Electrode piece, electrode assembly, battery cell, battery pack and electric equipment

Abstract

The utility model provides a pole piece, an electrode assembly, a battery cell, a battery pack and electric equipment, and relates to the technical field of batteries. The pole piece comprises a pole piece body and a pole lug, in the first direction, the pole piece body is provided with a first side edge and a second side edge which are oppositely arranged; the tabs comprise a first tab and a second tab, the first tab is arranged on the first side edge, and the second tab is arranged on the second side edge. According to the pole piece, the tabs are arranged on the two side edges, located in the first direction, of the pole piece body, the total area of the tabs of the pole piece can be increased, so that conduction paths of electrons on the tabs are increased, and the current collection area of the pole piece can be increased. Therefore, the current collecting capacity of the pole piece is improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a pole piece, an electrode assembly, a battery cell, a battery pack and an electrical device. Background Art

[0002] In the related art, a battery cell includes a shell and an electrode assembly arranged in the shell. The electrode assembly includes a positive electrode sheet, a separator and a negative electrode sheet that are stacked and wound in sequence. In order to achieve the output of the positive and negative electrodes of the battery cell on the same side of the battery cell, the shell of the battery cell is usually used as the output electrode of the negative electrode. At the same time, the installation position for installing the pole is insulated and isolated on the top cover sheet of the shell by a seal. The pole is set in this installation position as the output pole of the positive pole. In this structure for outputting positive and negative electrodes on the same side, a positive electrode ear is provided at one end of the positive electrode sheet close to the top cover sheet, and a negative electrode ear is provided at one end of the negative electrode sheet close to the top cover sheet. The negative electrode ear is electrically connected to the shell, and the positive electrode ear is connected to the pole, so that the positive and negative electrodes of the battery cell are respectively led out.

[0003] In this solution, although the current collecting capacity of the electrode basically meets the application requirements of the battery cell, there is still room for improvement in the current collecting capacity of the electrode. Utility Model Content

[0004] The embodiments of the present application provide a pole piece, an electrode assembly, a battery cell, a battery pack, and an electrical device, which can improve the current collecting capacity of the pole piece.

[0005] In a first aspect, an embodiment of the present application provides a pole piece, which includes a pole piece body and a pole ear; in a first direction, the pole piece body has a first side and a second side that are relatively arranged; the pole ear includes a first pole ear and a second pole ear, the first pole ear is arranged on the first side, and the second pole ear is arranged on the second side.

[0006] In one embodiment, in the second direction, the pole piece body has a pole piece head end and a pole piece tail end; in the second direction, the second pole tab is arranged farther away from the pole piece head end than the first pole tab.

[0007] In one embodiment, in the second direction, the second pole tab has a second pole tab head end close to the pole piece head end, and the second pole tab head end and the pole piece head end are spaced apart.

[0008] In one embodiment, along the second direction, the distance between the second tab tip and the pole piece tip is L 12头 , the length of the pole piece body is L 10 , meet: 7% L 10 ≤L 12头 ≤20% L 10 .

[0009] In one embodiment, along the second direction, the length of the second tab is L 12耳, meet: 60% L 10 ≤L 12耳 ≤80% L 10 .

[0010] In one embodiment, along the second direction, the distance between the second tab tip and the pole piece tip is L 12头 , the length of the pole piece body is L 10 , meet: 30% L 10 ≤L 12头 ≤40% L 10 .

[0011] In one embodiment, along the second direction, the length of the second tab is L 12耳 , satisfying: L 12耳 =35%L 10 ~60% L 10 .

[0012] In one embodiment, along the first direction, the first electrode tab and the second electrode tab are at least partially disposed opposite to each other.

[0013] In one embodiment, along the first direction, the ends of the first and second tabs that are close to each other are arranged opposite to each other, the end of the first tab away from the second tab is staggered with the second tab, and the end of the second tab away from the first tab is staggered with the first tab.

[0014] In one embodiment, the electrode has a positive polarity.

[0015] In one embodiment, in the second direction, the second pole tab has a second pole tab tail end close to the pole piece tail end, and the second pole tab tail end and the pole piece tail end are spaced apart.

[0016] In one embodiment, along the second direction, the distance between the tail end of the second tab and the tail end of the pole piece is L 12尾 , the length of the pole piece body is L 10 , satisfying: 0<L 12尾 ≤33% L 10 .

[0017] In one embodiment, in the second direction, the first pole tab has a first pole tab head end close to the pole piece head end and a first pole tab tail end close to the pole piece tail end; along the second direction, the first pole tab tail end and the pole piece tail end are spaced apart, and / or, along the second direction, the first pole tab head end and the pole piece head end are spaced apart.

[0018] In one embodiment, along the second direction, the distance between the tail end of the first tab and the tail end of the pole piece is L 11尾 , the length of the pole piece body is L 10 , satisfying: L 11尾 =60% L 10~78% L 10 .

[0019] In one embodiment, along the second direction, the distance between the first tab tip and the pole piece tip is L 11头 , the length of the pole piece body is L 10 , satisfying: L 11头 =7% L 10 ~20% L 10 .

[0020] In one embodiment, along the second direction, the length of the first tab is L 11耳 , the length of the pole piece body is L 10 , satisfying: L 11耳 =15% L 10 ~20% L 10 .

[0021] In one embodiment, in the second direction, the pole piece body has a pole piece head end and a pole piece tail end; in the second direction, the second pole tab is arranged closer to the pole piece head end than the first pole tab.

[0022] In one embodiment, in the second direction, the second pole tab has a second pole tab head end close to the pole piece head end, and the second pole tab head end and the pole piece head end are spaced apart.

[0023] In one embodiment, along the second direction, the distance between the second tab tip and the pole piece tip is L 22头 , the length of the pole piece body is L 20 , satisfying: L 22头 =7% L 20 ~20% L 20 .

[0024] In one embodiment, along the second direction, the second pole tab has a second pole tab tail end close to the pole piece tail end, and the second pole tab tail end and the pole piece tail end are spaced apart.

[0025] In one embodiment, along the second direction, there is a distance L between the tail end of the second tab and the tail end of the pole piece. 22尾 , the length of the pole piece body is L 20 , satisfying: L 22尾 =60L 20 ~78% L 20 .

[0026] In one embodiment, along the second direction, the length of the second tab is L 22耳 , the length of the pole piece body is L 20 , satisfying: L 22耳 =15% L 20 ~20% L 20 .

[0027] In one embodiment, in the second direction, the first pole tab has a first pole tab head end close to the pole piece head end and a first pole tab tail end close to the pole piece tail end; along the second direction, the first pole tab tail end and the pole piece tail end are spaced apart, and / or, along the second direction, the first pole tab head end and the pole piece head end are spaced apart.

[0028] In one embodiment, along the second direction, the distance between the first tab tip and the pole piece tip is L 21头 , the length of the pole piece body is L 20 , meet: 40% L 20 ≤L 21头 ≤50% L 20 .

[0029] In one embodiment, along the second direction, the distance between the tail end of the first tab and the tail end of the pole piece is L 21尾 , the length of the pole piece body is L 20 , satisfying: 0<L 21尾 ≤30% L 20 .

[0030] In one embodiment, along the second direction, the length of the first tab is L 21耳 , the length of the pole piece body is L 20 , meet: 30% L 20 ≤L 21耳 ≤50% L 20 .

[0031] In one embodiment, along the second direction, the first electrode tab and the second electrode tab are spaced apart.

[0032] In one embodiment, the electrode has a negative polarity.

[0033] In one embodiment, the electrode includes a coating area coated with an active material and a non-coating area not coated with the active material. The electrode body is arranged in the coating area, and the electrode tab is arranged in the non-coating area.

[0034] In one embodiment, the tab is a die-cut tab.

[0035] In one embodiment, the die-cutting width of the tab is W, which satisfies 2 mm ≤ W ≤ 6 mm.

[0036] In one embodiment, the die-cutting angle of the tab is α, which satisfies 55°≤α≤85°.

[0037] In one embodiment, the die-cutting height of the tab is H, which satisfies: 5 mm ≤ H ≤ 7.5 mm.

[0038] In a second aspect, an embodiment of the present application provides an electrode assembly, which includes the aforementioned electrode piece.

[0039] In a third aspect, an embodiment of the present application provides a battery cell comprising the aforementioned electrode assembly.

[0040] In a fourth aspect, an embodiment of the present application provides a battery pack, which includes a battery box and the aforementioned battery cell; the battery box has a receiving cavity; there are multiple battery cells, and the multiple battery cells are arranged in the receiving cavity.

[0041] In a fifth aspect, an embodiment of the present application provides an electrical device, which includes the aforementioned battery cell or battery pack, and the battery cell or battery pack provides power for the electrical device.

[0042] Beneficial effects of the embodiments of the present application:

[0043] In the embodiment of the present application, by providing tabs on both sides of the pole piece body in the first direction, the total tab area of the pole piece can be increased, thereby increasing the conduction paths of electrons on the tabs and thus increasing the current collecting area of the pole piece. In this way, the current collecting capacity of the pole piece is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0045] Figure 1 Schematic diagram of the structure of the pole piece provided in the embodiment of the present application;

[0046] Figure 2 This is a schematic structural diagram of another electrode provided in an embodiment of the present application;

[0047] Figure 3 1 is a schematic structural diagram of another electrode provided in an embodiment of the present application;

[0048] Figure 4 is a cross-sectional view of a pole piece rolled into a winding core according to an embodiment of the present application;

[0049] Figure 5 Schematic diagram of the coating area and the non-coating area provided in the embodiments of the present application;

[0050] Figure 6 Schematic diagram of the structure of the tab provided in the embodiment of the present application;

[0051] Figure 7 is a schematic structural diagram of an electrode assembly provided in an embodiment of the present application;

[0052] Figure 8is a schematic structural diagram of a battery cell provided in an embodiment of the present application;

[0053] Figure 9 is a schematic structural diagram of a battery pack provided in an embodiment of the present application;

[0054] Figure 10 It is a structural diagram of the electrical equipment provided in the embodiment of the present application.

[0055] Description of reference numerals:

[0056] 001-pole piece;

[0057] 011-pole body; 111-pole head; 112-pole tail; 113-first side; 114-second side;

[0058] 012-first tab; 121-first tab head end; 122-first tab tail end;

[0059] 013-second tab; 131-second tab head end; 132-second tab tail end;

[0060] 014-ear;

[0061] 015-coating area; 016-non-coating area;

[0062] 002-electrode assembly;

[0063] 003-battery cell; 031-housing; 032-cover;

[0064] 004-battery pack; 041-battery box;

[0065] 005-Electrical equipment; DETAILED DESCRIPTION

[0066] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0067] Furthermore, it should be understood that the specific embodiments described herein are intended only to illustrate and explain the present application and are not intended to limit the present application. In this application, unless otherwise indicated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in actual use or operation, specifically the directions of the drawings in the accompanying drawings; whereas "inner" and "outer" refer to the outline of the device.

[0068] The terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the specified features. In the description of this application, "plurality" means two or more, unless otherwise specifically specified.

[0069] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections, electrical connections, or mutual communication; they can refer to direct connections or indirect connections through an intermediate medium; they can refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0070] The terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0071] In the description of the embodiments of this application, words such as "example" or "for example" are used to indicate an example, illustration, or description. Any embodiment or design described as "for example" or "for example" in the embodiments of this application is not to be construed as being preferred or having more advantages than another embodiment or design. The use of words such as "example" or "for example" is intended to clearly present relative concepts.

[0072] See also Figure 1 or Figure 2 or Figure 3 , Figure 1 This is a schematic structural diagram of the pole piece 001 provided in an embodiment of the present application. Figure 2 This is a structural diagram of another electrode 001 provided in an embodiment of the present application. Figure 3Schematic diagram of the structure of another electrode 001 provided in an embodiment of the present application. An embodiment of the present application provides a electrode 001. The electrode 001 includes a electrode body 011 and a electrode tab 014. In a first direction, the electrode body 011 has a first side 113 and a second side 114 that are oppositely disposed. The electrode tab 014 includes a first electrode tab 012 and a second electrode tab 013. The first electrode tab 012 is disposed on the first side 113, and the second electrode tab 013 is disposed on the second side 114.

[0073] It can be understood that the first direction is the width direction of the pole piece 001 , and accordingly, the pole tabs 014 are arranged on both sides of the width direction of the pole piece body 011 .

[0074] The electrode 001 includes a current collector and an active material layer disposed on the current collector. The current collector may include an active material region and a hollow foil region, wherein the active material layer is disposed in the active material region and the hollow foil region is used to form the electrode tab 014.

[0075] In this embodiment, by providing tabs 014 on both sides of the pole piece body 011 in the first direction, the total tab area of the pole piece 001 can be increased, thereby increasing the conduction paths of electrons on the tabs 014 and thereby increasing the current collecting area of the pole piece 001. Thus, the current collecting capacity of the pole piece 001 is improved.

[0076] In addition, by increasing the conduction paths of electrons on the tab 014, the internal resistance of the battery cell 003 can be reduced, thereby improving the current conduction efficiency of the battery cell 003, thereby enabling the battery cell 003 to have a higher charge and discharge speed, and reducing energy loss and temperature rise during the battery charge and discharge process, thereby improving the efficiency and performance of the battery.

[0077] See also Figure 1 or Figure 2 In one embodiment, in the second direction, the pole piece body 011 has a pole piece head end 111 and a pole piece tail end 112. In the second direction, the second pole tab 013 is arranged farther away from the pole piece head end 111 than the first pole tab 012.

[0078] It can be understood that the pole piece head end 111 is the end of the pole piece 001 close to the center of the core after the pole piece 001 is wound into a core, and the pole piece tail end 112 is the end located at the outer periphery of the core.

[0079] Typically, the first electrode tab 012 of the positive electrode is located on the first side 113 near the electrode head end 111, and the second electrode tab 013 is located on the second side 114 near the electrode tail end 112. Therefore, in this embodiment, the electrode 001 in which "the second electrode tab 013 is located farther away from the electrode head end 111 than the first electrode tab 012" is typically a electrode 001 with positive polarity.

[0080] Furthermore, the first pole tab 012 is arranged at a position on the first side 113 close to the pole piece head end 111, and the second pole tab 013 is arranged at a position on the second side 114 away from the pole piece head end 111. Along the width direction of the pole piece body 011, the end of the first pole tab 012 away from the pole piece head end 111 and the end of the second pole tab 013 close to the pole piece head end 111 can be arranged relative to each other, or the first pole tab 012 and the second pole tab 013 can be completely staggered.

[0081] In this embodiment, through the above-mentioned setting, the first pole ear 012 can mainly collect current in the area close to the head end 111 of the pole piece, and the second pole ear 013 can mainly collect current in the area close to the tail end 112 of the pole piece, so that the first pole ear 012 and the second pole ear 013 can take into account the current collection in the length direction of the entire pole piece 001, thereby shortening the current collection path of the pole piece 001 and reducing the internal resistance of the battery cell 003.

[0082] See also Figure 1 or Figure 2 In one embodiment, in the second direction, the second tab 013 has a second tab head end 131 close to the pole piece head end 111. The second tab head end 131 and the pole piece head end 111 are spaced apart.

[0083] It's understandable that after the electrode sheet 001 is wound into a core, the tabs 014 are parallel to the core's axis, occupying a relatively large height, which negatively impacts the energy density of the battery cell 003. For this reason, the tabs 014 near the core's center are typically bent toward the center to reduce the space they occupy. Directly bending the tabs 014, however, not only results in a higher stack height after bending, but also poorly flattened stacks, hindering welding between the tabs 014 and the current collector.

[0084] Based on this, in this embodiment, by spacing the second tab tip 131 from the electrode sheet tip 111, a groove is formed on the end face of the rolled core formed by the electrode sheet 001, near the center hole, to allow the bent second tab 013 to be poured into the groove. This not only reduces the stacking height of the bent second tabs 013, but also improves the flatness of the stacked second tabs 013, thereby improving the ease of welding the second tabs 013 to the current collecting plate.

[0085] In addition, the above arrangement can also prevent the second electrode tab 013 near the electrode head end 111 from blocking the central hole of the winding core after bending, thereby improving the smoothness of the electrolyte flowing into the central hole and further ensuring the wetting efficiency of the winding core.

[0086] See also Figure 1 In one embodiment, along the second direction, the distance between the second tab end 131 and the pole piece end 111 is L12头 The length of the pole piece body 011 is L 10 , meet: 7% L 10 ≤L 12头 ≤20%L 10 .

[0087] Understandable, L 12头 Including but not limited to 7% L 10 , 8.6% L 10 , 9.1% L 10 , 10% L 10 、13.6%L 10 、15.6% L 10 、18.7% L 10 , 19% L 10 , 20% L 10 .

[0088] For example:

[0089] L 10 When L is 4800mm, 12头 It can be 336mm to 960mm, for example, 336mm, 400mm, 500mm, 600mm, 753mm, 800mm, 880mm, 900mm, 960mm;

[0090] L 10 When L is 5000mm, 12头 It can be 350mm to 1000mm, for example, 350mm, 400mm, 500mm, 600mm, 753mm, 800mm, 880mm, 960mm, 1000mm;

[0091] L 10 When L is 6000mm, 12头 It can be 420mm to 1200mm, for example, 420mm, 463mm, 500mm, 600mm, 753mm, 800mm, 880mm, 960mm, 1200mm;

[0092] L 10 When L is 6200mm, 12头 It can be 434mm to 1240mm, for example, 434mm, 480mm, 500mm, 600mm, 753mm, 880mm, 980mm, 1060mm, and 1240mm.

[0093] In this embodiment, through the above definition, on the one hand, the spacing L can be avoided 12头Too small will cause the second tab 013 to be stacked too high at the center of the winding core after being bent, so as to control the stacking height of the second tab 013 after being bent and improve the flatness of the stacking of the second tab 013; on the other hand, it can avoid the spacing L 12头 Too large affects the length of the second electrode tab 013 , thereby ensuring the current collecting area of the second electrode tab 013 and further ensuring the current collecting capacity of the electrode piece 001 .

[0094] See also Figure 1 In one embodiment, along the second direction, the length of the second tab 013 is L 12耳 , meet: 60% L 10 ≤L 12耳 ≤80% L 10 .

[0095] It is understood that the electrode assembly includes two electrode sheets 001 with opposite polarities: a positive electrode sheet and a negative electrode sheet. When the electrode sheet 001 of this embodiment is wound together with another electrode sheet 001 having only the electrode tab 014 on the first side 113 and no electrode tab 014 on the second side 114 to form an electrode assembly, the second electrode tab 013 of the electrode sheet 001 of this embodiment can be set longer.

[0096] Among them, L 12耳 Including but not limited to 60% L 10 , 63% L 10 , 65.2% L 10 , 68% L 10 , 70% L 10 , 72% L 10 , 76.4% L 10 , 79% L 10 , 80% L 10 .

[0097] For example:

[0098] L 10 When L is 4800mm, 12耳 It can be 2880mm to 3840mm, for example, 2880mm, 3000mm, 3212mm, 3340mm, 3553mm, 3680mm, 3780mm, 3802mm, 3840mm;

[0099] L 10 When L is 5000mm, 12耳 It can be 3000mm to 4000mm, for example, 3000mm, 3400mm, 3500mm, 3600mm, 3753mm, 3800mm, 3880mm, 3960mm, 4000mm;

[0100] L10 When L is 6000mm, 12耳 It can be 3600mm to 4800mm, for example, 3600mm, 3700mm, 3800mm, 3960mm, 4000mm, 4180mm, 4368mm, 4760mm, 4800mm;

[0101] L 10 When L is 6200mm, 12耳 It can be 3720mm to 4960mm, for example, 3720mm, 4000mm, 4200mm, 4350mm, 4653mm, 4780mm, 4880mm, 4900mm, and 4960mm.

[0102] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the length of the second pole tab 013 being too large, which would result in a smaller spacing between the second pole tab head end 131 and the pole piece head end 111, thereby facilitating the control of the stacking height and stacking flatness of the second pole tab 013 after bending; on the other hand, it is possible to avoid the length of the second pole tab 013 being too small, which would affect the area of the second pole tab 013.

[0103] See also Figure 2 In one embodiment, along the second direction, the distance between the second tab end 131 and the pole piece end 111 is L 12头 The length of the pole piece body 011 is L 10 , meet: 30% L 10 ≤L 12头 ≤40%L 10 .

[0104] Among them, L 12头 Including but not limited to 30% L 10 , 33% L 10 、35.2% L 10 、36% L 10 、37.1%L 10 , 38.2% L 10 、39.6% L 10 、39.9% L 10 , 40% L 10 .

[0105] For example:

[0106] L 10 When L is 4800mm, 12头 It can be 1440mm to 1920mm, for example, 1440mm, 1490mm, 1500mm, 1600mm, 1753mm, 1800mm, 1880mm, 1900mm, 1920mm;

[0107] L 10 When L is 5000mm, 12头 It can be 1500mm to 2000mm, for example, 1500mm, 1540mm, 1650mm, 1660mm, 1775mm, 1800mm, 1880mm, 1960mm, 2000mm;

[0108] L 10 When L is 6000mm, 12头 It can be 1800mm to 2400mm, for example, 1800mm, 1830mm, 1950mm, 2060mm, 2175mm, 2280mm, 2288mm, 2396mm, 2400mm;

[0109] L 10 When L is 6200mm, 12头 It can be 1860mm to 2480mm, for example, 1860mm, 1948mm, 2050mm, 2160mm, 22753mm, 2388mm, 2400mm, 2460mm, and 2480mm.

[0110] It can be understood that the electrode assembly includes two electrode pieces 001 with opposite polarities. When the electrode piece 001 of this embodiment is wound together with another electrode piece 001 having electrode tabs 014 on both the first side 113 and the second side 114 to form an electrode assembly, in order to ensure that the second electrode tab 013 of the other electrode piece 001 has sufficient current collecting area, it is necessary to control the distance between the second electrode tab tip 131 of this embodiment and the electrode piece tip 111 to avoid the distance being too small and affecting the arrangement of the second electrode tab 013 of the other electrode piece 001.

[0111] Based on this, in this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the spacing between the second pole tab head end 131 and the pole piece head end 111 being too large, which would cause the length of the second pole tab 013 to be too small, so that the length of the second pole tab 013 can meet the current collecting requirements of the pole piece 001 and can help reduce the internal resistance of the battery cell; on the other hand, it is possible to avoid the spacing between the second pole tab head end 131 and the pole piece head end 111 being too small, which would affect the current collecting area of the second pole tab 013 of the other pole piece 001 that cooperates with it.

[0112] See also Figure 2 In one embodiment, along the second direction, the length of the second tab 013 is L 12耳 , satisfying: L 12耳 =35% L 10 ~60% L 10 .

[0113] Among them, L12耳 Including but not limited to 35% L 10 、38% L 10 , 40.2% L 10 , 45% L 10 、48%L 10 , 50% L 10 , 53.4% L 10 , 58% L 10 , 60% L 10 .

[0114] For example:

[0115] L 10 When L is 4800mm, 12耳 It can be 1680mm to 2880mm, for example, 1680mm, 1800mm, 2000mm, 2340mm, 2553mm, 2680mm, 2780mm, 2802mm, 2880mm;

[0116] L 10 When L is 5000mm, 12耳 It can be 1750mm to 3000mm, for example, 1750mm, 1840mm, 1950mm, 2200mm, 2375mm, 2580mm, 2780mm, 2860mm, 3000mm;

[0117] L 10 When L is 6000mm, 12耳 It can be 2100mm to 3600mm, for example, 2100mm, 2300mm, 2500mm, 2860mm, 3000mm, 3180mm, 3368mm, 3560mm, 3600mm;

[0118] L 10 When L is 6200mm, 12耳 It can be 2170mm to 3720mm, for example, 2170mm, 2300mm, 2500mm, 2650mm, 2893mm, 3000mm, 3300mm, 3500mm, 3720mm.

[0119] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the length of the second pole ear 013 of this embodiment being too long and affecting the current collecting area of the second pole ear 013 of the other pole piece 001 matched therewith; on the other hand, it is possible to avoid the length of the second pole ear 013 of this embodiment being too short, thereby meeting the current collecting requirements of the pole piece 001 and helping to reduce the internal resistance of the battery cell.

[0120] See also Figure 1 or Figure 2 In one embodiment, along the first direction, the first electrode tab 012 and the second electrode tab 013 are at least partially disposed opposite to each other. Figure 1 Or the relative area of the tab 014 marked in 2.

[0121] The first tab 012 and the second tab 013 can be arranged completely opposite to each other, such as Figure 1 As shown; the first pole ear 012 and the second pole ear 013 are arranged relative to each other, as shown Figure 2 When the parts are arranged relative to each other, specifically, along the first direction, the ends of the first pole tab 012 and the second pole tab 013 that are close to each other are arranged relative to each other, the end of the first pole tab 012 away from the second pole tab 013 is staggered with the second pole tab 013, and the end of the second pole tab 013 away from the first pole tab 012 is staggered with the first pole tab 012.

[0122] exist Figure 2 In the electrode piece 001 shown, the first side 113 and the second side 114 of the other electrode piece 001 that matches the electrode piece 001 are both provided with tabs, and the electrode assembly formed by winding the electrode piece 001 is as shown in FIG. Figure 4 As shown, Figure 4 is a cross-sectional view of an electrode assembly provided in an embodiment of the present application. Figure 4 In the figure, the current collecting path of the second pole tab 013 is as follows: the second pole tab 013 first collects current toward the pole tab opposite area along the radial direction of the electrode assembly to form a second current collecting path I; through the pole tab opposite area, the second pole tab 013 collects current toward the first pole tab 012 along the axial direction of the electrode assembly to form a second current collecting path II.

[0123] It can be understood that when the first electrode tab 012 and the second electrode tab 013 are completely staggered along the first direction, after the second electrode tab 013 collects current, in addition to collecting current along the second current collecting path I and the second current collecting path II, it also needs to transfer current to the first electrode tab 012 along the winding direction of the electrode sheet 001. Therefore, it can be seen that by arranging the first electrode tab 012 and the second electrode tab 013 partially opposite each other along the first direction, after the second electrode tab 013 collects current, it can transfer current to the first electrode tab 012 only along the axial direction of the electrode assembly, thereby shortening the current collecting path of the second electrode tab 013 and further improving the current collecting capacity of the electrode sheet 001.

[0124] In addition, when only one of the positive and negative electrode sheets can have a tab 014 facing region due to the insulation spacing between the tabs 014, the tab 014 facing region can be optionally provided on the electrode sheet 001 where the first tab 012 is closer to the center hole of the electrode assembly. The specific reasons are as follows:

[0125] First, the electrode sheet 001, whose first tab 012 is closer to the center hole of the electrode assembly, is usually the positive electrode sheet. The positive tab is made of aluminum foil, while the negative tab is made of copper foil. Therefore, the resistivity of the positive tab is greater than that of the negative tab, and its current collecting capacity is weaker than that of the negative tab. Providing a corresponding area for the tab 014 on the positive tab can increase the total area of the positive tab, thereby improving the current collecting capacity of the positive tab.

[0126] Secondly, during fast charging, the positive electrode column needs to quickly transfer electricity to the electrode material of the positive electrode sheet. The arrangement of the tabs 014 on the positive electrode sheet allows the first tab 012 to transfer current to the second tab 013 along the width of the electrode sheet 001. This reduces the current transfer path, improves charging efficiency, and meets the fast charging requirements of the battery cell.

[0127] See also Figure 1 or Figure 2 In one embodiment, in the second direction, the second pole tab 013 has a second pole tab tail end 132 close to the pole piece tail end 112 , and the second pole tab tail end 132 and the pole piece tail end 112 are spaced apart.

[0128] In this way, after the electrode sheet 001 is wound into an electrode assembly, the outer periphery of the second electrode tab 013 and the outer periphery of the electrode assembly are arranged at radial intervals along the electrode assembly, so that the bent second electrode tab 013 can be located in the interval without exceeding the outer periphery of the electrode assembly, thereby improving the abutment between the electrode tab 014 and the battery cell shell when the electrode assembly is put into the shell, thereby improving the convenience of the electrode assembly being put into the shell.

[0129] In one embodiment, along the second direction, the distance between the second tab tail end 132 and the pole piece tail end 112 is L 12尾 , the length of the pole piece body 011 is L 10 , combined with the aforementioned L 12耳 Minimum value: 60% L 10 , Maximum value: 80% L 10 , and L 12头 Minimum value: 7% L 10 , Maximum value: 20% L 10 , we can know that: 0<L 12尾 ≤33% L 10 .

[0130] Understandable, L 12尾 Including but not limited to 1.7% L 10 , 4.6% L 10 , 9.1% L 10 、14% L 10 、19.6%L 10 , 22.6% L 10 , 28.7% L 10, 32% L 10 , 33% L 10 .

[0131] For example:

[0132] L 10 When L is 4800mm, 12尾 It can be 240mm to 1584mm, for example, 240mm, 400mm, 800mm, 900mm, 1053mm, 1200mm, 1480mm, 1500mm, 1584mm;

[0133] L 10 When L is 5000mm, 12尾 It can be 250mm to 1650mm, for example, 250mm, 400mm, 700mm, 900mm, 1150mm, 1300mm, 1580mm, 1600mm, 1650mm;

[0134] L 10 When L is 6000mm, 12尾 It can be 300mm to 1980mm, for example, 300mm, 600mm, 800mm, 1000mm, 1100mm, 1400mm, 1553mm, 1800mm, 1980mm;

[0135] L 10 When L is 6200mm, 12尾 It can be 310mm to 2046mm, for example, 310mm, 480mm, 800mm, 1000mm, 1553mm, 1680mm, 1980mm, 2000mm, 2046mm.

[0136] In this embodiment, through the above-mentioned arrangement, on the one hand, after the electrode sheet 001 is wound into an electrode assembly, the outer periphery of the second electrode tab 013 and the outer periphery of the electrode assembly are arranged at radial intervals along the electrode assembly, so that the bent electrode tab 014 can be located in the interval without exceeding the outer periphery of the electrode assembly; on the other hand, it can avoid the interval between the outer periphery of the second electrode tab 013 and the outer periphery of the electrode assembly being too large to affect the area of the second electrode tab 013, so that the current collecting capacity and internal resistance of the second electrode tab 013 can meet the requirements.

[0137] See also Figure 1 or Figure 2In one embodiment, in the second direction, the first tab 012 has a first tab head end 121 close to the tab head end 111 and a first tab tail end 122 close to the tab tail end 112. Along the second direction, the first tab tail end 122 and the tab tail end 112 are spaced apart, and / or, along the second direction, the first tab head end 121 and the tab head end 111 are spaced apart.

[0138] Specifically, along the second direction, the first pole tab tail end 122 and the pole piece tail end 112 are spaced apart, or, along the second direction, the first pole tab head end 121 and the pole piece head end 111 are spaced apart, or, along the second direction, the first pole tab tail end 122 and the pole piece tail end 112 are spaced apart, and the first pole tab head end 121 and the pole piece head end 111 are spaced apart.

[0139] Among them, when the first pole ear tail end 122 and the pole piece tail end 112 are arranged at intervals, after the pole piece 001 is wound into an electrode assembly, the outer periphery of the first pole ear 012 and the outer periphery of the electrode assembly are arranged at intervals along the radial direction of the electrode assembly, thereby facilitating the arrangement of the first pole ear 012 of another pole piece 001.

[0140] Furthermore, when the first tab tip 121 and the electrode sheet tip 111 are spaced apart, a groove can be formed on the end surface of the electrode assembly formed by rolling the electrode sheet 001, near the center hole, based on the spacing, so that the bent first tab 012 can be poured into the groove. This not only reduces the stacking height of the bent first tabs 012, but also improves the flatness of the stacked first tabs 012, thereby improving the ease of welding the first tabs 012 to the current collecting plate.

[0141] Moreover, when the first pole tab end 121 and the pole piece end 111 are spaced apart, the first pole tab 012 near the pole piece end 111 can be prevented from blocking the center hole of the electrode assembly after bending, thereby improving the smoothness of the electrolyte flowing into the center hole and further ensuring the wetting efficiency of the electrode assembly.

[0142] See also Figure 1 or Figure 2 In one embodiment, along the second direction, the distance between the first tab tail end 122 and the pole piece tail end 112 is L 11尾 The length of the pole piece body 011 is L 10 , satisfying: L 11尾 =60%L 10 ~78% L 10 .

[0143] It can be understood that the electrode assembly includes two pole pieces 001 of opposite polarity, serving as the positive and negative pole pieces, respectively. The first pole tab 012 of this embodiment is positioned adjacent to the pole piece head end 111, while the first pole tab 012 of the other pole piece 001, which is wound together with the pole piece 001 of this embodiment to form the electrode assembly, is positioned away from the pole piece head end 111. Therefore, to prevent interference between the first pole tab 012 of the pole piece 001 of this embodiment and the pole tab 014 of the other pole piece 001, the spacing between the first pole tab tail end 122 and the pole piece tail end 112 needs to be larger to facilitate the placement of the pole tab 014 of the other pole piece 001.

[0144] Among them, L 11尾 Including but not limited to 60% L 10 , 63% L 10 , 65.2% L 10 , 68% L 10 、69%L 10 , 70% L 10 , 73.4% L 10 , 76% L 10 , 78% L 10 .

[0145] For example:

[0146] L 10 When L is 4800mm, 11尾 It can be 2880mm to 3744mm, for example, 2880mm, 2940mm, 3080mm, 3200mm, 3453mm, 3520mm, 3680mm, 3700mm, 3744mm;

[0147] L 10 When L is 5000mm, 11尾 It can be 3000mm to 3900mm, for example, 3000mm, 3300mm, 3400mm, 3500mm, 3650mm, 3700mm, 3808mm, 3880mm, 3900mm;

[0148] L 10 When L is 6000mm, 11尾 It can be 3600mm to 4680mm, for example, 3600mm, 3700mm, 3800mm, 4100mm, 4253mm, 4400mm, 4580mm, 4600mm, 4680mm;

[0149] L 10 When L is 6200mm, 11尾It can be 3720mm to 4836mm, for example, 3720mm, 380mm, 4000mm, 4100mm, 4353mm, 4580mm, 4780mm, 4800mm, 4836mm.

[0150] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the spacing between the first pole tab tail end 122 and the pole piece tail end 112 being too large, so that the area of the first pole tab 012 of this embodiment can meet the current collection requirements and have a suitable internal resistance; on the other hand, it is possible to avoid the spacing between the first pole tab tail end 122 and the pole piece tail end 112 being too small, which affects the arrangement of the first pole tab 012 of the other pole piece 001.

[0151] In one embodiment, along the second direction, the distance between the first tab end 121 and the pole piece end 111 is L 11头 The length of the pole piece body 011 is L 10 , satisfying: L 11头 =7% L 10 ~20% L 10 .

[0152] Among them, L 11头 Including but not limited to 7% L 10 , 8.6% L 10 , 9.1% L 10 , 10% L 10 、13.6%L 10 、15.6% L 10 、18.7% L 10 , 19% L 10 , 20% L 10 .

[0153] For example:

[0154] L 10 When L is 4800mm, 11头 It can be 336mm to 960mm, for example, 336mm, 400mm, 500mm, 600mm, 753mm, 800mm, 880mm, 900mm, 960mm;

[0155] L 10 When L is 5000mm, 11头 It can be 350mm to 1000mm, for example, 350mm, 400mm, 500mm, 600mm, 753mm, 800mm, 880mm, 960mm, 1000mm;

[0156] L 10 When L is 6000mm, 11头It can be 420mm to 1200mm, for example, 420mm, 463mm, 500mm, 600mm, 753mm, 800mm, 880mm, 960mm, 1200mm;

[0157] L 10 When L is 6200mm, 11头 It can be 434mm to 1240mm, for example, 434mm, 480mm, 500mm, 600mm, 753mm, 880mm, 980mm, 1060mm, and 1240mm.

[0158] In this embodiment, through the above definition, on the one hand, the spacing L can be avoided 11头 If the size is too small, the first tab 012 will be stacked too high at the center of the electrode assembly after being bent, thereby controlling the stacking height of the tab 014 after being bent and improving the flatness of the tab 014 stacking; on the other hand, the spacing L can be avoided. 11头 Too large affects the length of the first electrode tab 012 , thereby ensuring the current collecting area of the first electrode tab 012 and further ensuring the current collecting capacity of the electrode piece 001 .

[0159] In one embodiment, along the second direction, the length of the first tab 012 is L 11耳 The length of the pole piece body 011 is L 10 , satisfying: L 11耳 =15% L 10 ~20% L 10 .

[0160] Among them, L 11耳 Including but not limited to 15% L 10 、16% L 10 、16.2% L 10 、17% L 10 、18%L 10 、18.2% L 10 、19.4% L 10 、19.5% L 10 , 20% L 10 .

[0161] For example:

[0162] L 10 When L is 4800mm, 11耳 It can be 720mm to 960mm, for example, 720mm, 760mm, 812mm, 8340mm, 8553mm, 8680mm, 908mm, 950mm, 960mm;

[0163] L 10When L is 5000mm, 11耳 It can be 750mm to 1000mm, for example, 750mm, 800mm, 850mm, 900mm, 905mm, 968mm, 980mm, 990mm, 1000mm;

[0164] L 10 When L is 6000mm, 11耳 It can be 900mm to 1200mm, for example, 900mm, 930mm, 990mm, 1000mm, 1050mm, 1080mm, 1100mm, 1160mm, 1200mm;

[0165] L 10 When L is 6200mm, 11耳 It can be 930mm to 1240mm, for example, 930mm, 1000mm, 1010mm, 1050mm, 1100mm, 1180mm, 1200mm, 1210mm, and 1240mm.

[0166] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the length of the first pole ear 012 of this embodiment being too long and affecting the current collecting area of the first pole ear 012 of the other pole piece 001 matched therewith; on the other hand, it is possible to avoid the length of the first pole ear 012 of this embodiment being too short, thereby meeting the current collecting requirements of the pole piece 001 and reducing the internal resistance of the battery cell.

[0167] See also Figure 3 In one embodiment, in the second direction, the pole piece body 011 has a pole piece head end 111 and a pole piece tail end 112 ; in the second direction, the second pole ear 013 is arranged closer to the pole piece head end 111 than the first pole ear 012 .

[0168] It can be understood that the pole piece head end 111 is the end of the pole piece 001 close to the center of the electrode assembly after the pole piece 001 is wound into the electrode assembly, and the pole piece tail end 112 is the end located at the periphery of the electrode assembly.

[0169] Typically, the first electrode tab 012 of the negative electrode is located at a position on the first side 113 away from the electrode tip 111, and the second electrode tab 013 is located at a position on the second side 114 close to the electrode tip 111. Therefore, in this embodiment, the electrode 001 in which "the second electrode tab 013 is located closer to the electrode tip 111 than the first electrode tab 012" is typically a electrode 001 with negative polarity.

[0170] Furthermore, the first pole tab 012 is arranged at a position on the first side 113 away from the pole piece head end 111, and the second pole tab 013 is arranged at a position on the second side 114 close to the pole piece head end 111. Along the width direction of the pole piece body 011, the end of the first pole tab 012 away from the pole piece head end 111 and the end of the second pole tab 013 close to the pole piece head end 111 can be arranged relative to each other, or the first pole tab 012 and the second pole tab 013 can be completely staggered.

[0171] In this embodiment, through the above-mentioned setting, the first pole ear 012 can mainly collect current in the area close to the tail end 112 of the pole piece, and the second pole ear 013 can mainly collect current in the area close to the head end 111 of the pole piece, so that the first pole ear 012 and the second pole ear 013 can take into account the current collection in the length direction of the entire pole piece 001, thereby shortening the current collection path of the pole piece 001 and reducing the internal resistance of the battery cell.

[0172] See also Figure 3 In one embodiment, in the second direction, the second electrode tab 013 has a second electrode tab head end 131 close to the electrode head end 111 , and the second electrode tab head end 131 and the electrode head end 111 are spaced apart.

[0173] It's understandable that after the electrode sheet 001 is wound into an electrode assembly, the tab 014 is parallel to the electrode assembly's axis, occupying a relatively large height, which negatively impacts the cell's energy density. For this reason, the tab 014 near the center of the electrode assembly is typically bent toward the center to reduce the space occupied by the tab 014. Directly bending the tab 014, however, not only results in a higher stack height after bending, but also poorly flattened stacking, hindering welding of the tab 014 to the current collector.

[0174] Based on this, in this embodiment, by spacing the second electrode tab tip 131 and the electrode sheet tip 111, a groove is formed on the end surface of the electrode assembly formed by rolling the electrode sheet 001, near the center hole, so that the bent second electrode tab 013 can be poured into the groove. This not only reduces the stacking height of the bent second electrode tabs 013, but also improves the flatness of the stacked second electrode tabs 013, thereby improving the ease of welding the second electrode tabs 013 to the current collecting plate.

[0175] In addition, the above arrangement can also prevent the second electrode tab 013 near the electrode head end 111 from blocking the central hole of the electrode assembly after bending, thereby improving the smoothness of the electrolyte flowing into the central hole and further ensuring the wetting efficiency of the electrode assembly.

[0176] See also Figure 3 In one embodiment, along the second direction, the distance between the second tab end 131 and the pole piece end 111 is L 22头, the length of the pole piece body 011 is L 20 , satisfying: L 22头 =7% L 20 ~20%L 20 .

[0177] Understandable, L 22头 Including but not limited to 7% L 20 , 8.6% L 20 , 9.1% L 20 , 10% L 20 、13.6%L 20 、15.6% L 20 、18.7% L 20 、19% L 20 , 20% L 20 .

[0178] For example:

[0179] L 20 When L is 5000mm, 22头 It can be 350mm to 1000mm, for example, 350mm, 400mm, 500mm, 600mm, 753mm, 800mm, 880mm, 960mm, 1000mm;

[0180] L 20 When L is 5200mm, 22头 It can be 364mm to 1040mm, for example, 364mm, 400mm, 500mm, 600mm, 753mm, 800mm, 880mm, 960mm, 1040mm;

[0181] L 20 When L is 6200mm, 22头 It can be 434mm to 1240mm, for example, 434mm, 480mm, 500mm, 600mm, 753mm, 880mm, 980mm, 1060mm, 1240mm;

[0182] L 20 When L is 6400mm, 22头 It can be 448mm to 1280mm, for example, 448mm, 480mm, 500mm, 600mm, 753mm, 880mm, 980mm, 1060mm, and 1280mm.

[0183] In this embodiment, through the above definition, on the one hand, the spacing L can be avoided 22头Too small will cause the second tab 013 to be stacked too high at the center of the electrode assembly after bending, thereby controlling the stacking height of the tab 014 after bending and improving the flatness of the tab 014 stacking; on the other hand, it can avoid the spacing L 22头 Too large affects the length of the second electrode tab 013 , thereby ensuring the current collecting area of the second electrode tab 013 and further ensuring the current collecting capacity of the electrode piece 001 .

[0184] See also Figure 3 In one embodiment, along the second direction, the second pole tab 013 has a second pole tab tail end 132 close to the pole piece tail end 112 , and the second pole tab tail end 132 and the pole piece tail end 112 are spaced apart.

[0185] In this embodiment, by spacing the second pole tab tail end 132 and the pole piece tail end 112, after the pole piece 001 is wound into an electrode assembly, the outer periphery of the second pole tab 013 and the outer periphery of the electrode assembly can be spaced apart along the radial direction of the electrode assembly, so that the bent second pole tab 013 can be located in the spacing without exceeding the outer periphery of the electrode assembly, thereby improving the contact between the pole tab 014 and the battery cell shell when the electrode assembly is put into the shell, thereby improving the convenience of the electrode assembly being put into the shell.

[0186] See also Figure 3 In one embodiment, along the second direction, there is a distance L between the second tab tail end 132 and the pole piece tail end 112. 22尾 The length of the pole piece body 011 is L 20 , satisfying: L 22尾 =60L 20 ~78%L 20 .

[0187] It can be understood that the electrode assembly includes two pole pieces 001 of opposite polarity, serving as the positive and negative pole pieces, respectively. The second pole tab 013 of this embodiment is positioned adjacent to the pole piece head end 111, while the second pole tab 013 of the other pole piece 001 wound together with the pole piece 001 of this embodiment to form the electrode assembly is positioned away from the pole piece head end 111. Therefore, to prevent the second pole tab 013 of the pole piece 001 of this embodiment from interfering with the pole tab 014 of the other pole piece 001, the spacing between the second pole tab tail end 132 and the pole piece tail end 112 needs to be larger to facilitate the placement of the pole tab 014 of the other pole piece 001.

[0188] Among them, L 22尾 Including but not limited to 60% L 20 , 63% L 20 , 65.2% L 20 , 68% L 20 、69%L 20 , 70% L 20 , 73.4% L20 , 76% L 20 , 78% L 20 .

[0189] For example:

[0190] L 20 When L is 5000mm, 22尾 It can be 3000mm to 3900mm, for example, 3000mm, 3300mm, 3400mm, 3500mm, 3650mm, 3700mm, 3808mm, 3880mm, 3900mm;

[0191] L 20 When L is 5200mm, 22尾 It can be 3120mm~4056mm, for example, 3000mm, 3300mm, 3400mm, 3500mm, 3650mm, 3700mm, 3808mm, 3880mm, 4056mm;

[0192] L 20 When L is 6200mm, 22尾 It can be 3720mm to 4836mm, for example, 3720mm, 380mm, 4000mm, 4200mm, 4353mm, 4580mm, 4780mm, 4800mm, 4836mm;

[0193] L 20 When L is 6400mm, 22尾 It can be 3840mm to 4992mm, for example, 3720mm, 380mm, 4000mm, 4200mm, 4353mm, 4580mm, 4780mm, 4800mm, 4992mm.

[0194] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the spacing between the second pole tab tail end 132 and the pole piece tail end 112 being too large, so that the area of the second pole tab 013 of this embodiment can meet the current collection requirements and reduce the internal resistance; on the other hand, it is possible to avoid the spacing between the second pole tab tail end 132 and the pole piece tail end 112 being too small, which affects the arrangement of the second pole tab 013 of the other pole piece 001.

[0195] See also Figure 3 In one embodiment, along the second direction, the length of the second tab 013 is L 22耳 , the length of the pole piece body 011 is L 20 , satisfying: L 22耳 =15% L 20 ~20% L 20 .

[0196] Among them, L 22耳 Including but not limited to 15% L 20 、16% L 20 、16.2% L 20 、17% L 20 、18%L 20 、18.2% L 20 、19.4% L 20 、19.5% L 20 , 20% L 20 .

[0197] For example:

[0198] L 20 When L is 5000mm, 22耳 It can be 750mm to 1000mm, for example, 750mm, 800mm, 850mm, 900mm, 905mm, 968mm, 980mm, 990mm, 1000mm;

[0199] L 20 When L is 5200mm, 22耳 It can be 780mm to 1040mm, for example, 780mm, 800mm, 850mm, 900mm, 905mm, 968mm, 980mm, 990mm, 1040mm;

[0200] L 20 When L is 6200mm, 22耳 It can be 930mm to 1240mm, for example, 930mm, 1000mm, 1020mm, 1050mm, 1100mm, 1180mm, 1200mm, 1220mm, 1240mm;

[0201] L 20 When L is 6400mm, 22耳 It can be 960mm to 1280mm, for example, 960mm, 1000mm, 1020mm, 1050mm, 1100mm, 1180mm, 1200mm, 1220mm, and 1280mm.

[0202] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the length of the second pole ear 013 of this embodiment being too long and affecting the current collecting area of the second pole ear 013 of the other pole piece 001 matched therewith; on the other hand, it is possible to avoid the length of the second pole ear 013 of this embodiment being too short, thereby meeting the current collecting requirements of the pole piece 001 and reducing the internal resistance of the battery cell.

[0203] See also Figure 3 In one embodiment, in the second direction, the first pole tab 012 has a first pole tab head end 121 close to the pole piece head end 111 and a first pole tab tail end 122 close to the pole piece tail end 112; along the second direction, the first pole tab tail end 122 and the pole piece tail end 112 are spaced apart, and / or, along the second direction, the first pole tab head end 121 and the pole piece head end 111 are spaced apart.

[0204] Specifically, along the second direction, the first pole tab tail end 122 and the pole piece tail end 112 are spaced apart, or, along the second direction, the first pole tab head end 121 and the pole piece head end 111 are spaced apart, or, along the second direction, the first pole tab tail end 122 and the pole piece tail end 112 are spaced apart, and the first pole tab head end 121 and the pole piece head end 111 are spaced apart.

[0205] When the first tab tail end 122 and the electrode sheet tail end 112 are spaced apart, after the electrode sheet 001 is wound into an electrode assembly, the outer periphery of the first tab 012 and the outer periphery of the electrode assembly are spaced apart along the radial direction of the electrode assembly. This allows the bent first tab 012 to be located within this space without exceeding the outer periphery of the electrode assembly. This improves the contact between the tab 014 and the cell housing when the electrode assembly is inserted into the battery case, thereby enhancing the ease of inserting the electrode assembly into the battery case. Furthermore, the stacking height of the bent first tabs 012 can be reduced, and the flatness of the stacked first tabs 012 can be improved, thereby enhancing the ease of welding the first tabs 012 to the current collector.

[0206] In addition, when the first pole tab head end 121 and the pole piece head end 111 are spaced apart, after the pole piece 001 is wound into an electrode assembly, the outer periphery of the first pole tab 012 and the outer periphery of the electrode assembly are spaced apart along the radial direction of the electrode assembly, thereby facilitating the arrangement of the first pole tab 012 of another pole piece 001.

[0207] See also Figure 3 In one embodiment, along the second direction, the distance between the first tab end 121 and the pole piece end 111 is L 21头 The length of the pole piece body 011 is L 20 , meet: 40% L 20 ≤L 21头 ≤50%L 20 .

[0208] Among them, L 21头 Including but not limited to 40% L 20 , 43% L 20 , 44.2% L 20 , 45% L 20 46.1% L 20 , 47.2% L 20 48.6% L20 49.9% L 20 , 50% L 20 .

[0209] For example:

[0210] L 20 When L is 5000mm, 21头 It can be 2000mm~2500mm, for example, 2000mm, 2040mm, 2100mm, 2160mm, 2230mm, 2300mm, 2416mm, 2489mm, 2500mm;

[0211] L 20 When L is 5200mm, 21头 It can be 2080mm to 2600mm, for example, 2080mm, 100mm, 2160mm, 2230mm, 2300mm, 2416mm, 2489mm, 2538mm, 2600mm;

[0212] L 20 When L is 6200mm, 21头 It can be 2480mm to 3100mm, for example, 2480mm, 2489mm, 2538mm, 2600mm, 2775mm, 2880mm, 2988mm, 2096mm, 3100mm;

[0213] L 20 When L is 6400mm, 21头 It can be 2560mm to 3200mm, for example, 2560mm, 2600mm, 2775mm, 2880mm, 2988mm, 2096mm, 3100mm, 3160mm, and 3200mm.

[0214] It is understood that the electrode assembly includes two electrode pieces 001 with opposite polarities. When the electrode piece 001 of this embodiment is wound together with another electrode piece 001 to form an electrode assembly, in order to ensure that the first electrode tab 012 of the other electrode piece 001 has sufficient current collecting area, it is necessary to control the distance between the first electrode tab head end 121 and the electrode piece head end 111 of this embodiment to avoid the distance being too small and affecting the arrangement of the first electrode tab 012 of the other electrode piece 001.

[0215] Based on this, in this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the spacing between the first pole tab head end 121 and the pole piece head end 111 being too large, which would cause the length of the first pole tab 012 to be too small, so that the length of the first pole tab 012 can meet the current collecting requirements of the pole piece 001 and reduce the internal resistance of the battery cell; on the other hand, it is possible to avoid the spacing between the first pole tab head end 121 and the pole piece head end 111 being too small, which would affect the current collecting area of the first pole tab 012 of the other pole piece 001 that cooperates with it.

[0216] See also Figure 3 In one embodiment, along the second direction, the distance between the first tab tail end 122 and the pole piece tail end 112 is L 21尾 The length of the pole piece body 011 is L 20 , satisfying: 0<L 21尾 ≤30% L 20 .

[0217] Understandable, L 21尾 Including but not limited to 1.7% L 20 , 4.6% L 20 , 9.1% L 20 , 14% L 20 、19.6%L 20 , 22.6% L 20 , 28.7% L 20 , 29% L 20 、30% L 20 .

[0218] For example:

[0219] L 20 When L is 5000mm, 21尾 It can be 250mm to 1500mm, for example, 250mm, 400mm, 800mm, 900mm, 1053mm, 1200mm, 1483mm, 1490mm, 1500mm;

[0220] L 20 When L is 5200mm, 21尾 It can be 260mm to 1560mm, for example, 260mm, 400mm, 700mm, 900mm, 1150mm, 1300mm, 1458mm, 1460mm, 1560mm;

[0221] L 20 When L is 6200mm, 21尾It can be 310mm to 1860mm, for example, 310mm, 600mm, 800mm, 1100mm, 1553mm, 1680mm, 1798mm, 1800mm, 1860mm;

[0222] L 20 When L is 6400mm, 21尾 It can be 320mm to 1920mm, for example, 320mm, 480mm, 800mm, 1000mm, 1553mm, 1680mm, 1780mm, 1800mm, and 1920mm.

[0223] In this embodiment, through the above-mentioned arrangement, on the one hand, after the electrode sheet 001 is wound into an electrode assembly, the periphery of the first electrode tab 012 and the periphery of the electrode assembly can be arranged at radial intervals along the electrode assembly, so that the bent electrode tab 014 can be located in the interval without exceeding the periphery of the electrode assembly; on the other hand, it can avoid the interval between the periphery of the first electrode tab 012 and the electrode assembly being too large, which affects the area of the first electrode tab 012, so that the current collecting capacity and internal resistance of the first electrode tab 012 can meet the requirements.

[0224] See also Figure 3 In one embodiment, along the second direction, the length of the first tab 012 is L 21耳 , the length of the pole piece body 011 is L 20 , meet: 30% L 20 ≤L 21耳 ≤50% L 20 .

[0225] Among them, L 21耳 Including but not limited to 30% L 20 , 33% L 20 、35.2% L 20 、38% L 20 、40%L 20 42% L 20 , 46.4% L 20 , 49% L 20 , 50% L 20 .

[0226] For example:

[0227] L 20 When L is 5000mm, 21耳 It can be 1500mm to 2500mm, for example, 1500mm, 1700mm, 1812mm, 1940mm, 2053mm, 2280mm, 2380mm, 2402mm, 3500mm;

[0228] L 20 When L is 5200mm, 21耳 It can be 1560mm to 2600mm, for example, 1560mm, 1640mm, 1800mm, 1900mm, 2053mm, 2200mm, 2380mm, 2460mm, 2600mm;

[0229] L 20 When L is 6200mm, 21耳 It can be 1860mm to 3100mm, for example, 1860mm, 1900mm, 2000mm, 2260mm, 2400mm, 2680mm, 2868mm, 3060mm, 3100mm;

[0230] L 20 When L is 6400mm, 21耳 It can be 1920mm to 3200mm, for example, 1920mm, 2000mm, 2200mm, 2350mm, 2653mm, 2780mm, 2880mm, 3000mm, 3200mm.

[0231] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the length of the first pole ear 012 of this embodiment being too long and affecting the current collecting area of the first pole ear 012 of the other pole piece 001 matched therewith; on the other hand, it is possible to avoid the length of the first pole ear 012 of this embodiment being too short, thereby meeting the current collecting requirements of the pole piece 001 and reducing the internal resistance of the battery cell.

[0232] See also Figure 3 In one embodiment, along the second direction, the first electrode tab 012 and the second electrode tab 013 are spaced apart from each other.

[0233] It can be understood that along the first direction, the first electrode tab 012 and the second electrode tab 013 are completely staggered.

[0234] In this embodiment, through the above-mentioned arrangement, when the electrode sheet 001 of this embodiment is a negative electrode sheet, the electrode tab 014 of the positive electrode sheet matched with the electrode sheet 001 can have a larger length, thereby increasing the electrode tab area of the positive electrode sheet, and can make the first electrode tab 012 and the second electrode tab 013 of the positive electrode sheet have positions arranged relative to each other along the first direction, so that the current collecting path of the positive electrode sheet is shorter, thereby improving the current collecting capacity of the positive electrode sheet.

[0235] See also Figure 5 , Figure 5This is a schematic diagram of the coated and uncoated areas provided in an embodiment of the present application. In one embodiment, a pole piece 001 includes a coated area coated with an active material and an uncoated area uncoated with the active material. The pole piece body 011 is located in the coated area, and the pole tab 014 is located in the uncoated area.

[0236] Specifically, the electrode 001 includes a current collector with a coated area and a non-coated area. Along the width of the electrode body 011, the non-coated area is located adjacent to the long side of the electrode body 011. The current collector in the non-coated area forms the electrode tab 014. The current collector in the coated area is used to coat the active material.

[0237] In this embodiment, the tab 014 and the current collector of the electrode piece 001 are integrally formed, which can reduce the internal resistance of the electrode piece 001 and improve the stability of the connection between the tab 014 and the current collector.

[0238] See also Figure 5 In one embodiment, the tab 014 is a die-cut tab 014. Die-cutting the tab 014 means using a mold and a cutting tool, such as a laser cutter, to cut the tab 014 into a desired shape in the non-coating area of the current collector.

[0239] In this embodiment, by adopting die-cutting the tabs 014 , the forming method of the tabs 014 can be made simple and convenient, and the consistency of the tabs 014 can be improved, ensuring that the shape, size and spacing of the tabs 014 meet the design requirements.

[0240] See also Figure 6 , Figure 6 FIG. 1 is a schematic diagram of the structure of the tab 014 provided in an embodiment of the present application. In one embodiment, the die-cut width of the tab 014 is W, which satisfies 2 mm ≤ W ≤ 6 mm.

[0241] Illustratively, W includes but is not limited to 2mm, 2.2mm, 2.5mm, 2.6mm, 3mm, 3.2mm, 3.62mm, 4.15mm, 4.8mm, 5mm, 5.33mm, 5.42mm, 5.62mm, 5.82mm, 5.96mm, 5.99mm, and 6mm.

[0242] Specifically, if the distance from the pole piece body 011 to the pole piece head end 111 is within 35% of the length of the pole piece body 011, the die-cut width W of the pole tab 014 is 2 to 4 mm. If the distance from the pole piece body 011 to the pole piece head end 111 is greater than 35% of the length of the pole piece body 011, the die-cut width W of the pole tab 014 is 4 to 6 mm. Furthermore, the die-cut width W of the pole tab 014 gradually increases as it moves away from the pole piece head end 111. This reduces the obstruction of the tab 014 from being flattened at the connection between the tab 014 and the coating area, thereby improving the ease of flattening the tab 014 and thereby improving the flattening efficiency.

[0243] In this embodiment, through the above-mentioned limitation, on the one hand, it is possible to avoid the die-cutting width of the tab 014 being too small and easy to break, thereby ensuring the reliability of the connection between the tab 014 and the coating area; on the other hand, it is possible to avoid the die-cutting width of the tab 014 being too large, resulting in a large resistance to flattening the tab 014.

[0244] See also Figure 6 In one embodiment, the die-cutting angle of the tab 014 is α, which satisfies 55°≤α≤85°.

[0245] It can be understood that the die-cutting angle is the acute angle between the laser cutting track and the length direction of the pole piece 001.

[0246] Exemplarily, α includes but is not limited to 55°, 57.5°, 59°, 60°, 62.5°, 66°, 68°, 70°, 71.3°, 75°, 76.4°, 80°, 81°, 83.3°, 84°, and 85°.

[0247] In this embodiment, through the above definition, when the tabs 014 are flattened, the bending of the tabs 014 can be guided, so that adjacent tabs 014 are partially overlapped, thereby reducing the interference between adjacent tabs 014 and improving the stacking flatness of the tabs 014 after flattening.

[0248] In one embodiment, the die-cutting height of the tab 014 is H, which satisfies: 5 mm ≤ H ≤ 7.5 mm.

[0249] Illustratively, H includes but is not limited to 5 mm, 5.2 mm, 5.48 mm, 5.9 mm, 6 mm, 6.5 mm, 6.7 mm, 6.9 mm, 7 mm, 7.15 mm, 7.3 mm, 7.46 mm, and 7.5 mm.

[0250] In this embodiment, the above-mentioned limitation can, on the one hand, prevent the tab 014 from being cut too small, which is not conducive to forming a sufficient welding surface for welding with the collecting plate after the tab 014 is bent; on the other hand, it can prevent the tab 014 from being cut too large, which takes up more space inside the battery cell.

[0251] See also Figure 7 , Figure 7 002 is a schematic diagram of the structure of the electrode assembly 002 provided in an embodiment of the present application. Accordingly, an embodiment of the present application provides an electrode assembly 002, and the electrode assembly 002 includes the aforementioned electrode piece 001.

[0252] It can be understood that the electrode assembly 002 includes a positive electrode sheet, a separator, and a negative electrode sheet stacked or wound in sequence. The positive electrode sheet is one of the aforementioned electrode sheets 001, or the negative electrode sheet is one of the aforementioned electrode sheets 001, or the positive electrode sheet is a portion of the aforementioned electrode sheet 001, and the negative electrode sheet is another portion of the aforementioned electrode sheet 001.

[0253] Specifically, the first structure of the positive electrode sheet may be: the positive electrode sheet includes a electrode body 011 and a electrode tab 014. In the first direction, the electrode body 011 has a first side 113 and a second side 114 that are arranged opposite to each other. The electrode tab 014 includes a first electrode tab 012 and a second electrode tab 013. The first electrode tab 012 is arranged on the first side 113, and the second electrode tab 013 is arranged on the second side 114. In the second direction, the electrode body 011 has a electrode head end 111 and a electrode tail end 112. In the second direction, the second electrode tab 013 is arranged farther away from the electrode head end 111 than the first electrode tab 012. In the second direction, the second electrode tab 013 has a second electrode tab head end 131 close to the electrode head end 111. The second electrode tab head end 131 and the electrode head end 111 are spaced apart. Along the second direction, the spacing between the second electrode tab head end 131 and the electrode head end 111 is L 12头 , the length of the pole piece body 011 is L 10 , meet: 7% L 10 ≤L 12头 ≤20% L 10 Along the second direction, the length of the second tab 013 is L 12耳 , meet: 60% L 10 ≤L 12耳 ≤80% L 10 Along the first direction, the first pole tab 012 and the second pole tab 013 are arranged opposite to each other. In the second direction, the second pole tab 013 has a second pole tab tail end 132 close to the pole piece tail end 112, and the second pole tab tail end 132 and the pole piece tail end 112 are spaced apart. Along the second direction, the distance between the second pole tab tail end 132 and the pole piece tail end 112 is L 12尾 , satisfying: 0<L 12尾 ≤35% L 10 In the second direction, the first tab 012 has a first tab head end 121 close to the tab head end 111 and a first tab tail end 122 close to the tab tail end 112. Along the second direction, the first tab tail end 122 and the tab tail end 112 are spaced apart, and / or, along the second direction, the first tab head end 121 and the tab head end 111 are spaced apart. Along the second direction, the spacing between the first tab tail end 122 and the tab tail end 112 is L 11尾 , the length of the pole piece body 011 is L 10 , satisfying: L 11尾 =60% L 10 ~78% L10 Along the second direction, the distance between the first tab end 121 and the pole piece end 111 is L 11头 , the length of the pole piece body 011 is L 10 , satisfying: L 11头 =7% L 10 ~20% L 10 Along the second direction, the length of the first tab 012 is L 11耳 , the length of the pole piece body 011 is L 10 , satisfying: L 11耳 =15% L 10 ~20% L 10 .

[0254] The second structure of the positive electrode sheet may be: the positive electrode sheet includes a electrode body 011 and a electrode tab 014. In the first direction, the electrode body 011 has a first side 113 and a second side 114 that are arranged opposite to each other. The electrode tab 014 includes a first electrode tab 012 and a second electrode tab 013. The first electrode tab 012 is arranged on the first side 113, and the second electrode tab 013 is arranged on the second side 114. In the second direction, the electrode body 011 has a electrode head end 111 and a electrode tail end 112. In the second direction, the second electrode tab 013 is arranged farther away from the electrode head end 111 than the first electrode tab 012. In the second direction, the second electrode tab 013 has a second electrode tab head end 131 close to the electrode head end 111. The second electrode tab head end 131 and the electrode head end 111 are spaced apart. Along the second direction, the spacing between the second electrode tab head end 131 and the electrode head end 111 is L 12头 , the length of the pole piece body 011 is L 10 , meet: 30% L 10 ≤L 12头 ≤40%L 10 Along the second direction, the length of the second tab 013 is L 12耳 , satisfying: L 12耳 =35% L 10 ~60% L 10 Along the first direction, the first pole tab 012 and the second pole tab 013 are partially arranged opposite to each other. In the second direction, the second pole tab 013 has a second pole tab tail end 132 close to the pole piece tail end 112, and the second pole tab tail end 132 and the pole piece tail end 112 are spaced apart. Along the second direction, the distance between the second pole tab tail end 132 and the pole piece tail end 112 is L 12尾 , satisfying: 0<L 12尾 ≤35% L 10In the second direction, the first tab 012 has a first tab head end 121 close to the tab head end 111 and a first tab tail end 122 close to the tab tail end 112. Along the second direction, the first tab tail end 122 and the tab tail end 112 are spaced apart, and / or, along the second direction, the first tab head end 121 and the tab head end 111 are spaced apart. Along the second direction, the spacing between the first tab tail end 122 and the tab tail end 112 is L 11尾 The length of the pole piece body 011 is L 10 , satisfying: L 11尾 =60% L 10 ~78% L 10 Along the second direction, the distance between the first tab end 121 and the pole piece end 111 is L 11头 The length of the pole piece body 011 is L 10 , satisfying: L 11头 =7% L 10 ~20% L 10 Along the second direction, the length of the first tab 012 is L 11耳 The length of the pole piece body 011 is L 10 , satisfying: L 11耳 =15% L 10 ~20% L 10 .

[0255] Regarding the first and second structures of the above-mentioned positive electrode sheet, the negative electrode sheet can be a conventional structure, and the negative electrode sheet can also include a electrode body 011 and a pole lug 014. In the first direction, the electrode body 011 has a first side 113 and a second side 114 arranged opposite to each other. The pole lug 014 includes a first pole lug 012 and a second pole lug 013. The first pole lug 012 is arranged on the first side 113, and the second pole lug 013 is arranged on the second side 114. In the second direction, the electrode body 011 has a pole piece head end 111 and a pole piece tail end 112. In the second direction, the second pole lug 013 is arranged closer to the pole piece head end 111 than the first pole lug 012. In the second direction, the second pole lug 013 has a second pole lug head end 131 close to the pole piece head end 111, and the second pole lug head end 131 and the pole piece head end 111 are arranged at intervals. Along the second direction, the spacing between the second pole lug head end 131 and the pole piece head end 111 is L 22头 The length of the pole piece body 011 is L 20 , satisfying: L 22头 =7% L 20 ~20% L 20 Along the second direction, the second pole tab 013 has a second pole tab tail end 132 close to the pole piece tail end 112, and the second pole tab tail end 132 and the pole piece tail end 112 are spaced apart. Along the second direction, the length dimension of the second pole tab 013 is L22耳 , the length of the pole piece body 011 is L 20 , satisfying: L 22耳 =15% L 20 ~20%L 20 In the second direction, the first tab 012 has a first tab head end 121 close to the tab head end 111 and a first tab tail end 122 close to the tab tail end 112; along the second direction, the first tab tail end 122 and the tab tail end 112 are spaced apart, and / or, along the second direction, the first tab head end 121 and the tab head end 111 are spaced apart. Along the second direction, the spacing between the first tab head end 121 and the tab head end 111 is L 21头 , the length of the pole piece body 011 is L 20 , meet: 40% L 20 ≤L 21头 ≤50%L 20 Along the second direction, the distance between the first tab tail end 122 and the pole piece tail end 112 is L 21尾 , the length of the pole piece body 011 is L 20 , satisfying: 0<L 21尾 ≤30% L 20 Along the second direction, the length of the first tab 012 is L 21耳 , the length of the pole piece body 011 is L 20 , meet: 30% L 20 ≤L 21耳 ≤50% L 20 Along the second direction, the first electrode tab 012 and the second electrode tab 013 are spaced apart.

[0256] In this embodiment, by using the aforementioned electrode piece 001, the electrode assembly 002 can have a larger tab area, thereby increasing the conduction path of electrons on the tab 014, thereby increasing the current collecting area of the electrode piece 001. In this way, the current collecting capacity of the electrode assembly 002 is improved.

[0257] See also Figure 8 , Figure 8 003 is a schematic diagram of the structure of a battery cell 003 provided in an embodiment of the present application. The embodiment of the present application provides a battery cell 003, and the battery cell 003 includes the aforementioned electrode assembly 002.

[0258] It can be understood that the battery cell 003 further includes a shell 031 and a cover plate 032. The shell 031 and the cover plate 032 cover each other to form a receiving cavity, and the electrode assembly 002 is disposed in the receiving cavity.

[0259] In this embodiment, by adopting the aforementioned electrode assembly 002 , the current transmission inside the battery cell 003 can be made smoother, the charging and discharging efficiency of the battery cell 003 can be higher, and the energy loss can be reduced.

[0260] In addition, by using the aforementioned electrode assembly 002 , the electrode piece 001 of at least one polarity of the battery cell 003 can output the same polarity at both ends, thereby improving the operability of the electrical connection of the battery cell 003 .

[0261] See also Figure 9 , Figure 9 FIG2 is a schematic diagram of the structure of a battery pack 004 provided in an embodiment of the present application. The embodiment of the present application provides a battery pack 004, which includes a battery box 041 and the aforementioned battery cells 003. The battery box 041 has a receiving cavity. Multiple battery cells 003 are disposed in the receiving cavity.

[0262] In this embodiment, by adopting the aforementioned battery cell 003 , the current transmission inside the battery pack 004 can be made smoother, the charging and discharging efficiency of the battery pack 004 can be higher, and the energy loss can be reduced.

[0263] See also Figure 10 , Figure 10 005 . The embodiment of the present application provides an electric device 005 , which includes the aforementioned battery cell 003 or the aforementioned battery pack 004 , and the battery cell 003 or the battery pack 004 supplies power to the electric device 005 .

[0264] It is understood that the electrical equipment 005 includes, but is not limited to, electric toys, electric tools, battery-powered vehicles, cars, ships, spacecraft, and the like. Electric toys may include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys. Spacecraft may include airplanes, rockets, space shuttles, and spacecraft. Cars may include gasoline-powered cars, gas-powered cars, and new energy vehicles.

[0265] In this embodiment, by adopting the aforementioned battery pack 004 , the charging efficiency of the electric device 005 can be improved, the energy utilization rate of the electric device 005 can be improved, and the energy loss of the electric device 005 can be reduced.

[0266] The above is a detailed introduction to the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of the present application. At the same time, for those skilled in the art, based on the ideas of the present application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A pole piece, characterized in that: include: The pole piece body has a first side and a second side that are oppositely arranged in a first direction; The tab includes a first tab and a second tab, wherein the first tab is arranged on the first side, and the second tab is arranged on the second side.

2. The pole piece according to claim 1, characterized in that: In the second direction, the pole piece body has a pole piece head end and a pole piece tail end; in the second direction, the second pole tab is arranged farther away from the pole piece head end than the first pole tab.

3. The pole piece according to claim 2, characterized in that: In the second direction, the second pole tab has a second pole tab head end close to the pole piece head end, and the second pole tab head end and the pole piece head end are spaced apart.

4. The pole piece according to claim 3, characterized in that: Along the second direction, the distance between the second tab end and the pole piece end is L 12头 The length of the pole piece body is L 10 , meet: 7% L 10 ≤L 12头 ≤20%L 10 .

5. The pole piece according to claim 4, characterized in that: Along the second direction, the length of the second tab is L 12耳 , meet: 60% L 10 ≤L 12耳 ≤80%L 10 .

6. The pole piece according to claim 3, characterized in that: Along the second direction, the distance between the second tab end and the pole piece end is L 12头 The length of the pole piece body is L 10 , meet: 30% L 10 ≤L 12头 ≤40%L 10 .

7. The pole piece according to claim 6, characterized in that: Along the second direction, the length of the second tab is L 12耳 , satisfying: L 12耳 =35%L 10 ~60%L 10 .

8. The pole piece according to any one of claims 2 to 7, characterized in that: Along the first direction, the first electrode tab and the second electrode tab are at least partially arranged opposite to each other.

9. The pole piece according to claim 8, characterized in that: Along the first direction, the ends of the first and second pole tabs close to each other are arranged opposite to each other, the end of the first pole tab away from the second pole tab is staggered with the second pole tab, and the end of the second pole tab away from the first pole tab is staggered with the first pole tab.

10. The pole piece according to claim 8, characterized in that: The pole piece has positive polarity.

11. The pole piece according to any one of claims 2 to 7, characterized in that: In the second direction, the second pole tab has a second pole tab tail end close to the pole piece tail end, and the second pole tab tail end is spaced apart from the pole piece tail end.

12. The pole piece according to claim 11, characterized in that: Along the second direction, the distance between the tail end of the second tab and the tail end of the pole piece is L 12尾 The length of the pole piece body is L 10 , satisfying: 0<L 12尾 ≤33%L 10 .

13. The pole piece according to any one of claims 2 to 7, characterized in that: In the second direction, the first tab has a first tab head end close to the pole piece head end and a first tab tail end close to the pole piece tail end; Along the second direction, the tail end of the first pole tab and the tail end of the pole piece are spaced apart; And / or, along the second direction, the first pole tab head end and the pole piece head end are spaced apart.

14. The pole piece according to claim 13, characterized in that: Along the second direction, the distance between the tail end of the first tab and the tail end of the pole piece is L 11尾 The length of the pole piece body is L 10 , satisfying: L 11尾 =60%L 10 ~78%L 10 .

15. The pole piece according to claim 13, characterized in that: Along the second direction, the distance between the first tab end and the pole piece end is L 11头 The length of the pole piece body is L 10 , satisfying: L 11头 =7%L 10 ~20%L 10 .

16. The pole piece according to claim 13, characterized in that: Along the second direction, the length of the first tab is L 11耳 The length of the pole piece body is L 10 , satisfying: L 11耳 =15%L 10 ~20%L 10 .

17. The pole piece according to claim 1, characterized in that: In the second direction, the pole piece body has a pole piece head end and a pole piece tail end; in the second direction, the second pole tab is arranged closer to the pole piece head end than the first pole tab.

18. The pole piece according to claim 17, characterized in that: In the second direction, the second pole tab has a second pole tab head end close to the pole piece head end, and the second pole tab head end and the pole piece head end are spaced apart.

19. The pole piece according to claim 18, characterized in that: Along the second direction, the distance between the second tab end and the pole piece end is L 22头 The length of the pole piece body is L 20 , satisfying: L 22头 =7%L 20 ~20%L 20 .

20. The pole piece according to claim 17, characterized in that: Along the second direction, the second pole tab has a second pole tab tail end close to the pole piece tail end, and the second pole tab tail end and the pole piece tail end are spaced apart.

21. The pole piece according to claim 20, characterized in that: Along the second direction, there is a distance L between the tail end of the second tab and the tail end of the pole piece. 22尾 The length of the pole piece body is L 20 , satisfying: L 22尾 =60L 20 ~78%L 20 .

22. The pole piece according to claim 17, characterized in that: Along the second direction, the length of the second tab is L 22耳 The length of the pole piece body is L 20 , satisfying: L 22耳 =15%L 20 ~20%L 20 .

23. The pole piece according to any one of claims 17 to 22, characterized in that: In the second direction, the first tab has a first tab head end close to the pole piece head end and a first tab tail end close to the pole piece tail end; Along the second direction, the tail end of the first pole tab and the tail end of the pole piece are spaced apart; And / or, along the second direction, the first pole tab head end and the pole piece head end are spaced apart.

24. The pole piece according to claim 23, characterized in that Along the second direction, the distance between the first tab end and the pole piece end is L 21头 The length of the pole piece body is L 20 , meet: 40% L 20 ≤L 21头 ≤50%L 20 .

25. The pole piece according to claim 23, characterized in that: Along the second direction, the distance between the tail end of the first tab and the tail end of the pole piece is L 21尾 The length of the pole piece body is L 20 , satisfying: 0<L 21尾 ≤30%L 20 .

26. The pole piece according to claim 23, characterized in that Along the second direction, the length of the first tab is L 21耳 The length of the pole piece body is L 20 , meet: 30% L 20 ≤L 21耳 ≤50%L 20 .

27. The pole piece according to any one of claims 17 to 22, characterized in that: Along the second direction, the first electrode tab and the second electrode tab are spaced apart.

28. The pole piece according to claim 27, characterized in that: The pole piece has a negative polarity.

29. The pole piece according to any one of claims 1 to 7 or any one of claims 17 to 22, characterized in that: The pole piece includes a coating area coated with an active material and a non-coating area not coated with the active material. The pole piece body is arranged in the coating area, and the pole tab is arranged in the non-coating area.

30. The pole piece according to any one of claims 1 to 7 or any one of claims 17 to 22, characterized in that: The tabs are die-cut tabs.

31. The pole piece according to claim 30, characterized in that The die-cutting width of the tab is W, which satisfies 2mm≤W≤6mm.

32. The pole piece according to claim 30, characterized in that The die-cutting angle of the tab is α, which satisfies 55°≤α≤85°.

33. The pole piece according to claim 30, characterized in that The die-cutting height of the tab is H, which satisfies: 5mm≤H≤7.5mm.

34. An electrode assembly, characterized in that Comprising a pole piece as described in any one of claims 1-29.

35. A battery cell, characterized in that: Comprising the electrode assembly of claim 34.

36. A battery pack, characterized in that: include: A battery box having a receiving cavity; And, as described in claim 35, there are multiple battery cells, and the multiple battery cells are arranged in the accommodating cavity.

37. An electrical device, characterized in that: It includes the battery cell as described in claim 35 or the battery pack as described in claim 36, and the battery cell or battery pack supplies power to the electrical device.

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