second box 201b; controller 300; motor 400. DETAILED DESCRIPTION

[0040] The embodiments of the technical solutions of the application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the application, and therefore only serve as examples, and cannot limit the protection scope of the application.

[0041] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments of the application, and are not intended to limit the application; the terms "include" and "have" and any variations thereof in the specification and the above drawings are intended to cover non-exclusive inclusion.

[0042] In the description of the embodiments of the present application, the technical terms "first", "second", "third" and the like are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "a plurality of" is two or more, unless otherwise explicitly specified and limited.

[0043] Reference herein to "embodiments" means that the particular features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily mutually exclusive or alternative to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0044] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connecting", "fixing" and the like should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0045] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical term "contacting" should be understood broadly, which can be direct contact or contact through an intermediate medium layer, which can be contact between two objects in contact without interaction force, or contact between two objects in contact with interaction force.

[0046] At present, new energy batteries are more and more widely used in life and industry. New energy batteries are not only applied to energy storage power supply systems such as hydroelectric, thermal, wind and solar power stations, but also widely used in electric bicycles, electric motorcycles, electric vehicles and other electric vehicles. With the continuous expansion of the application field of power batteries, the market demand is also increasing.

[0047] As part of the inventive concept of the present application, before describing the embodiments of the present application, it is necessary to analyze the related art that the metal particles remaining during the processing of the tab are easy to enter the inside of the wound core through the core hole with the electrolyte, which reduces the reliability of the battery monomer. Through reasonable analysis, the technical scheme of the embodiments of the present application is obtained.

[0048] In the related art, the battery monomer includes a winding cell and a current collector, the winding battery is formed with a winding hole, and the tab is located at the periphery of the winding hole. Metal particles remaining during processing of the tab are easy to enter the inside of the winding cell through the winding hole along with the electrolyte, causing hidden dangers.

[0049] If part of the current collector can be covered on the winding hole, the reliability of the battery monomer can be improved.

[0050] The scheme of the embodiment of the application can be applied to electric devices such as automobiles, but is not limited to this, and can also be applied to energy storage containers and the like. By dividing the current collector 2 into two parts, i.e., the central part 21 and the peripheral part 22, the peripheral part 22 is connected with the tab 11, and the central part 21 is covered on the winding hole 1a.

[0051] In the embodiment of the application, the battery monomer 100 can be a secondary battery, which refers to a battery monomer 100 that can be activated by charging after discharging to continue to be used.

[0052] In the embodiment of the application, the battery monomer 100 can be a lithium ion battery, a sodium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead storage battery, etc., and the embodiment of the application is not limited thereto.

[0053] The embodiment of the application provides a battery monomer 100, please refer to FIG. 1 to FIG. 3, the battery monomer 100 includes a shell (not shown in the figure), an electrode terminal (not shown in the figure), a winding cell 1 and a current collector 2, and the electrode terminal is arranged on the shell. The winding cell 1 is arranged in the shell, the axis direction of the winding cell 1 is the first direction, the winding cell 1 has a winding hole 1a and a tab 11. The winding cell 1 has a current collector 2 at least at one end along the first direction, the current collector 2 includes a central part 21 and a peripheral part 22, the central part 21 is connected with the peripheral part 22, the central part 21 is covered on the winding hole 1a, and the peripheral part 22 is respectively connected with the tab 11 and the electrode terminal.

[0054] The tab 11 at one end of the winding cell 1 along the first direction is a positive tab, and the tab 11 at the other end of the winding cell 1 along the first direction is a negative tab.

[0055] The shell refers to a structure for accommodating the wound cell 1 to form a certain protection to the wound cell, and to reduce the risk of the wound cell 1 being damaged by being exposed. In some embodiments, the shell can be a sealed structure or a non-sealed structure. As an example, when the shell 3 is a sealed structure, the shell 3 can play a role in protecting the electrode assembly and to some extent preventing electrolyte leakage and the like. When the shell 3 is a non-sealed structure, the shell 3 can play a role in protecting the electrode assembly, and the shell 3 and the electrode assembly can further include a sealing bag for packaging the electrode assembly and electrolyte and the like. Specifically, the sealing bag can be a bag-shaped insulating member or an aluminum plastic film.

[0056] The current collector 2 refers to a conductive element for connecting the tab 11 of the battery monomer 100 with the electrode terminal to lead out the electrical energy of the wound cell 1 through the electrode terminal.

[0057] The electrode terminal refers to an element for connecting the current collector 2 with an external circuit, for example, the electrode terminal can be a pole, the number of electrode terminals is at least two, one of the at least two electrode terminals is a positive electrode terminal, and the other of the at least two electrode terminals is a negative electrode terminal, the positive electrode terminal is connected with the peripheral portion 22 of the positive tab, and the negative electrode terminal is connected with the peripheral portion 22 of the negative tab.

[0058] The battery cell 100 includes an electrolyte, which is located in the shell, and the wound core 1 refers to a core formed by winding the positive electrode sheet, the negative electrode sheet, and the separator disposed between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet is coated with a positive electrode active material, and the part of the positive electrode sheet not coated with the positive electrode active material forms a positive electrode tab. Taking a lithium battery as an example, the positive electrode sheet is a metal foil, which can be silver surface treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc. The positive electrode active material can be at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, the present application is not limited to these materials, and other conventional materials that can be used as positive electrode active materials of the battery cell 100 can also be used. These positive electrode active materials can be used alone or in combination with two or more. Among them, examples of lithium-containing phosphates can include but are not limited to at least one of lithium iron phosphate (such as LiFePO4 (also referred to as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium manganese iron phosphate, and a composite material of lithium manganese iron phosphate and carbon. The negative electrode sheet is coated with a negative electrode active material, and the part of the negative electrode sheet not coated with the negative electrode active material forms a negative electrode tab. The negative electrode sheet can be a metal foil, which can be silver surface treated aluminum or stainless steel, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc. The separator can be a separator film, and the present application does not have a specific limitation on the type of separator film, and any known porous structure separator film with good chemical stability and mechanical stability can be selected, for example, the main material of the separator film can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride, and ceramic. The electrolyte plays a role in conducting ions between the positive and negative electrodes, and the type of electrolyte is not specifically limited and can be selected as needed. The electrolyte can be liquid, gel, or solid.

[0059] The battery cell 100 provided by the embodiment of the present application can protect the wound core 1 to some extent by arranging the wound core 1 in the shell, thereby improving the service life of the wound core 1. The current collector 2 includes a central portion 21 and a peripheral portion 22, the central portion 21 is arranged on the core hole 1a, and the peripheral portion 22 is electrically connected with the tab 11 and the electrode terminal respectively. In this way, the electrolyte can be prevented from bringing the residual metal particles during the processing of the tab 11 into the wound core 1 through the core hole 1a, thereby reducing the short circuit in the wound core 1 and the performance degradation of the battery cell 100, and improving the reliability. The wound core 1 has tabs 11 of opposite polarities on opposite sides, thereby reducing the short circuit caused by the contact between the tabs 11 of opposite polarities, and further improving the reliability of the battery cell 100.

[0060] In an embodiment, referring to FIG. 1 and FIG. 3, the tab 11 at the corresponding end of the winding core 1 in the first direction is arranged around the corresponding center portion 21, and the center portion 21 is spaced apart from the tab 11.

[0061] For example, the center portion 21 and the tab 11 can be spaced apart by at least a thickness of the tab 11.

[0062] Here, the center portion 21 is spaced apart from the tab 11, so that, on the one hand, when the center portion 21 covers the winding core hole 1a, the tab 11 is spaced apart from the center portion 21 to reduce the occurrence of the tab 11 being bent and folded, and the reliability is further improved; on the other hand, the tab 11 is spaced apart from the center portion 21, which means that the number of tabs 11 is reduced to reduce the surface density of the tab 11, so that not only the impregnation efficiency of the electrolyte can be improved, but also the exhaust rate inside the winding core 1 can be improved, and the heat dissipation performance is good.

[0063] In an embodiment, referring to FIG. 1 and FIG. 3, the tab 11 includes a main body area 11b, a bending area 11a, and a void area 11c, the bending area 11a has a height difference with the main body area 11b in the first direction, the void area 11c corresponds to the winding core hole 1a, and the peripheral portion 22 is connected to the bending area 11a.

[0064] For example, the limit position of the bending area 11a on the side of the electrode terminal in the first direction is the target position, the size of the main body area 11b in the first direction towards the electrode terminal of the corresponding end is greater than the size of the bending area 11a, so that the shapes of the two are roughly stepped, and the void area 11c is correspondingly provided with the winding core hole 1a. The peripheral portion 22 is connected to the bending area 11a and the electrode terminal of the corresponding end.

[0065] In this way, by forming the bending area 11a, the contact area with the peripheral portion 22 can be increased, facilitating the electrical connection of the peripheral portion 22 and improving the overcurrent capacity of the battery monomer 100. By making the bending area 11a have a height difference with the main body area 11b in the first direction, the layout of the center portion 21, the peripheral portion 22, the bending area 11a, the main body area 11b, and the void area 11c is more flexible, and the space is fully utilized. By forming the void area 11c, when the center portion 21 covers the winding core hole 1a, the main body area 11b and the bending area 11a are spaced apart from the center portion 21 to reduce the occurrence of the tab 11 being bent and folded.

[0066] It should be noted that the first direction can be the axis direction of the winding core 1.

[0067] It should be noted that R1 in FIG. 1 can be the first direction, and R2 can be the inside-out direction.

[0068] For example, in an embodiment, the shape of the winding core 1 after being unfolded can be a rectangle, a square, or other shapes.

[0069] In an embodiment, the bending area 11a is welded with the peripheral portion 22.

[0070] The welding manner is not limited, for example, can be laser welding, ultrasonic welding or resistance welding, etc.

[0071] In this way, by welding the bending area 11a with the peripheral portion 22, on the one hand, the connection strength between the current collector 2 and the tab 11 can be improved, the connection between the current collector 2 and the tab 11 is good in stability, and the situation of loosening or falling off between the two due to shaking can be reduced; on the other hand, the manufacturing efficiency of the battery monomer 100 can also be improved.

[0072] In an embodiment, the battery monomer 100 is a cylindrical battery. The cylindrical battery refers to a battery monomer with a cylindrical shell. On the one hand, the cylindrical battery has a high energy density and can store more electrical energy in a smaller volume; on the other hand, the cycle life of the cylindrical battery is longer and is not prone to capacity decay.

[0073] In an embodiment, please refer to FIG. 3, the bending area 11a is bent towards the winding core hole 1a. In this way, when the bending area 11a is connected with the peripheral portion 22, by bending the bending area 11a towards the winding core hole 1a, the contact area between the bending area 11a and the peripheral portion 22 can be increased, which not only facilitates the connection of the peripheral portion 22, but also increases the current conduction area and reduces the contact resistance due to the increase of the contact area.

[0074] In an embodiment, please refer to FIG. 1 and FIG. 3, the number of the main body area 11b and the bending area 11a is multiple, the multiple main body areas 11b are arranged along the circumference of the winding core hole 1a, and the bending area 11a is arranged between the adjacent two main body areas 11b.

[0075] For example, the number of the bending area 11a and the main body area 11b can be four. Each bending area 11a is formed with a main body area 11b on both sides along the circumference of the winding core hole 1a, and the size of the bending area 11a in the first direction is smaller than the size of the main body area 11b, so that the shape of the bending area 11a and the main body area 11b on both sides is approximately concave, and the peripheral portion 22 is connected to the bending area 11a in the concave shape.

[0076] Here, when the bending area 11a is connected with the peripheral portion 22, by arranging multiple main body areas 11b and bending areas 11a, the current conduction area can be increased, and the current carrying capacity and heat dissipation capacity of the battery monomer 100 can be improved, and the main body area 11b is arranged on both sides of the bending area 11a along the circumference of the winding core hole 1a, so that when the peripheral portion 22 is connected with the bending area 11a, the situation of loosening or falling off between the tab 11 and the current collector 2 in the working process of the battery monomer 100 can be reduced.

[0077] In one embodiment, referring to FIG. 1, the number of the peripheral portions 22 is multiple, and the multiple peripheral portions 22 are arranged at the outer periphery of the center portion 21 along the circumferential direction of the core hole 1a, and each of the bending zones 11a is electrically connected to the corresponding peripheral portion 22.

[0078] For example, the number of the peripheral portions 22 is four, and the four peripheral portions 22 are respectively a first peripheral portion, a second peripheral portion, a third peripheral portion, and a fourth peripheral portion, and the first peripheral portion, the second peripheral portion, the third peripheral portion, and the fourth peripheral portion can be arranged at the outer periphery of the center portion 21 along the circumferential direction of the core hole 1a at intervals of 90°, so that the shape of the current collector 2 is approximately cross-shaped, and each of the bending zones 11a is connected to the corresponding peripheral portion 22.

[0079] In this way, by arranging the multiple peripheral portions 22 at intervals along the circumferential direction of the core hole 1a, the injected electrolyte can be branched along the circumferential direction through the multiple peripheral portions 22, so as to improve the electrolyte infiltration efficiency, thereby improving the manufacturing efficiency of the battery monomer 100.

[0080] In one embodiment, referring to FIG. 2, in the projection along the first direction, the inner contour of the main body zone 11b is adapted to the outer contour of the center portion 21.

[0081] For example, the inner contour of the main body zone 11b refers to the contour of the side of the main body zone 11b close to the core hole 1a along the inner-outer direction, and the outer contour of the center portion 21 refers to the contour of the side of the center portion 21 away from the core hole 1a along the inner-outer direction.

[0082] Here, by adapting the inner contour of the main body zone 11b to the outer contour of the center portion 21, the situation that the main body zone 11b is pressed, bent, and folded by the center portion 21 can be reduced, and the reliability of the battery monomer 100 can be improved.

[0083] In one embodiment, the inner contour of the main body zone 11b is circular arc-shaped, and the shape of the center portion 21 is disc-shaped, hemispherical, or cylindrical.

[0084] For example, the inner contour of the main body zone 11b can be circular arc-shaped, and the shape of the center portion 21 can be disc-shaped. The inner contour of the tab 11 can be circular arc-shaped, and the shape of the center portion 21 can be hemispherical. The inner contour of the tab 11 can be circular arc-shaped, and the shape of the center portion 21 can be cylindrical.

[0085] In this way, not only can the situation that the main body zone 11b is pressed, bent, and folded by the center portion 21 be reduced, but also the core hole 1a can be better shielded to block the metal particles remaining when the tab 11 is processed from being brought into the wound core 1 through the core hole 1a by the electrolyte.

[0086] In an embodiment, referring to FIG. 3, the distance between the winding core hole 1a and the main body area 11b along the inner-outer direction is a first size A, the size of the main body area 11b along the inner-outer direction is a second size B, and the ratio between the first size A and the second size B is not greater than 0.25, wherein the inner-outer direction is perpendicular to the first direction.

[0087] For example, the first size A refers to the distance between the edge of the main body area 11b and the edge of the winding core hole 1a along the inner-outer direction. The second size B refers to the distance between the part of the main body area 11b closest to the winding core hole 1a and the part of the main body area 11b farthest from the winding core hole 1a. The ratio between the first size A and the second size B can be 0.05, 0.1, 0.15, 0.2, or 0.25, and the like. In this way, by setting an appropriate ratio, not only can the contact area of the bending area 11a and the surrounding part 22 be improved, but also the overcurrent capacity of the battery monomer 100 can be improved.

[0088] For example, in an embodiment, after the winding core 1 is curled, the tab 11 at the winding core hole 1a, i.e., the empty area 11c, can be cut off, so that when the center part 21 covers the winding core hole 1a, the distance between the center part 21 and the main body area 11b along the inner-outer direction is the first size A. In this way, by cutting, on the one hand, the situation that the tab 11 is folded in the direction of the winding core hole 1a can be reduced; on the other hand, the surface density of the tab 11 can be reduced, not only improving the infiltration efficiency of the electrolyte, but also increasing the exhaust efficiency to improve the heat dissipation performance.

[0089] For example, in an embodiment, after the winding core 1 is curled, three turns of the tab 11 can be cut outward from the winding core hole 1a as the center, on the one hand, reducing the situation that the tab 11 is bent and folded in the direction of the winding core hole 1a when the center part 21 covers the winding core hole 1a, and the reliability is high; on the other hand, the surface density of the tab 11 can be reduced, the infiltration efficiency of the electrolyte and the exhaust rate can be improved, and the heat dissipation effect can be improved.

[0090] Another aspect of the embodiments of the present application provides a battery 200, which includes the battery monomer 100 in any of the above embodiments. Due to the improvement of the reliability of the battery monomer 100, the reliability of the corresponding battery 200 is also improved.

[0091] In an embodiment, the number of the battery monomers 100 is at least two, and the battery 200 comprises a busbar connected to the electrode terminals of the at least two battery monomers 100. In this way, the energy density of the battery 200 can be improved. In some embodiments, referring to FIG. 4, the battery 200 comprises a box 201, the box 201 comprises a first box 201a and a second box 201b, the first box 201a and the second box 201b are buckled so that a closed space is formed inside the box 201 to accommodate the battery monomers 100 to protect the battery monomers 100. Here, closed means covered or closed, which can be sealed or unsealed. The first box 201a can be a top cover or a bottom plate.

[0092] In another aspect, the battery 200 is used in an electric device. The electric device comprises the battery 200, and the battery 200 is used to provide electric energy. Due to the improvement of the reliability of the battery 200, the reliability of the electric device is also improved.

[0093] The electric device is a device that uses electric energy as energy and realizes corresponding functions by consuming electric energy. For example, the electric device can be, but is not limited to, a mobile phone, a tablet computer, a notebook computer, an electric toy, an electric tool, an electric car, an electric vehicle, a ship, a spacecraft, etc. The electric toy can include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric plane toys, etc. The spacecraft can include airplanes, rockets, space shuttles, and spaceships, etc.

[0094] The electric device of the embodiment of the present application can comprise a device main body and a power supply device, the power supply device is used to supply power to the device main body, and the power supply device can comprise the battery 200.

[0095] The device main body refers to the main structure that consumes electric energy to realize corresponding functions. For example, the electric device can be a mobile phone, and the device main body is the part that can realize communication functions, etc., and the part that can realize communication functions, etc. is supplied with power by the battery 200. For example, the electric device can be a car, and the device main body is the part that can accommodate people and can travel on the road, and the part that can accommodate people and can travel on the road is supplied with power by the battery 200.

[0096] The power supply device refers to a device that can output electric energy. For example, the battery 200 can output electric energy.

[0097] Taking the electric device of an embodiment of the present application as a vehicle 1000 for example, referring to FIG. 5.

[0098] An embodiment of the present application provides a vehicle 1000, which can be a fuel automobile, a gas automobile or a new energy automobile. The new energy automobile can be a pure electric automobile, a hybrid automobile or a range extended automobile. The vehicle 1000 is internally provided with a battery 200, which can be arranged at the bottom, the head or the tail of the vehicle 1000. The battery 200 can be used for power supply of the vehicle 1000, for example, the battery 200 can be used as an operating power supply of the vehicle 1000. The vehicle 1000 can further include a controller 300 and a motor 400, and the controller 300 can be used to control the battery 200 to supply power to the motor 400. For example, the battery 200 can be used for the working power demand of the vehicle 1000 during starting, navigation and driving.

[0099] The battery monomer 100 provided by the embodiment of the present application, please refer to FIG. 1 to FIG. 3, the battery monomer 100 is a cylindrical battery, the battery monomer 100 includes a shell, an electrode terminal, a winding core 1 and a current collector 2, the electrode terminal is arranged in the shell, the winding core 1 is arranged in the shell, the axial direction of the winding core 1 is the first direction, the winding core 1 has a winding core hole 1a and a tab 11, the winding core 1 has a current collector 2 at least at one end along the first direction, the current collector 2 includes a center part 21 and a peripheral part 22, the center part 21 is connected with the peripheral part 22, the center part 21 is arranged on the winding core hole 1a, the tab 11 at the corresponding end of the winding core 1 along the first direction is arranged around the corresponding center part 21, the center part 21 is arranged with the tab 11, and the peripheral part 22 is electrically connected with the tab 11 and the electrode terminal respectively; the tab 111 includes a main body area 11b, a bending area 11a and an empty area 11c, the bending area 11a has a height difference with the main body area 11b along the first direction, the empty area 11c corresponds to the winding core hole 1a, and the peripheral part 22 is connected with the bending area 11a; the number of the main body area 11b and the bending area 11a is multiple, the multiple main body areas 11b are arranged at intervals along the circumferential direction of the winding core hole 1a, the bending area 11a is arranged between the adjacent two main body areas 11b, the number of the peripheral part 22 is four, the four peripheral parts 22 are arranged at intervals along the circumferential direction of the winding core hole 1a at the outer periphery of the center part 21, and each bending area 11a is welded with the corresponding peripheral part 22; in the projection along the first direction, the inner contour of the main body area 11b is matched with the outer contour of the center part 21, specifically, the inner contour of the main body area 11b is arc-shaped, and the shape of the center part 21 is disc-shaped, hemispherical or cylindrical; the interval between the winding core hole 1a and the main body area 11b along the inner and outer directions is a first size A, the size of the main body area 11b along the inner and outer directions is a second size B, and the ratio between the first size A and the second size B is not greater than 0.25.

[0100] The above embodiments are only used to illustrate the technical solutions of the present application, rather than limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the specification of the present application. Especially, as long as there is no structural conflict, each technical feature mentioned in each embodiment can be combined in any way.

Claims

1. A battery cell, characterized by, The battery cell comprises: a shell; an electrode terminal arranged in the shell; a winding cell arranged in the shell, an axis direction of the winding cell being a first direction, the winding cell having a winding core hole and a tab; a current collector, the winding cell having the current collector at least at one end along the first direction, the current collector comprising a central part and a peripheral part, the central part being connected to the peripheral part, the central part covering the winding core hole, and the peripheral part being electrically connected to the tab and the electrode terminal respectively.

2. The battery cell of claim 1, wherein, The tab at the corresponding end of the winding cell along the first direction is arranged around the corresponding central part, and the central part is spaced apart from the tab.

3. The battery cell according to claim 1 or 2, characterized in that, The tab comprises a main body region, a bending region, and a void region, the bending region having a height difference with the main body region along the first direction, and the void region corresponding to the winding core hole, and the peripheral part being connected to the bending region.

4. The battery cell of claim 3, wherein, The number of the main body regions and the number of the bending regions are both plural, the plural main body regions being arranged along a circumferential direction of the winding core hole, and the bending region being arranged between two adjacent main body regions.

5. The battery cell of claim 4, wherein, The number of the peripheral parts is plural, the plural peripheral parts being arranged along the circumferential direction of the winding core hole at an outer periphery of the central part, and each bending region being electrically connected to the corresponding peripheral part.

6. The battery cell according to claim 3 or 4, characterized in that, The bending region is bent towards the winding core hole.

7. The battery cell according to any one of claims 3 to 6, characterized in that, A distance between the winding core hole and the main body region along an inner-outer direction is a first size, a size of the main body region along the inner-outer direction is a second size, and a ratio between the first size and the second size is not greater than 0.25, wherein the inner-outer direction is perpendicular to the first direction.

8. The battery cell according to any one of claims 3 to 7, characterized in that, The bending region is welded to the peripheral part.

9. The battery cell according to any one of claims 3 to 8, characterized in that, An inner contour of the main body region and an outer contour of the central part are adapted to each other along a projection in the first direction.

10. The battery cell of claim 9, wherein, The inner contour of the main body region is a circular arc shape, and the central part has a shape of a disc, a hemisphere, or a cylinder.

11. The battery cell according to any one of claims 1 to 10, characterized in that, The battery cell is a cylindrical battery.

12. A battery, characterized by The battery comprises the battery cell according to any one of claims 1 to 11.

13. An electrical device, comprising: The battery according to claim 12 is configured to provide electric energy for the electric device.

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