Battery

Abstract

The present invention relates to the technical field of batteries, and discloses a battery, which comprises: a laminated cell, which comprises a plurality of pole pieces stacked layer by layer along a first direction, each pole piece comprises a pole piece body and a pole lug, the pole lug is led out from the pole piece body along a second direction, the size of the pole piece body in a third direction is L1 mm, and the size of the pole piece body in a fourth direction is L1 mm; the size of the tab in the third direction is L2 mm, and L1-L2 is more than or equal to 20 and less than or equal to 120; wherein the first direction, the second direction and the third direction are intersected pairwise. According to the invention, the size range of the cut part is limited, so that the overcurrent requirement of the tab is met, the adsorption or clamping stability of the cutting operation can be ensured, the positioning precision of the cutting operation is high, the yield of the tab is improved, and the overall yield of the laminated battery is further improved.

Description

[0001] This application is a divisional application of the patent application with application number "202510150328X" and titled "Battery", filed on February 11, 2025. TECHNICAL FIELD

[0002] The present application relates to the technical field of batteries, in particular to a battery. BACKGROUND

[0003] In the production and manufacturing process of the laminated battery, the tab area on the pole piece needs to be cut to form the tab. However, the positioning accuracy of the cutting operation in the prior art is poor, which leads to a low yield of the tab and affects the overall yield of the laminated battery. SUMMARY

[0004] The purpose of the present application is to provide a battery that can improve the positioning accuracy of the cutting operation and improve the yield of the tab.

[0005] In order to achieve the above-mentioned purpose, one aspect of the present application provides a battery, characterized in that it comprises:

[0006] The laminated battery cell comprises a plurality of pole pieces stacked in a first direction, each pole piece comprising a pole piece body and a tab, the tab being drawn from the pole piece body in a second direction, the size of the pole piece body in a third direction being L1 mm, and the size of the tab in the third direction being L2 mm, satisfying: 20≤L1–L2≤120.

[0007] The first direction, the second direction and the third direction are perpendicular to each other.

[0008] The above-mentioned technical solution has the following beneficial effects compared with the prior art:

[0009] The battery of one aspect of the present application comprises a laminated battery cell, the laminated battery cell comprises a plurality of pole pieces, each pole piece comprising a pole piece body and a tab, by limiting the size difference between the size L1 mm of the pole piece body in the third direction and the size L2 mm of the tab in the third direction, the stability of the cutting operation adsorption or clamping, the positioning accuracy of the cutting operation, the yield of the tab and the overall yield of the laminated battery are improved. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 is a structural schematic diagram of the laminated battery cell of the embodiment of the present application.

[0011] Figure 2 is a structural schematic diagram of the negative pole piece of the embodiment of the present application.

[0012] Figure 3 isFigure 2 An enlarged schematic view of the middle B.

[0013] Figure 4 is a structural schematic view of the positive electrode sheet of the embodiment of the present application.

[0014] Figure 5 is Figure 4 An enlarged schematic view of the middle C.

[0015] Figure 6 is Figure 4 An enlarged schematic view of another embodiment of the middle C.

[0016] Figure 7 is a schematic view of the electrode sheet and the reinforcing rib of the embodiment of the present application.

[0017] Figure 8 is Figure 7 A schematic view of the reinforcing rib from another angle.

[0018] Figure 9 is a structural schematic view of the battery of the embodiment of the present application.

[0019] In the figure, 1, the laminated sheet cell; 2, the shell; 3, the cover plate;

[0020] 11, the electrode sheet; 11a, the positive electrode sheet; 11b, the negative electrode sheet; 111, the electrode sheet body; 112, the tab; 1121, the reinforcing rib; Z, the first direction; X, the second direction; Y, the third direction. DETAILED DESCRIPTION

[0021] The specific embodiments of the present application will be further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application, but are not used to limit the scope of the present application.

[0022] In the description of the present application, it should be noted that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0023] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0024] Furthermore, in the description of the present invention, unless otherwise specified, “plurality” means two or more.

[0025] For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] Please refer to Figure 1 A battery according to an embodiment of the present invention includes a laminated battery core 1. The laminated battery core 1 includes a plurality of pole pieces 11 stacked in layers along a first direction Z. Each pole piece 11 includes a pole piece body 111 and a pole tab 112. The pole tab 112 is extended in a second direction X. The dimension of the pole piece body 111 in a third direction Y is L1 mm, and the dimension of the pole tab 112 in the third direction Y is L2 mm, satisfying the following conditions: 20≤L1–L2≤120.

[0027] The first direction Z, the second direction X, and the third direction Y intersect with each other.

[0028] In this embodiment, the height direction of the laminated battery core 1 is the first direction Z, the length direction of the laminated battery core 1 is the second direction X, and the width direction of the laminated battery core 1 is the third direction Y. Vertical refers to a state with an angle of 85° to 95°.

[0029] The stacking of the positive electrode sheets 11 a and the negative electrode sheets 11 b is called a laminate. The electrode sheets 11 of the same polarity are discontinuous. A separator is provided between the positive electrode sheets 11 a and the negative electrode sheets 11 b to separate them, thereby forming a laminated battery cell 1 .

[0030] The laminated battery cell 1 has the characteristics of low internal resistance, good heat dissipation performance, uniform mechanical stress distribution and high energy density. Compared with the wound battery cell, the laminated battery cell 1 has a higher internal space utilization rate and the risk of lithium plating of the battery electrode 11 is relatively small.

[0031] The positive and negative electrodes 11a and 11b are electrodes 11 with opposite polarities. The battery cell operates by transferring metal ions between the positive and negative electrodes 11a and 11b. The battery cell's cycle involves the transfer of metal ions from the positive electrode 11a to the negative electrode 11b, and then from the negative electrode 11b to the positive electrode 11a.

[0032] The diaphragm is used as an insulating layer to prevent the positive tab 11a and the negative tab 11b from contacting to cause internal short circuit of the battery, and is used as a semi-permeable layer to prevent large molecules from passing through while allowing small volume charged ions to pass through.

[0033] The tab 112 is electrically connected with the tab 11, wherein the positive tab 112 is electrically connected with the positive tab 11a, and the negative tab 112 is electrically connected with the negative tab 11b. The battery cell realizes charging and discharging through the positive tab 112 and the negative tab 112. The tab 11 includes a current collector and an active material layer, and the active material layer is coated on the surface of the current collector. When the tab 11 is the positive tab 11a, the material of the current collector can be aluminum, and the material of the active material layer can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganate, etc. When the tab 11 is the negative tab 11b, the material of the current collector can be copper, and the material of the active material layer can be carbon or silicon, etc.

[0034] In the embodiment, the laminated battery cell 1 includes a plurality of tabs 11, and the plurality means no less than one.

[0035] In the cutting process, the cutting area needs to be positioned first, such as being adsorbed or clamped to fix the cutting area, and then the tab 112 is cut by a cutter to realize the separation of the cutting part and the tab 112 area.

[0036] When 20≤L1–L2≤120 is met, the overcurrent demand of the tab 112 can be met while providing space for positioning the cutting area, ensuring the stability of adsorption or clamping in the cutting operation, improving the positioning accuracy of the cutting operation, improving the yield of the tab 112, and further improving the overall yield of the laminated battery. If L1–L2 is too small, the adsorption force or clamping force will be insufficient, the cutting area will not be easily positioned, the positioning and cutting accuracy of the tab 112 will be affected, the cutting yield of the tab 112 will be reduced, the cut tab 11 and the tab 112 area will be stuck, or there will be more burrs during cutting, the tab 112 will be torn, the cutting size of the tab 112 will be uneven, etc. If L1–L2 is too large, the size of the tab 112 after cutting will be small, which cannot meet the overcurrent demand of the tab 112. When the battery is fast-charged at a large rate, the tab 112 generates a large amount of heat, the internal resistance of the battery is too large, and the battery has safety risks such as thermal control, and the overall charging and discharging rate of the battery is affected.

[0037] Preferably, L1–L2 can take values of 20, 35, 50, 66, 84, 100, 113, 120, etc.

[0038] When measuring the sizes L1 and L2, a general length measuring tool can be used, such as a ruler or a tape measure.

[0039] Specifically, when measuring L1, taking one end edge of the pole piece body 111 in the third direction Y as a reference edge, the distance between the reference edge and the other edge is measured along the third direction Y by a length measuring tool, and the size of the pole piece body 111 in the third direction Y is obtained by measuring multiple times and taking the average value, L1 mm.

[0040] When measuring L2, taking one end edge of the tab 112 in the third direction Y as a reference edge, the distance between the reference edge and the other edge is measured along the third direction Y by a length measuring tool, and the size of the tab 112 in the third direction Y is obtained by measuring multiple times and taking the average value, L2 mm.

[0041] In some embodiments, the size of the tab 112 in the first direction Z is H mm, and the hardness of the tab 112 is A HRB, which satisfies: 0.0003≤(H*A) / (L1–L2)≤0.08.

[0042] When this range is satisfied, the overcurrent requirement of the tab 112 can be met while ensuring the adsorption force or clamping force of the cutting operation. The size of the tab 112 in the first direction Z, that is, the thickness of the tab 112, and the hardness of the tab 112, all have higher requirements on the adsorption force or clamping force.

[0043] In addition to the need to control the size of L1–L2 within the range of 20 mm-120 mm, the thickness and hardness of the tab 112 simultaneously affect the overall overcurrent of the tab 112 and the yield of the tab 112 cutting. Therefore, when the overcurrent requirement is met, the cutting efficiency of the battery tab 112 can be ensured by controlling the thickness, hardness and L1–L2 of the tab 112, avoiding phenomena such as adhesion between the cut-off pole piece 11 and the tab 112 area, or more burrs during cutting, tearing of the tab 112, uneven cutting size of the tab 112, etc.

[0044] If (H*A) / (L1–L2) is too small, the overcurrent capacity of the tab 112 cannot be guaranteed, and the tab 112 is prone to folding, which can cause virtual welding when the tab 112 and the pole are welded, affecting the welding quality and thus the overcurrent capacity between the tab 112 and the pole; if (H*A) / (L1–L2) is too large, it will result in insufficient adsorption force or clamping force during positioning of the cutting operation, insufficient area for adsorbing the tab 112, unstable support of the tab 112, adhesion during cutting of the tab 112, or more burrs during cutting, tearing of the tab 112, uneven cutting size of the tab 112, and the tab 112 occupying a larger space after cutting, affecting the space utilization of the battery, and thus resulting in low energy density and difficulty in subsequent bending of the tab 112.

[0045] Preferably, (H*A) / (L1-L2) can take the values 0.0003, 0.1, 0.24, 0.36, 0.49, 0.75, 0.08, etc.

[0046] In measuring the dimension H, a common length measuring tool can be used, such as a ruler, a tape measure, etc.

[0047] In measuring H, one end face of the tab 112 in the first direction Z is taken as a reference face, the distance between the reference face and the other end face is measured along the first direction Z by a length measuring tool, the dimension H mm of the tab 112 in the first direction Z is obtained by measuring multiple times and taking an average value.

[0048] In measuring A, the method for testing hardness in the national standard can be used for measurement.

[0049] To support the rationality of the above numerical range, the present embodiment also tests the cutting yield and the overcurrent capacity of the battery that meets the above numerical range.

[0050] Cutting yield test method: take 100 pieces of pole pieces, use a 300w air-cooled infrared nanosecond laser of ipg brand as a tab cutting device, and perform a tab cutting process on each pole piece, after each pole piece completes the tab cutting, measure the maximum size X of burrs or metal chips of the tab cutting edge. Count the number N of pole pieces with X≤20μm in 100 pole pieces, if N≥90, the cutting yield is determined to be good, if 80≤N<90, the cutting yield is determined to be qualified, if N<80, the cutting yield is determined to be unqualified.

[0051] Overcurrent capacity test method: at 25℃, the lithium ion batteries prepared in the examples and the comparative examples are tested according to the following procedure.

[0052] For lithium iron phosphate batteries:

[0053] 1) Connect the pole to the temperature touch sensor, charge at a constant current of 4C rate to 3.65V, and charge at a constant voltage until the current drops to 0.05C, and record the temperature of the pole area during the charging process.

[0054] 2) Obtain the maximum temperature T of the pole area during the charging process, when the maximum temperature T of the pole area is ≤45℃, it is good, when 45℃<T≤65℃, it is qualified, when T>65℃, it is unqualified.

[0055] For other batteries such as ternary batteries other than lithium iron phosphate batteries:

[0056] 1) Connect the pole to the temperature touch sensor, charge at a constant current of 4C rate to 4.25V, and charge at a constant voltage until the current drops to 0.05C, and record the temperature of the pole area during the charging process.

[0057] 2) Obtain the maximum temperature T of the pole region during the charging process. When the maximum temperature T of the pole region is ≤45℃, it is good; when 45℃

[0058] The test parameters and index data of each group are shown in Table 1.

[0059] Table 1

[0060]

[0061] As can be seen from the data in Table 1, for the batteries that all satisfy the value ranges of L1-L2 and (H*A) / (L1-L2) and the value ranges of L1, L2, H and A, that is, Examples 1-6, the tabs 112 have good overcurrent capacity, high cutting accuracy, good tab 112 cutting yield, and thus improve the overall yield of the stacked battery. For the batteries that all satisfy the value ranges of L1-L2 and (H*A) / (L1-L2), but the value of H is too small and the value of A is too large, that is, Examples 7-8, the overcurrent capacity and cutting yield are both qualified test results. For the batteries that do not satisfy the value range of L1-L2, that is, Comparative Examples 1-4, at least one of the overcurrent capacity and the cutting yield cannot obtain a qualified test result.

[0062] In some embodiments, the thickness H of the tab 112 and the hardness A of the tab 112 satisfy: 0.021≤H*A≤1.9 and / or 0.002≤H≤0.02 and / or 10≤A≤100.

[0063] And / or it means that the three ranges can be any one of them, or any two of them, or all three of them.

[0064] When the above ranges are satisfied, the overcurrent capacity of the tab 112 is satisfied, and the tab 112 is prevented from being easily folded, while ensuring the adsorption force or clamping force of the cutting operation.

[0065] If H*A is too small, it is easy to fold, the welding quality of the tab 112 and the pole is poor, which affects the overcurrent capacity of the tab 112, and also causes the internal resistance of the tab 112 to be too large due to heat generation, which affects the charge and discharge capacity of the battery. If H*A is too large, the tab 112 will have burr and tearing problems formed during cutting, and it is not easy to bend. The adsorption force or clamping force during positioning of the cutting operation is insufficient, and the space occupied is too large, which also affects the energy density of the battery.

[0066] Preferably, H*A can take values of 0.021, 0.07, 0.01, 0.05, 0.2, 0.6, 1, 1.32, 1.48, 1.59, 1.84, 1.9, etc.

[0067] If H is too small, the overcurrent capacity of the tab 112 is insufficient, and when the battery is subjected to large-rate fast charging, the tab 112 generates a large amount of heat, the battery has a large internal resistance, and the battery has safety risks such as thermal control, and the overall charging and discharging rate of the battery is affected; if H is too large, the tab 112 occupies a large space, affecting the space utilization rate of the battery, the energy density of the battery is small, and the adsorption force or clamping force during positioning of the cutting operation is insufficient.

[0068] Preferably, H can take values of 0.002, 0.034, 0.085, 0.12, 0.15, 0.19, 0.02, etc.

[0069] If A is too small, the tab 112 is prone to folding, which can cause virtual welding when the tab 112 and the pole are welded, affecting the welding quality and further affecting the overcurrent capacity between the tab 112 and the pole; if A is too large, the tab 112 has more burrs when cutting, the tab 112 is torn, the cutting size of the tab 112 is not uniform, the tab 112 is not easy to bend subsequently, and the adsorption force or clamping force during positioning of the cutting operation is insufficient.

[0070] Preferably, A can take values of 10, 15, 30, 55, 69, 84, 97, 100, etc.

[0071] In some embodiments, the dimension L1 of the tab body 111 in the third direction Y is also satisfied: 50≤L1≤150.

[0072] If L1 is too small, the adsorption force or clamping force during positioning of the cutting operation is insufficient; if L1 is too large, the overcurrent capacity of the tab 112 is insufficient.

[0073] Preferably, L1 can take values of 50, 65, 87, 101, 116, 125, 137, 142, 150, etc.

[0074] In some embodiments, the dimension L2 of the tab 112 in the third direction Y is also satisfied: 20≤L2≤80.

[0075] If L2 is too small, the overcurrent capacity of the tab 112 is insufficient; if L2 is too large, the adsorption force or clamping force during positioning of the cutting operation is insufficient.

[0076] Preferably, L2 can take values of 20, 26, 39, 54, 64, 78, 80, etc.

[0077] In some embodiments, the distance between the edge of the first end of the tab 112 in the third direction Y and the edge of one end of the tab body 111 on the same side in the third direction Y is d1 mm, the distance between the edge of the second end of the tab 112 in the third direction Y and the edge of one end of the tab body 111 on the same side in the third direction Y is d2 mm, and the following conditions are met: d1≠0 and d2≠0, d1 / d2≤0.9 or d1 / d2≥1.1, and 20≤L1-L2≤118.

[0078] d1≠0 and d2≠0, and the edge of the tab 112 is not flush with any side edge of the tab body 111 in the third direction Y.

[0079] The tab 112 can not be arranged at the center of the tab body 111. When the tab 112 is arranged offset, the size of the cutting area on the offset side is small, the suction force or clamping force of the cutting operation is not easy to meet, and the accurate cutting position is not easy to position accurately. When the above range is met, the suction force or clamping force of the cutting operation can be met, the stability of the suction or clamping of the cutting operation is ensured, and the positioning accuracy of the cutting operation is improved.

[0080] Preferably, L1-L2 can take values such as 20, 24, 41, 62, 81, 98, 107, 115, 118, etc.

[0081] When measuring the measurement sizes d1 and d2, a general length measuring tool can be used, such as a ruler, a tape measure, etc.

[0082] Specifically, when measuring d1, in the third direction Y, taking the edge of the first end of the tab body 111 as the reference edge, the distance between the edge of one end of the tab 112 close to the reference edge and the reference edge is measured by a length measuring tool, and the average value is obtained by measuring multiple times, to obtain the distance d1 mm between the edge of the first end of the tab 112 in the third direction Y and the edge of one end of the tab body 111 on the same side in the third direction Y.

[0083] When measuring d2, in the third direction Y, taking the edge of the second end of the tab body 111 as the reference edge, the distance between the edge of one end of the tab 112 close to the reference edge and the reference edge is measured by a length measuring tool, and the average value is obtained by measuring multiple times, to obtain the distance d2 mm between the edge of the second end of the tab 112 in the third direction Y and the edge of one end of the tab body 111 on the same side in the third direction Y.

[0084] The first end and the second end are the two ends of the tab body 111 in the third direction Y. In this embodiment, the first end is the end of the tab body 111 on the side offset from the tab 112.

[0085] The distance d1 mm between the edge of the first end of the tab 112 in the third direction Y and the edge of one end of the tab body 111 on the same side in the third direction Y also satisfies 20≤d1≤80.

[0086] When the above range is satisfied, the cutting region with a smaller side dimension biased to one side of the tab 112 can also have sufficient suction force or clamping force to ensure the stability of the suction or clamping in the cutting operation, and the cut region is not too small, reducing the difficulty of accurately positioning the cutting position. In addition, the position of the tab 112 is not too biased, preventing uneven flow problems.

[0087] Preferably, d1 can take values of 20, 32, 48, 53, 62, 71, 80, etc.

[0088] In some embodiments, d1≠0 and d2≠0, and when 0.9

[0089] d1≠0 and d2≠0, and the edge of the tab 112 is not flush with any side edge of the tab body 111 in the third direction Y.

[0090] When 0.9

[0091] Preferably, L1-L2 can take values of 22, 29, 32, 47, 55, 67, 89, 109, 120, etc.

[0092] In some embodiments, d1=0 or d2=0, and 22≤L1–L2≤118.

[0093] d1=0 or d2=0, and the edge of the tab 112 is flush with one side edge of the tab body 111 in the third direction Y.

[0094] In this case, the flow-through effect of the tab 112 is poor, and when the tab 112 is cut, the area cut off from the tab 112 with one side flush is larger than the cutting region on both sides of the tab 112 and the tab body 111 in the third direction Y, and it is more difficult to meet the clamping force or suction force required in the cutting operation. Therefore, when 22≤L1–L2≤118 is satisfied, the suction force or clamping force of the cutting operation can be met to ensure the stability of the suction or clamping in the cutting operation.

[0095] Preferably, L1-L2 can take values 22, 33, 57, 62, 71, 88, 108, 115, 118, etc.

[0096] In some embodiments, the dimension of the pole piece body 111 in the second direction X is L3 mm, which satisfies: when 250≤L3<350, 20≤L1-L2≤118; when 350≤L3<550, 20≤L1-L2≤116; and when L3≥550, 20≤L1-L2≤114.

[0097] L3 is the length of the pole piece body 111. In order to ensure the adsorption force or clamping force in the cutting operation, different requirements are provided for the space of the positioning of the cutting area in different length ranges. The larger the size of the pole piece 11, the greater the flow demand of the tab 112, and the larger the size of the flow area of the tab 112. The larger the value of L3, the more difficult it is to position the tab 112 during the cutting operation, and a larger adsorption force or clamping force is required.

[0098] When the above ranges are met, for different sizes of the pole piece 11, sufficient adsorption force or clamping force can be provided for the cutting operation, facilitating the smooth progress of the cutting operation while meeting the flow requirements of the tabs 112 of different sizes. However, the larger the value of L3, the larger the pole piece body 111, and the more active substances on the pole piece body 111, the larger the flow area required by the tab 112 to ensure the flow capacity of the tab 111.

[0099] Preferably, when 250≤L3<350, L1-L2 can take values 20, 25, 39, 44, 69, 85, 92, 107, 118, etc.; when 350≤L3<550, L1-L2 can take values 20, 33, 41, 65, 74, 97, 100, 114, 116, etc.; and when L3≥550, L1-L2 can take values 20, 36, 51, 67, 77, 94, 107, 114, etc.

[0100] In some embodiments, please refer to Figure 6 , the connection between the pole piece body 111 and the tab 112 is a right-angle transition, which satisfies: 20≤L1-L2≤118. Preferably, L1-L2 can take values 20, 21, 37, 58, 66, 79, 81, 99, 106, 112, 118, etc.

[0101] The right-angle transition structure makes it difficult for the cutting section and the tab 112 area to stick together during the cutting operation, and the cutting efficiency is relatively high. However, the right-angle transition structure results in a poorer flow area of the tab 112 compared to the round-angle transition. By setting L1-L2 to take values within the above range, the flow capacity of the tab 112 can be improved while not affecting the yield of the pole piece 11.

[0102] In some embodiments, referring to Figure 5 , the connection between the pole piece body 111 and the tab 112 is rounded, and satisfies: 22≤L1–L2≤120. Preferably, L1-L2 can take values of 22, 23, 48, 53, 76, 88, 93, 109, 115, 120, etc.

[0103] The structure of the rounded transition has stronger flow capacity than the structure of the right-angle transition, but is prone to adhesion during cutting operation, and thus needs to satisfy a larger cutting size to avoid adhesion. By the structure of the rounded transition and setting L1–L2 to take values in the above range, the problem of poor flow capacity due to the excessively large cutting of the tab 112 can be further compensated. At the same time, the adsorption force or clamping force cannot be too small to ensure the stability of adsorption or clamping during cutting operation, and in addition, the structure of the rounded transition also makes the position of the transition not prone to tearing.

[0104] In some embodiments, the radius of the rounded corner at the connection between the pole piece body 111 and the tab 112 is R mm, and satisfies: 1≤R≤10. Preferably, R can take values of 1, 3, 6, 8, 10, etc.

[0105] When satisfying the above range, the flow requirement of the tab 112 can be met, and the problem of serious adhesion during cutting operation can be avoided. If R takes a too small value, the problem of not meeting the flow requirement will occur, and if R takes a too large value, the problem of serious adhesion during cutting operation will occur.

[0106] In some embodiments, referring to Figure 7 , the tab 112 is provided with a reinforcing rib 1121, and satisfies: 20≤L1–L2≤118.

[0107] The setting of the reinforcing rib 1121 can improve the strength of the tab 112. The reinforcing rib 1121 can be set as regular polygons such as triangles, quadrilaterals, and ellipses, or can be set as irregular polygons. The reinforcing rib 1121 can be separately made and then welded, pasted, or connected in other ways to the tab 112, or can be integrally formed with the tab 112.

[0108] Preferably, L1-L2 can take values of 20, 22, 49, 51, 62, 77, 81, 93, 106, 115, 118, etc.

[0109] In the embodiment, the reinforcing ribs 1121 protrude from the surface of the tab 112, and the reinforcing ribs 1121 are in the shape of a strip and / or a circle. In other words, on the same tab 112, all the reinforcing ribs 1121 are in the shape of a circle, or all the reinforcing ribs 1121 are in the shape of a strip, or part of the reinforcing ribs 1121 are in the shape of a circle and part of the reinforcing ribs 1121 are in the shape of a strip. In addition, the reinforcing ribs 1121 are pressed from the tab 112 to form an embossed form.

[0110] Please refer to Figure 8 The height t of the reinforcing ribs 1121 protruding from the surface of the tab 112 satisfies: 0.001≤t≤0.018.

[0111] When the above range is satisfied, the efficiency of cutting the tab 112 can be improved, the burrs of the tab 112 can be reduced, the strength of the tab 112 itself can be ensured, and the problem of adhesion in the cutting process can be reduced. If t is too small, the strength of the tab 112 itself cannot be guaranteed, the adsorption force or clamping force is also weak, and the problem of adhesion is prone to occur. If t is too large, the tab 112 is not easy to cut during cutting operation, which affects the cutting efficiency, and the cut tab 112 also has more burrs.

[0112] Preferably, t can be 0.001, 0.007, 0.011, 0.013, 0.014, 0.018, etc.

[0113] In some embodiments, the pole piece body 111 is in a polygonal shape, and two adjacent edges of the pole piece body 111 form an edge angle, and the edge angle is a right angle, and satisfies: 20≤L1–L2≤118.

[0114] In the embodiment, the pole piece body 111 is in a rectangular shape.

[0115] The structure of the right angle is not easy to cause adhesion during cutting operation, has high cutting efficiency, and does not require a large adsorption force or clamping force, so that the above range can provide sufficient adsorption force or clamping force.

[0116] Preferably, L1–L2 can be 20, 23, 49, 59, 61, 72, 85, 97, 101, 112, 118, etc.

[0117] In some embodiments, the pole piece body 111 is in a polygonal shape, and two adjacent edges of the pole piece body 111 form an edge angle, and the edge angle is a round angle, and satisfies: 22≤L1–L2≤120.

[0118] In the embodiment, the pole piece body 111 is in a rectangular shape.

[0119] The rounded structure can avoid the edge tip of the tab 112 from discharging, but the cutting operation is prone to adhesion, so the size of the cutting is increased to ensure the adsorption force or clamping force, thereby ensuring the stability of the cutting operation.

[0120] Preferably, L1-L2 can be 22, 27, 37, 46, 50, 71, 80, 91, 110, 120, etc.

[0121] In some embodiments, the tab 11 includes a positive tab 11a and a negative tab 11b, the edge of the tab body 111 of the positive tab 11a is rounded, and the edge of the tab body 111 of the negative tab 11b is a right angle, and the size of the negative tab 11b is larger than that of the positive tab 11a.

[0122] In the manufacturing process of the laminated battery cell 1, the negative electrode is arranged on the positive electrode, and through such a structure, the edge of the positive tab 11a can be prevented from piercing the separator and the negative electrode, thereby improving the yield of the laminated battery cell 1.

[0123] By setting the edge of the tab body 111 of the positive tab 11a to be rounded and the edge of the tab body 111 of the negative tab 11b to be a right angle, the adhesion of the tab 112 during cutting is avoided, and the insulation safety of the positive and negative tabs 11b is ensured, thereby reducing the risk of insulation short circuit failure caused by the right angle of the positive tab 11a piercing the separator and the negative tab 11b.

[0124] Please refer to Figure 9 The battery further includes a shell 2 and a cover plate 3, the shell 2 has an opening, the cover plate 3 is arranged on the opening, the cover plate 3 and the shell 2 form a containing space, and the laminated battery cell 1 is at least partially arranged in the containing space.

[0125] The laminated battery cell 1 can enter the inside of the shell 2 through the opening, the cover plate 3 arranged on the opening can make the containing space in a sealed state, the cover plate 3 is provided with an electrode column for electrically connecting the laminated battery cell 1 and the outside of the battery, and the cover plate 3 is further provided with a pressure relief mechanism for explosion when the battery is in thermal runaway.

[0126] The above only describes the preferred embodiments of the present application, and it should be pointed out that for ordinary skilled in the art, without departing from the technical principles of the present application, a number of improvements and replacements can be made, and these improvements and replacements should be considered as the protection scope of the present application.

Claims

1. A battery, characterized in that: include: A laminated battery cell, comprising a plurality of pole pieces stacked in layers along a first direction, the pole pieces comprising a pole piece body and a pole lug, the pole lug extending from the pole piece body along a second direction, the pole piece body having a dimension of L1 mm in a third direction, the pole lug having a dimension of L2 mm in the third direction, the distance between an edge of the pole lug at a first end in the third direction and an edge of an end of the pole piece body on the same side in the third direction being d1 mm, the distance between an edge of the pole lug at a second end in the third direction and an edge of an end of the pole piece body on the same side in the third direction being d2 mm, and the dimension of the pole piece body in the second direction being L3 mm; satisfying: d1≠0 and d2≠0, d1 / d2≤0.9 or d1 / d2≥1.1, 20≤L1–L2≤118, L3≤550; The first direction, the second direction and the third direction are perpendicular to each other.

2. The battery according to claim 1, wherein: A distance d1 mm between an edge of the first end of the electrode tab in the third direction and an edge of one end of the electrode body on the same side in the third direction also satisfies the following: 20≤d1≤80.

3. The battery according to claim 1, wherein: The dimension L1 mm of the pole piece body in the third direction also satisfies the following: 50≤L1≤150.

4. The battery according to claim 1, wherein: The dimension L2 mm of the tab in the third direction also satisfies the following: 20≤L2≤80.

5. The battery according to claim 1, wherein: The connection between the pole piece body and the pole ear has a right-angle transition, which satisfies the following conditions: 20≤L1–L2≤118.

6. The battery according to claim 1, wherein: The connection between the pole piece body and the pole ear has a rounded transition, which satisfies the following conditions: 22≤L1–L2≤118.

7. The battery according to claim 6, characterized in that: The radius of the fillet at the connection between the pole piece body and the pole ear is R mm, satisfying: 1≤R≤10.

8. The battery according to any one of claims 1, characterized in that: The tab is provided with reinforcing ribs, which satisfy: 20≤L1–L2≤118.

9. The battery according to claim 8, characterized in that: The reinforcing ribs protrude from the surface of the tab, and the shape of the reinforcing ribs is strip and / or circular.

10. The battery according to claim 9, characterized in that: The height of the reinforcing rib protruding from the surface of the tab is t mm, satisfying the following: 0.001≤t≤0.018.

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