Battery monomer, battery and electric device

Abstract

The utility model relates to the technical field of batteries, and provides a battery monomer, a battery and a power utilization device, the battery monomer comprises a shell, an electrode terminal, a winding battery cell and a current collector, and the electrode terminal is arranged on the shell; the winding battery cell is arranged in the shell, the axis direction of the winding battery cell is a first direction, and the winding battery cell is provided with a winding cell hole and a tab; at least one end of the winding cell along the first direction is provided with a current collector, the current collector comprises a central part and a peripheral part, the central part is connected with the peripheral part, the central part covers the winding cell hole, and the peripheral part is electrically connected with the tab and the electrode terminal respectively. The battery monomer, the battery and the electric device provided by the utility model are high in reliability.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and particularly to a battery cell, a battery and an electrical device. Background Art

[0002] 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 hydraulic power plants, thermal power plants, wind power plants and solar power plants, but also widely applied to electric vehicles such as electric bicycles, electric motorcycles and electric cars.

[0003] In related technologies, metal particles remaining on the tab can enter the wound battery core through the core hole, which is likely to cause potential hazards. Summary of the Utility Model

[0004] In view of this, embodiments of the present application are expected to provide a battery cell, a battery and an electrical device with high reliability.

[0005] To achieve the above object, the technical solution of the embodiments of the present application is realized as follows:

[0006] On the one hand, an embodiment of the present application discloses a battery cell, which includes a housing, an electrode terminal, a wound battery core and a current collector. The electrode terminal is arranged on the housing. The wound battery core is arranged in the housing, the axial direction of the wound battery core is the first direction, and the wound battery core has a core hole and tabs. At least one end of the wound battery core in the first direction has a current collector, and each end current collector includes a central part and a peripheral part. The central part connects the peripheral part, the central part covers the core hole, and the peripheral parts are respectively electrically connected to the tabs and the electrode terminal.

[0007] In the above technical solution, by arranging the wound battery core in the housing, the wound battery core can be protected to a certain extent, and the service life of the wound battery core can be improved. The current collector includes a central part and a peripheral part. The central part covers the core hole, and the peripheral parts are respectively electrically connected to the tabs and the electrode terminal. In this way, the electrolyte can be blocked from bringing the remaining metal particles during tab treatment into the wound battery core through the core hole, reducing the occurrence of short circuits inside the wound battery core and the performance degradation of the battery cell, and having high reliability. The tabs on opposite sides of the wound battery core have opposite polarities. In this way, the situation of short circuit caused by the contact of tabs with opposite polarities is reduced, so as to further improve the reliability of the battery cell.

[0008] In one embodiment, the tabs at the corresponding ends of the wound battery core in the first direction surround the corresponding central part, and the central part and the tabs are arranged at intervals.

[0009] In the above technical solution, the central part and the tab are arranged at intervals. In this way, on the one hand, when the central part covers the core hole 1a, the tab will be spaced apart from the central part to reduce the occurrence of the tab being bent and folded, and the reliability is further improved; on the other hand, the tab is spaced apart from the central part, which means a reduction in the number of tabs to reduce the surface density of the tabs. In this way, not only can the infiltration efficiency of the electrolyte be improved, but also the exhaust rate inside the wound battery cell can be increased, and the heat dissipation performance is good.

[0010] In one embodiment, the tab includes a main body area, a bending area and a clearance area. The bending area and the main body area have a height difference in the first direction. The clearance area corresponds to the core hole, and the peripheral part is connected to the bending area.

[0011] In the above technical solution, by forming the bending area, the contact area with the peripheral part can be increased, which is convenient for the peripheral part to make electrical connection and improve the over-current capacity of the battery cell. Since the main bending area and the main body area have a height difference in the first direction, the layout of the central part, the peripheral part, the bending area, the main body area and the clearance area is more flexible, making full use of the space. By forming the clearance area, when the central part covers the core hole, the main body area and the bending area will be spaced apart from the central part to reduce the occurrence of the tab being bent and folded.

[0012] In one embodiment, the number of the main body areas and the bending areas is multiple. The multiple main body areas are arranged at intervals along the circumference of the core hole, and a bending area is provided between two adjacent main body areas.

[0013] In the above technical solution, when the bending area is connected to the peripheral part, by setting multiple main body areas and bending areas, the over-current area can be increased, the over-current capacity and heat dissipation capacity of the battery cell can be improved, and the main body areas are provided on both sides of the bending area along the circumference of the core hole. In this way, when the peripheral part is connected to the bending area, the situation that the tab may become loose or fall off from the current collector during the operation of the battery cell can be reduced.

[0014] In one embodiment, the number of the peripheral parts is multiple. The multiple peripheral parts are arranged at intervals along the circumference of the core hole on the outer periphery of the central part, and each bending area is electrically connected to the corresponding peripheral part.

[0015] In the above technical solution, by arranging multiple peripheral parts at intervals along the circumference of the core hole, the injected electrolyte can be shunted along the circumference through the multiple peripheral parts to improve the electrolyte infiltration efficiency, thereby improving the manufacturing efficiency of the battery cell.

[0016] In one embodiment, the distance between the core hole and the main body area in the inner and outer direction is the first dimension, the dimension of the main body area in the inner and outer direction is the second dimension, and the ratio between the first dimension and the second dimension is not greater than 0.25, wherein the inner and outer direction is perpendicular to the first direction.

[0017] In the above technical solution, by setting an appropriate ratio, not only can the contact area between the bending area and the peripheral part be increased, but also the over-current capacity of the battery cell can be improved.

[0018] In one embodiment, the bending area is welded to the peripheral part.

[0019] In the above technical solution, by welding the bending area to the peripheral part, on the one hand, the connection strength between the current collector and the tab can be increased, the connection stability between the current collector and the tab is good, and the situation that the two become loose or fall off due to shaking can be reduced; on the other hand, the manufacturing efficiency of the battery cell can also be improved.

[0020] In one embodiment, in the projection along the first direction, the inner contour of the main body area is adapted to the outer contour of the central part.

[0021] In the above technical solution, by adapting the inner contour of the main body area to the outer contour of the central part, the situation that the main body area is bent and folded by the central part can be reduced, and the reliability of the battery cell can be improved.

[0022] In one embodiment, the inner contour of the main body area is arc-shaped, and the shape of the central part is disc-shaped, hemispherical or cylindrical.

[0023] In the above technical solution, not only can the situation that the main body area is bent and folded by the central part be reduced, but also the winding core hole can be better shielded to prevent the electrolyte from bringing the metal particles remaining during the treatment of the tab into the wound battery core through the winding core hole.

[0024] In one embodiment, the battery cell is a cylindrical battery.

[0025] In the above 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 cylindrical battery has a long cycle life and is not prone to capacity attenuation.

[0026] Another aspect of the embodiments of the present application discloses a battery, including the battery cell in any one of the above embodiments.

[0027] In the above technical solution, due to the improvement of the reliability of the battery cell, the reliability of the corresponding battery is also improved.

[0028] Another aspect of the embodiments of the present application discloses an electrical device, including the battery in the above embodiments, for providing electric energy for the electrical device.

[0029] In the above technical solution, due to the improvement of the reliability of the battery, the reliability of the corresponding electrical device is also improved. Description of the Drawings

[0030] Figure 1Schematic diagram of a battery cell provided by an embodiment of the present application;

[0031] Figure 2 is Figure 1 Schematic diagram of the structure from another perspective;

[0032] Figure 3 Schematic diagram of a wound battery core provided by another embodiment of the present application;

[0033] Figure 4 Schematic diagram of a battery provided by another embodiment of the present application;

[0034] Figure 5 Schematic diagram of a vehicle provided by yet another embodiment of the present application

[0035] Description of reference numerals

[0036] Vehicle 1000; Battery cell 100; Wound battery core 1; Core hole 1a; Tab 11; Bending area 11a; Main body area 11b; Clearance area 11c; Current collector 2; Central 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 implementation manners

[0037] The embodiments of the technical solutions of the present application will be described in detail below with reference to the drawings. The following embodiments are only used to illustrate the technical solutions of the present application more clearly, so they are only examples and cannot be used to limit the protection scope of the present application.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms "including" and "having" and any variations thereof in the specification and drawings of the present application are intended to cover non-exclusive inclusion.

[0039] In the description of the embodiments of the present application, technical terms such as "first", "second", "third", etc. are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity, specific order or primary-secondary relationship of the indicated technical features. In the description of the embodiments of the present application, "a plurality of" means more than two unless otherwise specifically defined.

[0040] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0041] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installation", "connection", "fixation" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0042] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, the technical term "contact" should be understood in a broad sense, and may be direct contact or contact through an intermediate medium layer. It may be contact with essentially no interaction force between the two contacting parties, or it may be contact with interaction force between the two contacting parties.

[0043] At present, new energy batteries are increasingly used in life and industry. New energy batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but are also widely used in electric vehicles such as electric bicycles, electric motorcycles and electric cars. With the continuous expansion of the application field of power batteries, the market demand is also constantly expanding.

[0044] As part of the creative concept of the present application, before describing the embodiments of the present application, it is necessary to understand the related art that the metal particles remaining when processing the tabs can easily enter the interior of the wound battery cell through the winding holes along with the electrolyte, thereby reducing the reliability of the battery cell. The technical solution of the embodiments of the present application is obtained through reasonable analysis.

[0045] In the related art, a battery cell includes a wound battery cell and a current collector. The wound battery cell is formed with a winding core hole, and the pole lug is located at the periphery of the winding core hole. When handling the pole lug, the residual metal particles can easily enter the wound battery cell through the winding core hole along with the electrolyte, causing hidden dangers.

[0046] If the current collector can partially cover the winding core hole, the reliability of the battery cell can be improved.

[0047] The solution of the embodiment of the present application can be, but is not limited to, applied to electrical devices such as automobiles, and can also be applied to energy storage containers, etc. By dividing the current collector 2 into two parts, namely the central part 21 and the peripheral part 22, the peripheral part 22 is connected to the tab 11, and the central part 21 covers the winding core hole 1a.

[0048] In the embodiment of the present application, the battery cell 100 can be a secondary battery, which refers to a battery cell 100 that can be activated by charging after discharging.

[0049] In the embodiment of the present application, the battery cell 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-metal hydride battery, a nickel-cadmium battery, a lead-acid battery, etc., and the embodiment of the present application does not limit this.

[0050] On the one hand, the embodiment of the present application provides a battery cell 100. Please refer to Figures 1 to 3 ., the battery cell 100 includes a housing (not shown in the figure), electrode terminals (not shown in the figure), a wound core 1 and a current collector 2. The electrode terminals are arranged on the housing. The wound core 1 is arranged inside the housing. The axial direction of the wound core 1 is the first direction. The wound core 1 has a winding core hole 1a and tabs 11. At least one end of the wound core 1 in the first direction has a current collector 2. The current collector 2 includes a central part 21 and a peripheral part 22. The central part 21 is connected to the peripheral part 22. The central part 21 covers the winding core hole 1a. The peripheral part 22 is electrically connected to the tab 11 and the electrode terminal respectively.

[0051] The tab 11 at one end of the wound core 1 in the first direction is a positive tab, and the tab 11 at the other end of the wound core 1 in the first direction is a negative tab.

[0052] The housing refers to a structure for accommodating the wound core 1 to provide a certain protection to the wound core and reduce the risk of damage to the wound core 1 when it is exposed. In some embodiments, the housing can be a sealed structure or a non-sealed structure. As an example, when the housing 3 is a sealed structure, the housing 3 can protect the electrode assembly and prevent, to a certain extent, phenomena such as electrolyte leakage. When the housing 3 is a non-sealed structure, the housing 3 can protect the electrode assembly. There may also be a sealing bag between the housing 3 and the electrode assembly, and the sealing bag is used to encapsulate the electrode assembly and electrolyte, etc. Specifically, the sealing bag can be a bag-shaped insulating part or an aluminum-plastic film.

[0053] The current collector 2 refers to a conductive element for connecting the tab 11 of the battery cell 100 to the electrode terminal, so as to lead out the electrical energy of the wound core 1 through the electrode terminal.

[0054] The electrode terminal refers to an element used to connect the current collector 2 to an external circuit. For example, the electrode terminal can be a pole column. 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 to the peripheral portion 22 of the positive tab, and the negative electrode terminal is connected to the peripheral portion 22 of the negative tab.

[0055] The battery cell 100 includes an electrolyte, which is located inside the housing. The wound electrode assembly 1 is formed by winding a positive electrode sheet, a negative electrode sheet, and a separator disposed between the positive electrode sheet and the negative electrode sheet after stacking. The positive electrode sheet is coated with a positive electrode active material, and the portion of the positive electrode sheet not coated with the positive electrode active material forms a positive tab. Taking a lithium battery as an example, the positive electrode sheet is a metal foil, and the metal foil can be aluminum or stainless steel with silver surface treatment, 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 phosphate, lithium transition metal oxide, and their respective modified compounds. However, the present application is not limited to these materials, and other conventional materials that can be used as the positive electrode active material of the battery cell 100 can also be used. These positive electrode active materials can be used alone or in combination of two or more. Among them, examples of lithium-containing phosphate can include but are not limited to lithium iron phosphate (such as LiFePO4 (which can also be abbreviated 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 portion of the negative electrode sheet not coated with the negative electrode active material forms a negative tab. The negative electrode sheet can be a metal foil, and the metal foil can be aluminum or stainless steel with silver surface treatment, stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, or titanium, etc. The separator can be a separator film. The present application has no special limitation on the type of the separator film, and any well-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, polyvinylidene fluoride, and ceramic. The electrolyte plays a role in conducting ions between the positive and negative electrodes. The present application has no specific limitation on the type of the electrolyte, and it can be selected according to requirements. The electrolyte can be liquid, gel-like, or solid.

[0056] The battery cell 100 provided by the embodiment of the present application can protect the wound battery core 1 to a certain extent by arranging the wound battery core 1 in the outer shell, thereby improving the service life of the wound battery core 1. The current collector 2 includes a central portion 21 and a peripheral portion 22. The central portion 21 covers the core hole 1a, and the peripheral portion 22 is electrically connected to the tab 11 and the electrode terminal respectively. In this way, the electrolyte can be blocked from bringing the residual metal particles during the treatment of the tab 11 into the wound battery core 1 through the core hole 1a, reducing the occurrence of short circuits inside the wound battery core 1 and the performance degradation of the battery cell 100, and improving the reliability. The tabs 11 of opposite polarities are led out from opposite sides of the wound battery core 1. In this way, the situation of short circuit caused by the contact of the tabs 11 of opposite polarities is reduced, further improving the reliability of the battery cell 100.

[0057] In one embodiment, please refer to Figure 1 and Figure 3 , the tabs 11 at the corresponding ends of the wound battery core 1 along the first direction surround the periphery of the corresponding central portion 21, and the central portion 21 and the tabs 11 are arranged at intervals.

[0058] Here, the central portion 21 and the tabs 11 are arranged at intervals. On the one hand, when the central portion 21 covers the core hole 1a, the tabs 11 will be spaced apart from the central portion 21, reducing the situation of the tabs 11 being bent and folded, and further improving the reliability; on the other hand, the tabs 11 being spaced apart from the central portion 21 means a reduction in the number of tabs 11, thereby reducing the surface density of the tabs 11. In this way, not only can the infiltration efficiency of the electrolyte be improved, but also the exhaust rate inside the wound battery core 1 can be increased, and the heat dissipation performance is good.

[0059] In one embodiment, please refer to Figure 1 and Figure 3 , the tab 11 includes a main body region 11b, a bending region 11a, and a clearance region 11c. The bending region 11a and the main body region 11b have a height difference along the first direction. The clearance region 11c corresponds to the core hole 1a, and the peripheral portion 22 is connected to the bending region 11a.

[0060] Exemplarily, the limit position of the bending region 11a along the first direction towards the side of the electrode terminal is the target position. The dimension of the main body region 11b along the first direction towards the electrode terminal near the corresponding end is larger than the dimension of the bending region 11a, so that their shapes are roughly stepped, and the clearance region 11c is correspondingly provided with a core hole 1a. The peripheral portion 22 connects the bending region 11a and the electrode terminal at the corresponding end.

[0061] In this way, by forming the bending area 11a, the contact area with the peripheral part 22 can be increased, facilitating the electrical connection of the peripheral part 22 and improving the over-current capacity of the battery cell 100. Since there is a height difference between the main bending area 11a and the main body area 11b in the first direction, the layout of the central part 21, the peripheral part 22, the bending area 11a, the main body area 11b, and the clearance area 11c is more flexible, making full use of the space. By forming the clearance area 11c, when covering the core hole 1a with the central part 21, the main body area 11b and the bending area 11a will be spaced apart from the central part 21 to reduce the occurrence of the ear 11 being bent and folded.

[0062] It should be noted that the first direction can be the axial direction of the wound battery core 1.

[0063] It should be noted that Figure 1 in it, R1 can be the first direction, and R2 can be the inner-outer direction.

[0064] Exemplarily, in one embodiment, the shape of the wound battery core 1 after being unfolded can be rectangular, square, or other shapes.

[0065] In one embodiment, the bending area 11a is welded to the peripheral part 22.

[0066] Exemplarily, the welding method is not limited. For example, it can be laser welding, ultrasonic welding, or resistance welding, etc.

[0067] In this way, by welding the bending area 11a to the peripheral part 22, on the one hand, the connection strength between the current collector 2 and the ear 11 can be improved, the connection stability between the current collector 2 and the ear 11 is good, and the situation of the two coming loose or falling off due to shaking can be reduced; on the other hand, the manufacturing efficiency of the battery cell 100 can also be improved.

[0068] In one embodiment, the battery cell 100 is a cylindrical battery. Exemplarily, a cylindrical battery refers to a battery cell with a cylindrical outer shell. 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 cylindrical battery has a long cycle life and is not prone to capacity attenuation.

[0069] In one embodiment, please refer to Figure 3 , the bending area 11a is bent towards the core hole 1a. In this way, when connecting the bending area 11a to the peripheral part 22, by bending the bending area 11a towards the core hole 1a, the contact area with the peripheral part 22 can be increased, which not only facilitates the connection of the peripheral part 22, but also can increase the current conduction area due to the increase in the contact area and reduce the contact resistance.

[0070] In one embodiment, please refer to Figure 1 and Figure 3, the number of the main body areas 11b and the bending areas 11a is multiple. The multiple main body areas 11b are arranged at intervals along the circumferential direction of the core hole 1a, and a bending area 11a is arranged between two adjacent main body areas 11b.

[0071] Exemplarily, the number of the bending areas 11a and the main body areas 11b can both be four. Each bending area 11a has main body areas 11b formed on both sides along the circumferential direction of the core hole 1a, and the dimension of the bending area 11a along the first direction is lower than that of the main body area 11b. In this way, the shapes of the bending area 11a and the main body areas 11b on both sides are roughly "concave", and the peripheral part 22 is connected to the bending area 11a located inside the "concave".

[0072] Here, when the bending area 11a is connected to the peripheral part 22, by setting multiple main body areas 11b and bending areas 11a, the current-carrying area can be increased, and the current-carrying capacity and heat dissipation capacity of the battery cell 100 can be improved. Moreover, the main body areas 11b are arranged on both sides of the bending area 11a along the circumferential direction of the core hole 1a. In this way, when the peripheral part 22 is connected to the bending area 11a, the loosening or falling off of the tab 11 and the current collector 2 that may occur during the operation of the battery cell 100 can be reduced.

[0073] In one embodiment, please refer to Figure 1 , the number of the peripheral parts 22 is multiple. The multiple peripheral parts 22 are arranged at intervals along the circumferential direction of the core hole 1a on the outer periphery of the central part 21, and each bending area 11a is electrically connected to the corresponding peripheral part 22.

[0074] Exemplarily, the number of the peripheral parts 22 is four. The four peripheral parts 22 are arranged at intervals of 90° along the circumferential direction of the core hole 1a on the outer periphery of the central part 21, so that the shape of the current collector 2 is roughly cross-shaped, and each bending area 11a is connected to the corresponding peripheral part 22.

[0075] In this way, by arranging multiple peripheral parts 22 at intervals along the circumferential direction of the core hole 1a, the injected electrolyte can be shunted along the circumferential direction through the multiple peripheral parts 22 to improve the electrolyte infiltration efficiency, thereby improving the manufacturing efficiency of the battery cell 100.

[0076] In one embodiment, please refer to Figure 2 , in the projection along the first direction, the inner contour of the main body area 11b is adapted to the outer contour of the central part 21.

[0077] Exemplarily, the inner contour of the main body area 11b refers to the contour on the side of the main body area 11b close to the core hole 1a along the inner and outer direction, and the outer contour of the central part 21 refers to the contour on the side of the central part 21 away from the core hole 1a along the inner and outer direction.

[0078] Here, by adapting the inner contour of the main body region 11b to the outer contour of the central portion 21, the situation where the main body region 11b is bent and folded by the central portion 21 can be reduced, improving the reliability of the battery cell 100.

[0079] In one embodiment, the inner contour of the main body region 11b is arc-shaped, and the shape of the central portion 21 is disc-shaped, hemispherical or cylindrical.

[0080] Exemplarily, the inner contour of the main body region 11b can be arc-shaped, and the shape of the central portion 21 can be disc-shaped. The inner contour of the tab 11 can be arc-shaped, and the shape of the central portion 21 can be hemispherical. The inner contour of the tab 11 can be arc-shaped, and the shape of the central portion 21 can be cylindrical.

[0081] In this way, not only can the situation where the main body region 11b is bent and folded by the central portion 21 be reduced, but also the winding core hole 1a can be better shielded to prevent the electrolyte from bringing the metal particles remaining during the treatment of the tab 11 into the wound battery core 1 through the winding core hole 1a.

[0082] In one embodiment, please refer to Figure 3 , the distance between the winding core hole 1a and the main body region 11b in the inner and outer directions is the first dimension A, the dimension of the main body region 11b in the inner and outer directions is the second dimension B, and the ratio between the first dimension A and the second dimension B is not greater than 0.25, where the inner and outer directions are perpendicular to the first direction.

[0083] Exemplarily, the first dimension A refers to the distance between the edge of the main body region 11b and the edge of the winding core hole 1a in the inner and outer directions. The second dimension B refers to the distance between the part of the main body region 11b closest to the winding core hole 1a and the part of the main body region 11b farthest from the winding core hole 1a. The ratio between the first dimension A and the second dimension B can be 0.05, 0.1, 0.15, 0.2 or 0.25, etc. In this way, by setting an appropriate ratio, not only can the contact area between the bending region 11a and the surrounding portion 22 be increased, but also the overcurrent capacity of the battery cell 100 can be improved.

[0084] Exemplarily, in one embodiment, after the wound battery core 1 is curled, the tab 11 at the winding core hole 1a, i.e., the clearance region 11c, can be cut off so that when the central portion 21 shields the winding core hole 1a, the distance between the central portion 21 and the main body region 11b in the inner and outer directions is the first dimension A. In this way, by the cutting method, on the one hand, the situation where the tab 11 is folded toward 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.

[0085] Exemplarily, in one embodiment, after the winding battery cell 1 is wound, the tab 11 can be cut three circles outward with the core hole 1a of the core as the center. On the one hand, it reduces the situation that the tab 11 bends and turns towards the core hole 1a when the central part 21 covers the core hole 1a, and has high reliability; on the other hand, it can reduce the surface density of the tab 11, improve the infiltration efficiency of the electrolyte and the exhaust rate, and enhance the heat dissipation effect.

[0086] On the other hand, a battery 200 provided by an embodiment of the present application includes the battery cell 100 in any one of the above embodiments. Due to the improvement of the reliability of the battery cell 100, the reliability of the corresponding battery 200 is also improved.

[0087] In one embodiment, the number of battery cells 100 is at least two, and the battery 200 includes a bus bar, and the bus bar connects the electrode terminals of at least two battery cells 100. In this way, the energy density of the battery 200 can be improved. In some embodiments, please refer to Figure 4 , the battery 200 includes a box body 201, the box body 201 includes a first box body 201a and a second box body 201b, and the first box body 201a and the second box body 201b are buckled, so that a closed space is formed inside the box body 201 to accommodate the battery cell 100 to protect the battery cell 100. The "closed" here means covering or closing, which can be sealed or non-sealed. The first box body 201a can be a top cover or a bottom plate.

[0088] On yet another aspect, an electrical device provided by an embodiment of the present application includes the battery 200 in the above embodiment, and the battery 200 is used to provide electrical energy. Due to the improvement of the reliability of the battery 200, the reliability of the corresponding electrical device is also improved.

[0089] An electrical device is a device that uses electrical energy as an energy source and realizes corresponding functions by consuming electrical energy. Exemplarily, the electrical device can be, but is not limited to, a mobile phone, a tablet computer, a laptop computer, an electric toy, an electric tool, a battery car, an electric vehicle, a ship, a spacecraft, etc. Among them, the electric toy can include a fixed or mobile electric toy, for example, a game console, an electric vehicle toy, an electric ship toy, an electric aircraft toy, etc., and the spacecraft can include an airplane, a rocket, a space shuttle, a spaceship, etc.

[0090] For the electrical device of the embodiment of the present application, the electrical device may include a device main body and a power supply device, and the power supply device is used to supply power to the device main body, and the power supply device may include the battery 200.

[0091] The device main body refers to the main structure that consumes electrical energy to achieve corresponding functions. For example, the electrical device can be a mobile phone, and the device main body is the part that can achieve functions such as communication, and the battery 200 supplies power to the part that can achieve functions such as communication. For example, the electrical device can be a car, and the device main body is the part that can be ridden by people and can travel on the road, and the battery 200 supplies power to the part that can be ridden by people and can travel on the road.

[0092] The power supply device refers to a device that can output electrical energy. Exemplarily, electrical energy can be output through the battery 200.

[0093] Taking the electrical device of an embodiment of the present application as the vehicle 1000 as an example for illustration, please refer to Figure 5 .

[0094] The vehicle 1000 provided by an embodiment of the present application can be a fuel vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid vehicle or an extended-range vehicle, etc. The battery 200 is arranged inside the vehicle 1000, and the battery 200 can be arranged at the bottom, head or 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 the operating power supply of the vehicle 1000. The vehicle 1000 can also 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 consumption requirements during the start, navigation and driving of the vehicle 1000.

[0095] The battery cell 100 provided by the embodiment of the present application, please refer to Figures 1 to 3, the battery cell 100 is a cylindrical battery. The battery cell 100 includes a housing, electrode terminals, a wound electrode core 1, and a current collector 2. The electrode terminals are provided on the housing. The wound electrode core 1 is disposed within the housing. The axial direction of the wound electrode core 1 is the first direction. The wound electrode core 1 has a core hole 1a and tabs 11. At least one end of the wound electrode core 1 in the first direction has a current collector 2. The current collector 2 includes a central portion 21 and a peripheral portion 22. The central portion 21 connects the peripheral portion 22. The central portion 21 covers the core hole 1a. The tabs 11 at the corresponding end of the wound electrode core 1 in the first direction surround the corresponding central portion 21. The central portion 21 and the tabs 11 are arranged at intervals. The peripheral portion 22 is electrically connected to the tabs 11 and the electrode terminals respectively; the tab 111 includes a main body region 11b, a bent region 11a, and a clearance region 11c. The bent region 11a and the main body region 11b have a height difference in the first direction. The clearance region 11c corresponds to the core hole 1a. The peripheral portion 22 is connected to the bent region 11a; the number of the main body regions 11b and the bent regions 11a are both multiple. The multiple main body regions 11b are arranged at intervals along the circumferential direction of the core hole 1a. A bent region 11a is provided between two adjacent main body regions 11b. The number of the peripheral portions 22 is four. The four peripheral portions 22 are arranged at intervals along the circumferential direction of the core hole 1a on the outer periphery of the central portion 21. Each bent region 11a is welded to the corresponding peripheral portion 22; in the projection along the first direction, the inner contour of the main body region 11b is adapted to the outer contour of the central portion 21. Specifically, the inner contour of the main body region 11b is arc-shaped. The shape of the central portion 21 is disc-shaped, hemispherical, or cylindrical; the distance between the core hole 1a and the main body region 11b in the inner and outer direction is the first dimension A. The dimension of the main body region 11b in the inner and outer direction is the second dimension B. The ratio between the first dimension A and the second dimension B is not greater than 0.25.

[0096] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some 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 all be covered by the scope of the description of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way.

Claims

1. A battery cell, characterized in that, Comprising: A housing; Electrode terminals, disposed on the housing; A wound battery cell, disposed within the housing, the axis direction of the wound battery cell being a first direction, the wound battery cell having a core hole and tabs; A current collector, at least one end of the wound battery cell in the first direction having the current collector, the current collector including a central portion and a peripheral portion, the central portion connecting the peripheral portion, the central portion covering the core hole, and the peripheral portions being electrically connected to the tabs and the electrode terminals respectively.

2. The battery cell according to claim 1, characterized in that, The tabs at the corresponding ends of the wound battery cell in the first direction surround the corresponding central portion, and the central portion and the tabs are arranged at intervals.

3. The battery cell according to claim 1, wherein The tab includes a main body region, a bent region, and a clearance region, the bent region having a height difference from the main body region in the first direction, the clearance region corresponding to the core hole, and the peripheral portion being connected to the bent region.

4. The battery cell according to claim 3, characterized in that, The number of the main body regions and the bent regions are both multiple, the multiple main body regions are arranged at intervals along the circumferential direction of the core hole, and the bent regions are provided between adjacent two main body regions.

5. The battery cell according to claim 4, wherein The number of the peripheral portions is multiple, the multiple peripheral portions are arranged at intervals along the circumferential direction of the core hole on the outer periphery of the central portion, and each bent region is electrically connected to the corresponding peripheral portion.

6. The battery cell according to claim 3, characterized in that, The distance between the core hole and the main body region in the inner and outer direction is a first dimension, the dimension of the main body region in the inner and outer direction is a second dimension, and the ratio between the first dimension and the second dimension is not greater than 0.25, wherein the inner and outer direction is perpendicular to the first direction.

7. The battery cell according to claim 3, characterized in that The bent region and the peripheral portion are welded.

8. The battery cell according to claim 3, characterized in that, In the projection along the first direction, the inner contour of the main body region is adapted to the outer contour of the central portion.

9. The battery cell according to claim 8, wherein The inner contour of the main body region is arc-shaped, and the shape of the central portion is disc-shaped, hemispherical or cylindrical.

10. The battery cell according to claim 1, characterized in that, The battery cell is a cylindrical battery.

11. A battery, characterized in that, Comprising the battery cell according to any one of claims 1 to 10.

12. An electrical device, characterized in that, Comprising the battery according to claim 11, for providing electrical energy for the electrical device.

Images