A full-tab cylindrical lithium ion battery, a battery module and an electric device

Abstract

This application relates to a fully tabbed cylindrical lithium-ion battery, a battery module, and an electrical device. The fully tabbed cylindrical lithium-ion battery includes a casing, a core disposed inside the casing, and an electrolyte; the width W of the positive electrode coating area... p Width W of the negative electrode coating area n Satisfies: 1.008≤W n / W p ≤1.045; the equivalent impedance R of the positive terminal omnipolar collecting path. top The equivalent impedance R of the current collection path of the negative terminal omnipolar tab bot Satisfy: ΔR end =|R top -R bot |<0.35mΩ. This application identifies the equivalent impedance of the positive electrode current collector path and the equivalent impedance of the negative electrode current collector path, and by adjusting the ratio of the width of the positive electrode coating area to the width of the negative electrode coating area, it improves the axial thermal uniformity of the all-tab cylindrical lithium-ion battery, reduces the risk of local hot spots and end thermal aging, and improves the safety performance of the all-tab cylindrical lithium-ion battery.

Description

Technical Field

[0001] This application relates to the field of lithium-ion battery technology, specifically to cylindrical lithium-ion batteries, and more particularly to a multi-tab cylindrical lithium-ion battery, battery module, and electrical device. Background Technology

[0002] Cylindrical lithium-ion batteries need to balance capacity, internal resistance, thermal safety and cycle stability in high-rate discharge scenarios. The full-tab structure can reduce the electron transmission impedance along the length of the electrode and improve the rate output capability.

[0003] As the energy density requirements of electrical equipment for cylindrical lithium-ion batteries continue to increase, the height of cylindrical lithium-ion batteries is decreasing. If a considerable capacity is to be maintained, the assembly allowance between the axial space of the casing, the width of the material area, the width of the empty foil area, the flattened end face, the current collector, and the welding path needs to be narrowed simultaneously. This makes the effective material loading per unit axial height, the end current collector load, and the distribution of local heat sources more sensitive.

[0004] CN114300786A discloses a cylindrical lithium battery with a steel shell structure that can improve energy output and reduce heat generation, and its manufacturing method. The method involves coatings on the surfaces of the steel shell and cap assembly in the cylindrical lithium battery with materials whose Seebeck coefficients differ from those of the steel shell and cap assembly materials. After the lithium battery generates heat during operation, according to the Seebeck effect, a thermoelectric electromotive force is generated between the steel shell coating and the junction of the steel shell material in the high-temperature zone of the battery's middle section and the cap assembly coating and the junction of the cap assembly material in the low-temperature zone of the upper section. This converts the heat energy generated during battery operation into electrical energy, thereby providing additional energy output and reducing heat generation.

[0005] CN121885782A discloses a method for manufacturing a fully tabbed cylindrical battery cell. The method involves die-cutting the uncoated current collector areas of both the positive and negative electrode sheets to form multiple unequally spaced tabs. These tabs are then wound to form a core, in which the tabs of the positive and negative electrode sheets overlap axially, and the tabs of the same layer of positive and negative electrode sheets also overlap axially. A hollow current collector is prepared, and its welding position is aligned and welded to the flattened tab groups on both sides of the core. The welded core is then placed into a casing, and sequentially subjected to electrolyte injection, formation, electrolyte replenishment, sealing nail welding, and capacity testing to obtain a fully tabbed cylindrical battery cell. This invention provides a method for manufacturing fully tabbed cylindrical batteries that shortens the electrolyte penetration path, reduces penetration resistance, and ensures high current carrying capacity and uniform current distribution.

[0006] CN209357816U discloses a busbar for a cylindrical lithium-ion battery with multiple tabs. The busbar is positioned at the lower end of the positive electrode cover, with an upper side and a lower side symmetrically arranged on both sides. A lower mounting plate with raised steps is located at the lower end of the positive electrode cover. The busbar's planar surface and the upper and lower sides increase the current-carrying area, effectively improving the rate performance of the battery and reducing heat generation.

[0007] Existing solutions can usually only indicate whether the cell has reached the overall capacity and overall thermal safety window, but it is difficult to explain whether there are local hot spots at the top, middle and bottom of the cell. Even if the overall maximum temperature is still within an acceptable range, there may still be risks of local thermal aging, lithium plating or interface impedance growth.

[0008] Therefore, there is a need for a cylindrical lithium-ion battery with good axial thermal uniformity and a lower risk of axial local hot spots. Summary of the Invention

[0009] To address the shortcomings of existing technologies, this application aims to provide a full-tab cylindrical lithium-ion battery, battery module, and electrical device. This application addresses the technical problem that reducing the height of a cylindrical lithium-ion battery, while maintaining a consistent capacity, leads to an increase in the effective material loading per unit axial height, resulting in increased end current collection load and consequently, greater sensitivity to localized heat sources. By identifying the equivalent impedances of the positive and negative full-tab current collection paths and controlling the difference between them to be less than 0.35 mΩ, combined with adjusting the ratio of the width of the positive to the negative electrode coating area, the axial thermal uniformity of the full-tab cylindrical lithium-ion battery is effectively improved, reducing the risk of localized hot spots and end-point thermal aging, thus enhancing the safety performance of the full-tab cylindrical lithium-ion battery.

[0010] To achieve this objective, the present application adopts the following technical solution: In a first aspect, this application provides a full-tab cylindrical lithium-ion battery, comprising a casing, a core disposed inside the casing, and an electrolyte. The casing is open at one end along the axial direction, and a cap assembly is disposed at the open end. The core is formed by winding a negative electrode sheet, a separator, and a positive electrode sheet stacked sequentially. The positive electrode sheet is divided into a positive electrode coating area and a positive electrode blank area along its width direction. The positive electrode blank area is flattened to form a positive electrode flattening layer, and the positive electrode flattening layer is connected to the cap assembly through a positive electrode current collector to form a positive end full-tab current collection path. The negative electrode sheet is divided into a negative electrode coating area and a negative electrode blank area along its width direction. The negative electrode blank area is flattened to form a negative electrode flattening layer, and the negative electrode flattening layer is connected to the bottom surface of the unopened end of the casing through a negative electrode current collector to form a negative end full-tab current collection path. The width W of the positive electrode coating area is... p The width W of the negative electrode coating region n Satisfies: 1.008≤W n / W p ≤1.045, W p With W n The unit is mm; the equivalent impedance R of the positive terminal omnipolar collecting path is... top The equivalent impedance R of the current collection path of the negative terminal omnipolar tab bot Satisfy: ΔR end =|R top -R bot |<0.35mΩ, R top With R bot The unit is mΩ.

[0011] This application identifies the equivalent impedance of the positive and negative end current collector paths, and controls the difference between them to be less than 0.35 mΩ. Combined with controlling the ratio of the width of the positive electrode coating area to the width of the negative electrode coating area, this effectively improves the axial thermal uniformity of the all-tab cylindrical lithium-ion battery, reduces the risk of local hot spots and end thermal aging, and enhances the safety performance of the all-tab cylindrical lithium-ion battery.

[0012] In some embodiments of this application, the temperature rise ΔT at the midpoint of the all-tab cylindrical lithium-ion battery at 1 / 2H along the height direction is defined as H. mid The temperature rise at the top of the cap assembly within a range of 5mm to 15mm is ΔT. top The temperature rise at the bottom within a range of 5mm to 15mm from the bottom surface of the casing is ΔT. bot ; Axial temperature difference ΔT of a full-tab cylindrical lithium-ion battery axial =max(ΔT top ,ΔT mid,ΔT bot )-min(ΔT top ,ΔT mid ,ΔT bot Average temperature rise ΔT avg =(ΔT top +ΔT mid +ΔT bot ) / 3, temperature rise uniformity coefficient K Tu =ΔT axial / ΔT avg ΔT top ΔT mid and ΔT bot The unit is ℃; at 25℃ and 100% SOC, under constant current discharge at an 8C rate, the voltage drops to 2.5V or max(ΔT) top ,ΔT mid ,ΔT bot The cutoff temperature is 80℃. The fully tabbed cylindrical lithium-ion battery satisfies: ΔT axial ≤4.5℃, K Tu ≤0.13.

[0013] In this application, SOC represents the instantaneous state of charge of the all-tab cylindrical lithium-ion battery, and SOC = instantaneous capacity of the all-tab cylindrical lithium-ion battery / nominal capacity of the all-tab cylindrical lithium-ion battery × 100%.

[0014] In some embodiments of this application, under conditions of 25°C, 100% SOC, constant current discharge at a rate of 10C is performed until the voltage drops to 2.5V or max(ΔT). top ,ΔT mid ,ΔT bot The cutoff temperature is 80℃. The fully tabbed cylindrical lithium-ion battery satisfies: ΔT axial ≤6.5℃, K Tu ≤0.16.

[0015] In some embodiments of this application, under conditions of 25°C, 100% SOC, constant current discharge at a rate of 12C is performed until the voltage drops to 2.5V or max(ΔT). top ,ΔT mid ,ΔT bot The cutoff temperature is 80℃. The fully tabbed cylindrical lithium-ion battery satisfies: ΔT axial ≤9℃, K Tu ≤0.20.

[0016] In some embodiments of this application, the casing height H and diameter D of the all-tab cylindrical lithium-ion battery satisfy the following conditions: 64.7mm≤H≤65.5mm, 20.8mm≤D≤21.2mm, 3.06≤H / D≤3.14; the discharge capacity of the all-tab cylindrical lithium-ion battery at a 0.2C rate is 4.9Ah~5.2Ah.

[0017] In some embodiments of this application, the width W of the positive electrode coating region p The diameter is 54.4mm to 55.8mm.

[0018] In some embodiments of this application, the width W of the negative electrode coating region n The diameter is 55.4mm to 57.0mm.

[0019] In some embodiments of this application, the width W of the positive electrode coating region p The width W of the negative electrode coating region n Satisfies: 1.011≤W n / W p ≤1.033.

[0020] In some embodiments of this application, the width W of the positive electrode blanking region pe The thickness ranges from 3.0mm to 5.2mm.

[0021] In some embodiments of this application, the width W of the negative electrode blanking area ne The thickness ranges from 2.5mm to 4.8mm.

[0022] In some embodiments of this application, the thickness h of the positive electrode leveling layer p The thickness is 0.08mm to 0.18mm.

[0023] In some embodiments of this application, the thickness h of the negative electrode leveling layer n The thickness is 0.08mm to 0.18mm.

[0024] In some embodiments of this application, the effective contact area A between the positive electrode leveling layer and the positive electrode current collector is... pc 80mm 2 ~120mm 2 .

[0025] In some embodiments of this application, the effective contact area A between the negative electrode leveling layer and the negative electrode current collector is... nc 80mm 2 ~125mm 2 .

[0026] The effective contact area between the positive electrode leveling layer and the positive electrode current collector mentioned in this application refers to the projected area of ​​the overlapping region of the positive electrode leveling layer and the positive electrode current collector, which form a continuous conductive connection after welding, in a plane parallel to the surface of the current collector; the effective contact area between the negative electrode leveling layer and the negative electrode current collector is defined in the same way.

[0027] In some embodiments of this application, the equivalent impedance R of the positive terminal omnipolar current collector path is... top The equivalent impedance R of the current collection path of the negative terminal omnipolar tab bot Satisfies: 0.08mΩ < ΔR end =|R top-Rbot |<0.25mΩ, R top With R bot The unit is mΩ.

[0028] In some embodiments of this application, the DC internal resistance (DCR) of the all-tab cylindrical lithium-ion battery under 8C pulse discharge for 10 seconds at 25°C and 50% SOC is... 50 The resistance is 6.0mΩ to 9.0mΩ.

[0029] In some embodiments of this application, the positive electrode active material of the positive electrode includes LiNi. x Mn y A z O2, 0.88≤x≤0.93, 0<y≤0.12, 0≤z≤0.12, A includes Co and / or Al.

[0030] In some embodiments of this application, the negative electrode active material of the negative electrode sheet includes graphite and / or silicon carbon.

[0031] In some embodiments of this application, the electrolyte includes a lithium salt, a carbonate solvent, and a film-forming additive. The lithium salt includes any one or a combination of at least two of LiPF6, LiFSI, or LiDFOB, and the film-forming additive includes any one or a combination of at least two of VC, FEC, PS, DTD, or LiPO2F2.

[0032] Secondly, this application provides a battery module comprising a full-tab cylindrical lithium-ion battery as described in the first aspect.

[0033] Thirdly, this application provides an electrical device that includes a full-tab cylindrical lithium-ion battery as described in the first aspect, or a battery module as described in the second aspect.

[0034] Compared with the prior art, this application has the following advantages: This application identifies the equivalent impedance of the positive and negative end current collector paths, reduces the difference between them, and, in conjunction with adjusting the ratio of the width of the positive coating area to the width of the negative coating area, effectively improves the axial thermal uniformity of the all-tab cylindrical lithium-ion battery, reduces the risk of local hot spots and end thermal aging, and enhances the safety performance of the all-tab cylindrical lithium-ion battery. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the structure of the all-tab cylindrical lithium-ion battery provided in Example 1.

[0036] Figure 2 This is a schematic diagram of the positive electrode structure of the all-tab cylindrical lithium-ion battery provided in Example 1.

[0037] Figure 3 This is a schematic diagram of the negative electrode structure of the all-tab cylindrical lithium-ion battery provided in Example 1.

[0038] Among them, 10-full-tab cylindrical lithium-ion battery; 11-casing; 12-core; 121-negative electrode sheet; 1211-negative electrode coating area; 1212-negative electrode blank area; 1213-negative electrode flattening layer; 1214-negative electrode copper-plated nickel current collector; 1215-negative electrode winding start end; 1216-negative electrode winding end; 122-positive electrode sheet; 1221-positive electrode coating area; 1222-positive electrode blank area; 1223-positive electrode flattening layer; 1224-positive electrode aluminum current collector; 1225-positive electrode winding start end; 1226-positive electrode winding end; 1227-insulating coating area; 13-cap assembly. Detailed Implementation

[0039] The technical solution of this application will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely to help understand this application and should not be regarded as specific limitations on this application.

[0040] The scope of this application can be defined by lower and upper limits. The selected lower and upper limits define the boundaries of a specific range. The range defined in this way can be defined by the inclusion or exclusion of endpoints. Any endpoint can be independently selected for inclusion or exclusion, and all lower and upper limits can be arbitrarily combined to form new ranges. That is, any lower limit can be combined with any upper limit to form a valid range. For example, if the ranges of 60~120 and 80~110 are listed for specific parameters, it should be understood that the ranges of 60~110 and 80~120 also fall within the scope of this application. In addition, if the minimum range values ​​1 and 2 are listed, and the maximum range values ​​3, 4 and 5 are also listed, then all ranges of 1~3, 1~4, 1~5, 2~3, 2~4 and 2~5 fall within the scope of this application. In this application, the numerical range "a~b" represents a shortened representation of any combination of real numbers between a and b, where a and b are both real numbers. For example, the numerical range "0~5" means that all real numbers between 0 and 5 have been fully listed in this document, and "0~5" is only a shortened representation of this set of numerical combinations. When a parameter is expressed as an integer ≥2, it is equivalent to listing positive integers that meet the requirements, such as 2, 3, 4, 5, 6, 7, 8, 9, 10, etc. When a parameter is expressed as an integer selected from "2~10", it is equivalent to listing any integer among 2, 3, 4, 5, 6, 7, 8, 9, and 10.

[0041] In this application, "at least two combinations" refers to a quantity greater than or equal to 2 unless otherwise specified. For example, "any one or at least two combinations" means any one of the listed items, or a combination of at least two of the listed items formed in a manner that does not conflict and enables the implementation of this application. In this application, unless otherwise specified, the features or solutions corresponding to "and / or" cover any one of two or more related listed items, as well as any and all combinations of the related listed items. The arbitrary and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. For example, "A and / or B" represents a set consisting of A, B, and combinations of A and B, where "containing A and / or B" can be understood, depending on the context of the statement, as containing A, containing B, or simultaneously containing both A and B. In this application, "optional" means that the corresponding feature, component, step or solution is not necessary, that is, it is selected from either "with" or "without". If there are multiple "optional" limitations in a technical solution, unless otherwise specified and there is no technical conflict or mutual constraint, each "optional" limitation is independent and does not affect the others.

[0042] In this application, technical features or solutions described using open-ended terms such as "comprising" or "including" do not exclude additional non-conflicting elements beyond those listed unless otherwise specified. They are considered to disclose both closed-ended features or solutions consisting solely of the listed elements and open-ended features or solutions that may include additional non-conflicting elements beyond the listed elements. For example, if A includes a1, a2, and a3, unless otherwise specified, this means that A can consist only of a1, a2, and a3, or it can include other non-conflicting elements based on a1, a2, and a3. This corresponds to the disclosure of technical solutions such as "A consists of a1, a2, and a3," "A is selected from a1, a2, and a3," and "A not only includes a1, a2, and a3, but may also include other non-conflicting elements." All embodiments and optional embodiments of this application, unless otherwise specified and without technical conflict, can be combined to form new technical solutions, and such combinations fall within the scope of this application. The term "embodiment" as used in this application means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment or implementation of this application. The appearance of this phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art can explicitly and implicitly understand that the embodiments described in this application can be combined with other embodiments that do not conflict with existing technologies. The ordinal numbers "first," "second," "third," and "fourth," etc., used in this application in the expressions "first aspect," "second aspect," "third aspect," and "fourth aspect," are for descriptive purposes only and should not be construed as indicating or implying relative importance or quantity, nor should they be construed as implicitly specifying the importance or quantity of the indicated technical features. They serve only as a non-exhaustive enumeration and do not constitute a closed limitation on quantity.

[0043] In this application, the order in which the steps are written in the methods described in the various embodiments does not imply a strict execution order. The actual execution order of each step should be determined according to its function and possible internal logic. Unless otherwise specified, all steps in this application can be executed in the order they are written, or in any order without technical conflict. For example, if the method includes steps (a) and (b), it means that the method may include steps (a) and (b) executed sequentially, or it may include steps (b) and (a) executed sequentially. If the method also includes step (c), then step (c) can be added to the method in any order without conflict, including but not limited to the execution order of steps (a), (b), and (c), steps (a), (c), and (b), steps (c), (a), and (b), etc.

[0044] In one specific embodiment, this application provides a full-tab cylindrical lithium-ion battery, comprising a casing, a core disposed inside the casing, and an electrolyte. The casing is open at one end along the axial direction, and a cap assembly is disposed at the open end. The core is formed by winding a negative electrode sheet, a separator, and a positive electrode sheet stacked sequentially. The positive electrode sheet is divided into a positive electrode coating area and a positive electrode blank area along its width direction. The positive electrode blank area is flattened to form a positive electrode flattening layer, which is connected to the cap assembly via a positive electrode current collector to form a positive end full-tab current collection path. The negative electrode sheet is divided into a negative electrode coating area and a negative electrode blank area along its width direction. The negative electrode blank area is flattened to form a negative electrode flattening layer, which is connected to the bottom surface of the unopened end of the casing via a negative electrode current collector to form a negative end full-tab current collection path. The width W of the positive electrode coating area is... p The width W of the negative electrode coating region n Satisfies: 1.008≤W n / W p ≤1.045, W p With W n The unit is mm; the equivalent impedance R of the positive terminal omnipolar collecting path is... top The equivalent impedance R of the current collection path of the negative terminal omnipolar tab bot Satisfy: ΔR end =|R top -R bot |<0.35mΩ, R top With R bot The unit is mΩ.

[0045] This application adjusts the width W of the positive electrode coating region. p Width W of the negative electrode coating area n Satisfies: 1.008≤W n / W p ≤1.045, for example, can be 1.008, 1.010, 1.015, 1.020, 1.025, 1.030, 1.035, 1.040 or 1.045, to ensure that the positive electrode region and the negative electrode region form a relatively balanced reaction width and coating relationship within the shell.

[0046] This application modulates the equivalent impedance R of the current collection path at the positive end of the omnipolar junction. top The equivalent impedance R of the current collection path of the negative terminal omnipolar tab bot Satisfy: ΔR end =|R top -R bot| <0.35mΩ, for example, it can be 0.05mΩ, 0.10mΩ, 0.15mΩ, 0.20mΩ, 0.25mΩ, 0.30mΩ or 0.35mΩ. The positive and negative current collection paths form a smaller impedance difference, reducing axial heat generation and thus improving the axial thermal uniformity of the cylindrical cell, reducing the risk of local hot spots and end thermal aging.

[0047] In this application, the equivalent impedance R of the positive end omnidirectional current collector path is controlled by adjusting the welding energy of the positive and negative end omnidirectional current collector paths. top The equivalent impedance R of the current collection path of the negative terminal omnipolar tab bot To satisfy ΔR end <0.35mΩ.

[0048] This application identifies the equivalent impedance of the positive and negative end current collector paths, and controls the difference between them to be less than 0.35 mΩ. Combined with adjusting the ratio of the width of the positive electrode coating area to the width of the negative electrode coating area, this effectively improves the axial thermal uniformity of the all-tab cylindrical lithium-ion battery, reduces the risk of local hot spots and end thermal aging, and enhances the safety performance of the all-tab cylindrical lithium-ion battery.

[0049] In this application, the materials of the positive current collector and the negative current collector are not particularly limited. For example, the positive current collector includes an aluminum current collector, and the negative current collector includes a copper-plated nickel current collector.

[0050] In some embodiments, the temperature rise ΔT at the midpoint of the all-tab cylindrical lithium-ion battery at 1 / 2H along the height direction is defined as H. mid The temperature rise at the top of the cap assembly within a range of 5mm to 15mm is ΔT. top The temperature rise at the bottom within a range of 5mm to 15mm from the bottom surface of the casing is ΔT. bot ; Axial temperature difference ΔT of a full-tab cylindrical lithium-ion battery axial =max(ΔT top ,ΔT mid ,ΔT bot )-min(ΔT top ,ΔT mid ,ΔT bot Average temperature rise ΔT avg =(ΔT top +ΔT mid +ΔT bot ) / 3, temperature rise uniformity coefficient K Tu =ΔT axial / ΔT avg ΔTtop ΔT mid and ΔT bot The unit is ℃; at 25℃ and 100% SOC, under constant current discharge at an 8C rate, the voltage drops to 2.5V or max(ΔT) top ,ΔT mid ,ΔT bot The cutoff temperature is 80℃. The fully tabbed cylindrical lithium-ion battery satisfies: ΔT axial ≤4.5℃, for example, it can be 0.5℃, 1.0℃, 1.5℃, 2.0℃, 2.5℃, 3.0℃, 3.5℃, 4.0℃, or 4.5℃, K Tu ≤0.13, for example, can be 0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.11, 0.12 or 0.13.

[0051] In this application, the top of the all-tab cylindrical lithium-ion battery is defined as a distance of 5mm to 15mm from the top of the cap assembly, for example, 5mm, 7mm, 9mm, 11mm, 13mm or 15mm; the bottom of the all-tab cylindrical lithium-ion battery is defined as a distance of 5mm to 15mm from the bottom surface of the casing, for example, 5mm, 7mm, 9mm, 11mm, 13mm or 15mm.

[0052] In some implementations, under conditions of 25°C and 100% SOC, a constant current discharge at a rate of 10C is performed until the voltage drops to 2.5V or max(ΔT). top ,ΔT mid ,ΔT bot The cutoff temperature is 80℃. The fully tabbed cylindrical lithium-ion battery satisfies: ΔT axial ≤6.5℃, for example, it can be 0.5℃, 1℃, 2℃, 3℃, 4℃, 5℃, 6℃ or 6.5℃, K Tu ≤0.16, for example, it can be 0.02, 0.04, 0.06, 0.08, 0.1, 0.12, 0.14 or 0.16.

[0053] In some implementations, under conditions of 25°C and 100% SOC, a constant current discharge at a rate of 12C is performed until the voltage drops to 2.5V or max(ΔT). top ,ΔT mid ,ΔT bot The cutoff temperature is 80℃. The fully tabbed cylindrical lithium-ion battery satisfies: ΔT axial ≤9℃, for example, can be 1℃, 2℃, 3℃, 4℃, 5℃, 6℃, 7℃, 8℃ or 9℃, K Tu≤0.20, for example, can be 0.05, 0.07, 0.09, 0.10, 0.12, 0.15, 0.17, 0.18 or 0.20.

[0054] In some embodiments, the casing height H and diameter D of the all-tab cylindrical lithium-ion battery satisfy the following conditions: 64.7mm ≤ H ≤ 65.5mm, for example, 64.7mm, 64.8mm, 64.9mm, 65.0mm, 65.1mm, 65.2mm, 65.3mm, 65.4mm, or 65.5mm; and 20.8mm ≤ D ≤ 21.2mm, for example, 20.8mm, 20.9mm, 21.0mm, or 21.2mm. The diameter is 1.1 mm or 21.2 mm, and 3.06 ≤ H / D ≤ 3.14, for example, it can be 3.06, 3.07, 3.08, 3.09, 3.1, 3.11, 3.12, 3.13, or 3.14; the discharge capacity of the all-tab cylindrical lithium-ion battery at a 0.2C rate is 4.9 Ah to 5.2 Ah, for example, it can be 4.9 Ah, 4.95 Ah, 5 Ah, 5.05 Ah, 5.1 Ah, 5.15 Ah, or 5.2 Ah. In this application, the diameter D of the all-tab cylindrical lithium-ion battery refers to the outer diameter of the all-tab cylindrical lithium-ion battery casing.

[0055] In some embodiments, the width W of the positive electrode coating region p The diameter is 54.4mm to 55.8mm, for example, it can be 54.4mm, 54.6mm, 54.8mm, 55mm, 55.2mm, 55.4mm, 55.6mm or 55.8mm.

[0056] In some embodiments, the width W of the negative electrode coating region n The diameter is 55.4mm to 57.0mm, for example, it can be 55.4mm, 55.6mm, 55.8mm, 56mm, 56.2mm, 56.4mm, 56.6mm, 56.8mm or 57.0mm.

[0057] In some embodiments, the width W of the positive electrode coating region p The width W of the negative electrode coating region n Satisfies: 1.011≤W n / W p ≤1.033, for example, it can be 1.011, 1.012, 1.015, 1.018, 1.02, 1.022, 1.025, 1.028, 1.03, 1.032 or 1.033.

[0058] In some implementations, the width W of the positive electrode blanking region peThe thickness ranges from 3.0mm to 5.2mm, for example, it can be 3mm, 3.2mm, 3.5mm, 3.8mm, 4mm, 4.2mm, 4.5mm, 4.8mm, 5mm or 5.2mm.

[0059] In some embodiments, the width W of the negative electrode blanking area ne The thickness ranges from 2.5mm to 4.8mm, for example, it can be 2.5mm, 2.8mm, 3mm, 3.2mm, 3.5mm, 3.8mm, 4mm, 4.2mm, 4.5mm or 4.8mm.

[0060] In some embodiments, the thickness h of the positive electrode leveling layer p The thickness is 0.08mm to 0.18mm, for example, it can be 0.08mm, 0.1mm, 0.12mm, 0.14mm, 0.16mm or 0.18mm.

[0061] In some embodiments, the thickness h of the negative electrode flattening layer n The thickness is 0.08mm to 0.18mm, for example, it can be 0.08mm, 0.1mm, 0.12mm, 0.14mm, 0.16mm or 0.18mm.

[0062] In this application, the thickness of the positive electrode leveling layer and the negative electrode leveling layer is adjusted by adjusting the leveling pressure.

[0063] In some embodiments, the effective contact area A between the positive electrode leveling layer and the positive electrode current collector is... pc 80mm 2 ~120mm 2 For example, it could be 80mm 2 85mm 2 90mm 2 95mm 2 100mm 2 105mm 2 110mm 2 115mm 2 Or 120mm 2 .

[0064] In some embodiments, the effective contact area A between the negative electrode leveling layer and the negative electrode current collector is... nc 80mm 2 ~125mm 2 For example, it could be 80mm 2 85mm 2 90mm 2 95mm 2 100mm 2 105mm 2110mm 2 115mm 2 120mm 2 Or 125mm 2 .

[0065] In some implementations, the equivalent impedance R of the positive terminal omnipolar collector path is... top The equivalent impedance R of the current collection path of the negative terminal omnipolar tab bot Satisfies: 0.08mΩ < ΔR end =|R top-Rbot | < 0.25mΩ, for example, it could be 0.08mΩ, 0.1mΩ, 0.12mΩ, 0.15mΩ, 0.18mΩ, 0.2mΩ, 0.22mΩ, or 0.25mΩ, R top With R bot The unit is mΩ.

[0066] In some embodiments, the all-tab cylindrical lithium-ion battery, at 25°C and 50% SOC, undergoes an 8C rate pulse discharge for 10 seconds, resulting in a DC internal resistance (DCR). 50 The resistance is 6.0mΩ to 9.0mΩ, for example, it can be 6.0mΩ, 6.5mΩ, 7.0mΩ, 7.5mΩ, 8.0mΩ, 8.5mΩ or 9.0mΩ.

[0067] In some embodiments, the positive electrode active material of the positive electrode includes LiNi. x Mn y A z O2, 0.88≤x≤0.93, for example, can be 0.88, 0.89, 0.90, 0.91, 0.92 or 0.93, 0<y≤0.12, for example, can be 0.01, 0.01, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.11 or 0.12, 0≤z≤0.12, for example, can be 0, 0.01, 0.01, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.10, 0.11 or 0.12, A includes Co and / or Al.

[0068] In some embodiments, the negative electrode active material of the negative electrode sheet includes graphite and / or silicon carbon.

[0069] In this application, the positive electrode coating region of the positive electrode sheet and the negative electrode coating region of the negative electrode sheet, in addition to the positive electrode active material and the negative electrode active material, each independently include a binder and a conductive agent. The binder includes any one or a combination of at least two of polyvinylidene fluoride (PVDF), sodium carboxymethyl cellulose (CMC), polyacrylic acid (PAA), or styrene-butadiene rubber (SBR). The conductive agent includes any one or a combination of at least two of conductive carbon black, carbon nanotubes, or graphene.

[0070] In some embodiments, the electrolyte comprises a lithium salt, a carbonate solvent, and a film-forming additive. The lithium salt comprises any one or a combination of at least two of lithium hexafluorophosphate (LiPF6), lithium bis(fluorosulfonylimide) (LiFSI), or lithium difluorooxalate borate (LiDFOB). The film-forming additive comprises any one or a combination of at least two of vinylene carbonate (VC), fluoroethylene carbonate (FEC), 1,3-propanesulfonyl lactone (PS), ethylene sulfate (DTD), or lithium difluorophosphate (LiPO2F2).

[0071] The material of the diaphragm in this application is not particularly limited. For example, the base membrane of the diaphragm includes a polypropylene membrane prepared by dry method or a polyethylene membrane prepared by wet method. At least one side surface of the base membrane is provided with a mixed coating prepared by inorganic ceramics and / or binders. The inorganic ceramics include boehmite, alumina, silicon dioxide, zirconium oxide, barium titanate or magnesium oxide. The binder includes polyvinylidene fluoride and / or polyvinylidene fluoride-hexafluoropropylene copolymer. The total thickness of the diaphragm is 10 μm to 12 μm.

[0072] In another specific embodiment, this application provides a battery module comprising a full-tab cylindrical lithium-ion battery as described in the first aspect.

[0073] In another specific embodiment, this application provides an electrical device that includes a multi-tab cylindrical lithium-ion battery as described in one of the preceding specific embodiments, or a battery module as described in another of the preceding specific embodiments.

[0074] The numerical range described in this application includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this application will not exhaustively list the specific point values ​​included in the range.

[0075] This application also provides a reverse identification method for determining whether any all-tab cylindrical lithium-ion battery is the all-tab cylindrical lithium-ion battery provided in this application. The identification method includes: (1) Measure the cell dimensions H and D, and perform a 0.2C capacity test at 25℃ to confirm whether it meets the requirements of 64.7mm≤H≤65.5mm, 20.8mm≤D≤21.2mm, 3.06≤H / D≤3.14, and is a full-tab cylindrical lithium-ion battery with a capacity of 4.9Ah~5.2Ah. (2) Three cells with stable capacity were selected and charged to 100% SOC. After standing in a 25℃ environment for 2 hours, discharge tests were conducted at 8C, 10C and 12C rates, respectively. Before the test, thermocouples were attached at 5mm~15mm from the positive terminal, at 1 / 2H of the axial height and 5mm~15mm from the negative terminal. The sampling frequency was 1Hz. The highest temperature at the three temperature measurement points was recorded and the ambient temperature was subtracted to obtain ΔT. top ΔT mid and ΔT bot Simultaneous calibration using a thermal imager. ΔT was calculated based on the test results. axial ΔT avg and K Tu Whether all of them are within the scope of this application. (3) Adjust the cells of the same batch to 50% SOC, let them stand at 25℃±2℃ for 2 hours, apply a 10s, 8C current discharge pulse, and record the voltage U0 before the pulse and the voltage U at the 10s mark of the pulse. 10 DCR 50 =(U0-U 10 ) / I, where I is the 8C pulse discharge current, confirming DCR 50 Whether it falls within the scope of this application.

[0076] (4) Disassemble the battery cell under safe conditions, separate the positive terminal current collection path and the negative terminal current collection path, and measure R using a four-terminal micro-ohmmeter. top and R bot Calculate ΔR end Whether it falls within the scope of this application; then unfold the positive and negative electrode sheets, measure the width of the material area at the beginning, middle and end of the roll respectively, and calculate W. p W n and W n / W p Simultaneously, the thickness h of the positive electrode leveling layer was measured. p The thickness h of the negative electrode flattening layer n The effective contact area of ​​the manifold was calculated by combining CT and cross-sectional microscopic images to determine W. n / W p The thickness of the leveling layer and whether the effective contact area between the leveling layer and the manifold falls within the scope of this application.

[0077] If the battery cell under test simultaneously meets W n / W pWith ΔR end Core parameters, including H, D, and C. 0.2 If the cell falls within the scope of this application, it can be determined that the cell under test has the axial temperature rise uniformity and material area width matching relationship described in this application.

[0078] To clearly illustrate the technical solution of this application, the parameter testing method of the all-tab cylindrical lithium-ion battery and the preparation method of the positive and negative electrode sheets are described below.

[0079] Parameter testing methods: (1) Test method for the casing height H and diameter D of a cylindrical lithium-ion battery with all tabs: The cell was left to stand in an environment of 25℃±2℃ for 2 hours to remove contaminants from the outer surface, but the outer sheath was retained. Using a height gauge with a resolution of not less than 0.01mm, the total height of the cylindrical casing was measured at three positions approximately 120° apart on the circumference of the cell, and the average of the three measurements was taken as the height H. Using an outside micrometer with a resolution of not less than 0.01mm, the diameter was measured once in each of two mutually perpendicular directions at the axial center of the cell, and the average of the two measurements was taken as the diameter D.

[0080] (2) Width W of the positive electrode coating area p Width W of the negative electrode coating area n The testing method is as follows: After discharging the battery cell to 2.5V, disassemble it in a dry environment, remove the core, and unfold the positive and negative electrode plates. A two-dimensional image measuring instrument with a resolution of at least 0.01mm is used to measure the width of the positive and negative electrode coating areas. Specifically, one position is selected at each of the beginning, middle, and end of each positive or negative electrode plate along its length. Three points are measured at each position along the width direction of the coating area. The average of the nine measurements is recorded as W. p The average of the nine measurements at the negative electrode is denoted as W. n .

[0081] (3) Thickness h of the positive electrode leveling layer p The thickness h of the negative electrode flattening layer n Test method: The all-tab cylindrical lithium-ion battery was disassembled, and the positive and negative electrode leveling layers were then resin-embedded and their cross-sections polished, respectively. Using an optical microscope, the thickness of the leveling layer was measured at six uniformly selected locations along the circumference of each end face. The average of the six measurements for the positive electrode leveling layer was recorded as h. p The average of the six measurements of the negative electrode leveling layer is recorded as h. n .

[0082] (4) Effective contact area A between the positive electrode leveling layer and the positive electrode current collector pc The effective contact area A between the negative electrode leveling layer and the negative electrode current collector ncTest method: The all-tab cylindrical lithium-ion battery was disassembled, and the positive current collector and positive flattened layer, and the negative current collector and negative flattened layer were separated separately. The contact indentation area between the current collector and the flattened layer was photographed using an optical microscope. The effective contact area was identified using image analysis software according to a uniform grayscale threshold. The area of ​​the effective contact area of ​​the positive current collector was recorded as A. pc The effective contact area of ​​the negative electrode current collector is denoted as A. nc Each sample should be measured at least three fields of view and the total effective contact area should be calculated.

[0083] (5) DCR 50 Test method: Adjust the state of charge (SOC) of the all-tab cylindrical lithium-ion battery to 50%, let it stand at 25℃±2℃ for 2 hours, apply a 10s, 8C current discharge pulse, and record the voltage U0 before the pulse and the voltage U at the 10s mark of the pulse. 10 DCR 50 =(U0-U 10 ) / I, where I is the 8C pulse discharge current. Based on the nominal capacity of a full-tab cylindrical lithium-ion battery of 5A, the 8C current = 8 × 5 = 40A.

[0084] (6) Test method for discharge capacity of all-tab cylindrical lithium-ion battery at 0.2C rate: Take a cell with stable capacity after at least 2 formation and capacity testing, charge it to the nominal capacity, i.e. 100% SOC, at 25℃±2℃ according to the standard charging regime, let it stand for 30 minutes, and then discharge it to 2.5V at a constant current of 0.2C rate. Record the discharge capacity at 0.2C rate in Ah.

[0085] (7) Equivalent impedance R of the positive terminal omnipolar collecting path top The equivalent impedance R of the current collection path of the negative terminal omnipolar tab bot Test method: The cylindrical lithium-ion battery with all tabs was discharged to 2.5V and disassembled in a dry environment with a dew point not higher than -40℃. The positive terminal flattened layer-positive current collector-cap assembly was separated as the positive terminal all tab current collector path, and the negative terminal flattened layer-negative current collector-bottom of the casing was separated as the negative terminal all tab current collector path. The equivalent impedance R of the positive terminal all tab current collector path was measured using a four-terminal micro-ohmmeter. top The equivalent impedance R of the current collection path of the negative terminal omnipolar tab bot The test current is 500mA, the test frequency is 1kHz, and each test piece is tested 5 times and the average value is taken.

[0086] (8)ΔT top ΔT mid and ΔT botTest method: Charge the all-tab cylindrical lithium-ion battery to 100% SOC and let it stand for 2 hours in an environment of 25℃±2℃. Place a top thermocouple on the side wall of the casing within a range of 5mm~15mm from the end face of the positive electrode cap assembly, a middle thermocouple on the side wall of the casing at 1 / 2H of the cell's axial height, and a bottom thermocouple on the side wall of the casing within a range of 5mm~15mm from the bottom surface of the casing. All three thermocouples are K-type patch thermocouples with a sampling frequency of 1Hz. Simultaneously, a thermal imager is placed 0.6m to 0.8m from the cell side wall to verify the highest temperature and hot spot location of the thermocouples. When the deviation between the thermal imager and the thermocouple readings exceeds 1.5℃, the thermocouples are reattached and the test is repeated. Before testing, the thermal imager is calibrated at two points using a blackbody source at temperatures of 30℃ and 70℃, with an emissivity set to 0.95.

[0087] From the same batch of all-tab cylindrical lithium-ion batteries, three batteries with stable capacity were selected and discharged at constant current rates of 8C, 10C, and 12C to 2.5V or max(ΔT). top ,ΔT mid ,ΔT bot The system safely shuts off at 80℃. Record the highest temperatures at the three temperature measurement points and subtract the ambient temperature to obtain ΔT. top ΔT mid and ΔT bot .

[0088] In the embodiments and comparative examples of this application, the preparation method of the positive electrode includes: LiNi 0.9 Co 0.05 Mn 0.05 O2, conductive carbon black, carbon nanotubes, and PVDF were mixed in a mass ratio of 97.25:1.40:0.20:1.15, and NMP was used as a solvent to prepare a positive electrode slurry. The positive electrode slurry was intermittently coated on both sides of an aluminum foil with a thickness of 12 μm to sequentially form adjacent positive electrode coating areas and positive electrode blank areas; after drying, rolling, and slitting, the positive electrode sheet was obtained.

[0089] In the embodiments and comparative examples of this application, the method for preparing the negative electrode sheet includes: Artificial graphite, silicon carbide, conductive carbon black, CMC, and SBR were mixed in a mass ratio of 82.0:14.0:1.0:1.2:1.8, and deionized water was used as a solvent to prepare a negative electrode slurry. The negative electrode slurry was intermittently coated on both sides of a 6μm thick copper foil to sequentially form adjacent negative electrode coating areas and negative electrode blank areas; after drying, rolling, and slitting, the negative electrode sheet was obtained.

[0090] In the embodiments and comparative examples of this application, the electrolyte used contains lithium salt including LiPF6 with a concentration of 1.10 mol / L, solvent including ethylene carbonate (EC), ethyl methyl carbonate (EMC) and diethyl carbonate (DEC) in a volume ratio of 1:1:1, and film-forming additives including VC accounting for 1 wt% of the total mass of the electrolyte and FEC accounting for 2 wt%.

[0091] In the embodiments and comparative examples of this application, the diaphragm used includes a wet-process polyolefin base membrane with a base membrane thickness of 9 μm. One side surface of the base membrane is coated with a coating formed by alumina ceramic particles and PVDF with a coating thickness of 2 μm.

[0092] The above description is only for the purpose of clearly illustrating the technical solution of this application and is not intended to be considered as a further limitation of this application.

[0093] Example 1 This embodiment provides a fully tabbed cylindrical lithium-ion battery, such as... Figures 1 to 3 As shown, the all-tab cylindrical lithium-ion battery 10 includes a housing 11, a core 12 disposed inside the housing 11, and an electrolyte. The housing 11 has a height H of 65.1 mm, a diameter D of 21.0 mm, and an H / D ratio of 3.10. The housing 11 has an opening at one end along the axial direction, and the core 12 is placed in the housing 11 through the opening. A cap assembly 13 is provided at one end of the opening for sealing. The core 12 is formed by winding a negative electrode sheet 121, a separator, and a positive electrode sheet 122 that are stacked in sequence.

[0094] The positive electrode sheet 122 includes a positive electrode winding start end 1225 and a positive electrode winding end end 1226 along its length direction, and is divided into a positive electrode coating area 1221 and a positive electrode blank area 1222 along its width direction. An insulating coating area 1227 with a width of 2 mm is provided at the boundary between the positive electrode coating area and the positive electrode blank area; the width W of the positive electrode coating area 1221 is... p The width W of the positive electrode blank area 1222 is 55.0 mm. pe The thickness is 4.0 mm, and the areal density of the single-sided coating area of ​​the positive electrode 122 is 13.2 mg / cm². 2 The compacted density is 3.55 g / cm³. 3 The positive electrode blank area 1222 is flattened to form a positive electrode flattened layer 1223, the thickness of which is h. p The effective contact area A between the positive electrode leveling layer 1223 and the positive electrode aluminum current collector 1224 is 0.12mm. pc 98mm 2 The positive electrode flattening layer 1223 is connected to the cap assembly 13 via the positive electrode aluminum current collector 1224, forming a positive electrode full-tab current collection path. The equivalent impedance R of the positive electrode full-tab current collection path is... top It is 1.62mΩ.

[0095] The negative electrode sheet 121 includes a negative electrode winding start end 1215 and a negative electrode winding end end 1216 along its length and is divided into a negative electrode coating area 1211 and a negative electrode blank area 1212 along its width; the width W of the negative electrode coating area 1211 is... n The width W of the negative electrode blank area 1212 is 56.0 mm. ne The thickness is 3.5 mm, and the areal density of the single-sided coating area of ​​the negative electrode 121 is 5.8 mg / cm³. 2 The compacted density is 1.58 g / cm³. 3 The negative electrode blank area 1212 is flattened to form a negative electrode flattening layer 1213, the thickness of which is h. n The effective contact area Anc between the negative electrode flattening layer 1213 and the negative electrode copper-plated nickel current collector 1214 is 105 mm², which is 0.12 mm². 2 The negative electrode flattening layer 1213 is connected to the bottom surface of the unopened end of the housing 11 via the negative electrode copper-plated nickel current collector 1214, forming a negative electrode full-tab current collection path. The equivalent impedance R of the negative electrode full-tab current collection path is... bot It is 1.80mΩ.

[0096] The width ratio W of the positive electrode coating region 1221 to the negative electrode coating region 1211 n / W p The equivalent impedance of the current collection path of the positive and negative terminals is 1.018, satisfying: ΔR end =|R top -R bot = 0.18mΩ < 0.35mΩ.

[0097] The fully tabbed cylindrical lithium-ion battery 10 has a discharge capacity of 5.02 Ah at a 0.2C rate.

[0098] Example 2 This embodiment provides a fully tabbed cylindrical lithium-ion battery. The fully tabbed cylindrical lithium-ion battery has a casing height H of 65.3 mm, a diameter D of 20.8 mm, and an H / D ratio of 3.14. The width W of the negative electrode coating area... n With a diameter of 56.8mm, W n / W p The value changes from 1.018 to 1.033. The discharge capacity of the all-tab cylindrical lithium-ion battery at a 0.2C rate is 5.01Ah. The equivalent impedance R of the positive terminal all-tab current collector path is... top The equivalent impedance R of the negative terminal all-hole current collector path is 1.62mΩ. bot It is 1.83mΩ, ΔR end =|R top -R botExcept for |=0.21mΩ<0.35mΩ, everything else is the same as in Example 1.

[0099] Example 3 This embodiment provides a fully tabbed cylindrical lithium-ion battery. The fully tabbed cylindrical lithium-ion battery has a casing height H of 64.7 mm, a diameter D of 21.14 mm, and an H / D ratio of 3.06. The width W of the negative electrode coating area... n With a diameter of 55.6mm, W n / W p The value changes from 1.018 to 1.011. The discharge capacity of the all-tab cylindrical lithium-ion battery at a 0.2C rate is 5.00 Ah. The equivalent impedance R of the positive terminal all-tab current collector path is... top The equivalent impedance R of the negative terminal all-hole current collector path is 1.62mΩ. bot It is 1.84mΩ, ΔR end =|R top -R bot Except for |=0.22mΩ<0.35mΩ, everything else is the same as in Example 1.

[0100] Example 4 This embodiment provides a fully tabbed cylindrical lithium-ion battery, wherein the width W of the positive electrode coating area is... p The width W of the negative electrode coating area is 55.8 mm. n With a diameter of 56.6mm, W n / W p The value changes from 1.018 to 1.014. The discharge capacity of the all-tab cylindrical lithium-ion battery at a 0.2C rate is 5.05Ah. The equivalent impedance R of the positive terminal all-tab current collector path is... top The equivalent impedance R of the negative terminal all-hole current collector path is 1.63mΩ. bot It is 1.83mΩ, ΔR end =|R top -R bot Except for |=0.20mΩ<0.35mΩ, everything else is the same as in Example 1.

[0101] Example 5 This embodiment provides a fully tabbed cylindrical lithium-ion battery, wherein the width W of the positive electrode coating area is... p The width W of the negative electrode coating area is 54.4 mm. n It is 55.4mm, W n / W p Keeping 1.018 constant, the discharge capacity of the all-tab cylindrical lithium-ion battery at a 0.2C rate is 4.96Ah, and the equivalent impedance R of the positive terminal all-tab current collector path is... topThe equivalent impedance R of the negative terminal all-hole current collector path is 1.60mΩ. bot It is 1.80mΩ, ΔR end =|R top -R bot Except for |=0.20mΩ<0.35mΩ, everything else is the same as in Example 1.

[0102] Example 6 This embodiment provides a fully tabbed cylindrical lithium-ion battery, wherein the width W of the positive electrode coating area is... p The width W of the negative electrode coating area is 55.2 mm. n With a diameter of 57.0 mm, W n / W p The value changes from 1.018 to 1.033. The discharge capacity of the all-tab cylindrical lithium-ion battery at a 0.2C rate is 5.03 Ah. The equivalent impedance R of the positive terminal all-tab current collector path is... top The equivalent impedance R of the negative terminal all-hole current collector path is 1.61mΩ. bot It is 1.84mΩ, ΔR end =|R top -R bot Except for |=0.23mΩ<0.35mΩ, everything else is the same as in Example 1.

[0103] Example 7 This embodiment provides a fully tabbed cylindrical lithium-ion battery, wherein the width W of the positive electrode coating area is... p The width W of the negative electrode coating area is 54.8 mm. n With a diameter of 55.4mm, W n / W p The value changes from 1.018 to 1.011. The discharge capacity of the all-tab cylindrical lithium-ion battery at a 0.2C rate is 4.96 Ah. The equivalent impedance R of the positive terminal all-tab current collector path is... top The equivalent impedance R of the negative terminal all-hole current collector path is 1.61mΩ. bot It is 1.85mΩ, ΔR end =|R top -R bot Except for |=0.24mΩ<0.35mΩ, everything else is the same as in Example 1.

[0104] Example 8 This embodiment provides a fully tabbed cylindrical lithium-ion battery. The fully tabbed cylindrical lithium-ion battery, in addition to adjusting the positive terminal welding energy to 92% of that in Embodiment 1 and adjusting the negative terminal welding energy to 104% of that in Embodiment 1, achieves the following: the equivalent impedance R of the positive terminal fully tab current collector path is... topThe equivalent impedance R of the negative terminal total tab current collection path is 1.93mΩ. bot It is 1.63mΩ, ΔR end =|R top -R bot |=0.30mΩ<0.35mΩ, except that the discharge capacity of the all-tab cylindrical lithium-ion battery at 0.2C rate is 5.01Ah, everything else is the same as in Example 1.

[0105] Example 9 This embodiment provides a fully tabbed cylindrical lithium-ion battery. The fully tabbed cylindrical lithium-ion battery, in addition to adjusting the flattening pressure at the positive and negative ends, allows for adjustments to the positive electrode flattening layer thickness h. p The thickness of the negative electrode leveling layer, h, was changed from 0.12mm to 0.16mm. n The equivalent impedance R of the positive terminal full-tab current collector path changes from 0.12mm to 0.15mm. top The equivalent impedance R of the negative terminal all-hole current collector path is 1.90mΩ. bot It is 1.63mΩ, ΔR end =|R top -R bot |=0.27mΩ<0.35mΩ, except that the discharge capacity of the all-tab cylindrical lithium-ion battery at 0.2C rate is 5.00Ah, everything else is the same as in Example 1.

[0106] Example 10 This embodiment provides a fully tabbed cylindrical lithium-ion battery. The fully tabbed cylindrical lithium-ion battery, in addition to adjusting the effective contact area diameter between the positive electrode current collector and the positive electrode leveling layer to 10.4 mm and the effective contact area diameter between the negative electrode current collector and the negative electrode leveling layer to 10.7 mm, allows A... pc From 98mm 2 It becomes 84mm 2 A nc From 105mm 2 Change to 90mm 2 The equivalent impedance R of the positive end omnipolar collector path top The equivalent impedance R of the negative terminal total tab current collection path is 1.93mΩ. bot It is 1.64mΩ, ΔR end =|R top -R bot |=0.29mΩ<0.35mΩ, except that the discharge capacity of the all-tab cylindrical lithium-ion battery at 0.2C rate is 5.00Ah, everything else is the same as in Example 1.

[0107] Example 11 This embodiment provides a fully tabbed cylindrical lithium-ion battery. The fully tabbed cylindrical lithium-ion battery, in addition to adjusting the positive terminal welding energy to 102% of that in Embodiment 1 and adjusting the negative terminal welding energy to 101% of that in Embodiment 1, achieves the following: the equivalent impedance R of the positive terminal fully tab current collector path is... top The equivalent impedance R of the negative terminal all-hole current collector path is 1.66mΩ. bot It is 1.76mΩ, ΔR end =|R top -R bot |=0.10mΩ<0.35mΩ, except that the discharge capacity of the all-tab cylindrical lithium-ion battery at 0.2C rate is 5.02Ah, everything else is the same as in Example 1.

[0108] Example 12 This embodiment provides a fully tabbed cylindrical lithium-ion battery. The fully tabbed cylindrical lithium-ion battery, in addition to adjusting the flattening pressure at the positive and negative ends, allows for adjustments to the positive electrode flattening layer thickness h. p The thickness of the negative electrode leveling layer, h, was changed from 0.12mm to 0.08mm. n The equivalent impedance R of the positive terminal all-hole collector path changes from 0.12mm to 0.09mm. top The equivalent impedance R of the negative terminal all-hole current collector path is 1.84mΩ. bot It is 1.61mΩ, ΔR end =|R top -R bot |=0.23mΩ<0.35mΩ, except that the discharge capacity of the all-tab cylindrical lithium-ion battery at 0.2C rate is 5.01Ah, everything else is the same as in Example 1.

[0109] Example 13 This embodiment provides a fully tabbed cylindrical lithium-ion battery. The fully tabbed cylindrical lithium-ion battery, in addition to adjusting the effective contact area diameter between the positive electrode current collector and the positive electrode flattening layer to 12.2 mm and the effective contact area diameter between the negative electrode current collector and the negative electrode flattening layer to 12.6 mm, allows A... pc From 98mm 2 It becomes 116mm 2 A nc From 105mm 2 It becomes 124mm 2 The equivalent impedance R of the positive end omnipolar collector path top The equivalent impedance R of the negative terminal all-hole current collector path is 1.55mΩ. bot It is 1.70mΩ, ΔR end =|R top -R bot|=0.15mΩ<0.35mΩ, except that the discharge capacity of the all-tab cylindrical lithium-ion battery at 0.2C rate is 5.02Ah, all other conditions are the same as in Example 1.

[0110] Comparative Example 1 This comparative example provides a fully tabbed cylindrical lithium-ion battery, wherein the width W of the negative electrode coating area of ​​the fully tabbed cylindrical lithium-ion battery is [not specified]. n With a diameter of 55.1mm, W n / W p The value changes from 1.018 to 1.002. The discharge capacity of the all-tab cylindrical lithium-ion battery at a 0.2C rate is 4.99 Ah. The equivalent impedance R of the positive terminal all-tab current collector path is... top The equivalent impedance R of the negative terminal all-hole current collector path is 1.62mΩ. bot It is 1.98mΩ, ΔR end =|R top -R bot Except for |=0.36mΩ>0.35mΩ, everything else is the same as in Example 1.

[0111] Comparative Example 2 This comparative example provides a fully tabbed cylindrical lithium-ion battery, wherein the width W of the negative electrode coating area of ​​the fully tabbed cylindrical lithium-ion battery is [not specified]. n With a diameter of 58.0 mm, W n / W p The value changes from 1.018 to 1.055. The discharge capacity of the all-tab cylindrical lithium-ion battery at a 0.2C rate is 5.02 Ah. The equivalent impedance R of the positive terminal all-tab current collector path is... top The equivalent impedance R of the negative terminal all-hole current collector path is 1.60mΩ. bot It is 1.99mΩ, ΔR end =|R top -R bot Except for |=0.39mΩ>0.35mΩ, everything else is the same as in Example 1.

[0112] Comparative Example 3 This comparative example provides a fully tabbed cylindrical lithium-ion battery. The fully tabbed cylindrical lithium-ion battery, in addition to adjusting the positive terminal welding energy to 82% of that in Example 1 and adjusting the negative terminal welding energy to 110% of that in Example 1, achieves the following: the equivalent impedance R of the positive terminal fully tab current collector path is... top The equivalent impedance R of the negative terminal all-hole current collector path is 2.08mΩ. bot It is 1.60mΩ, ΔR end =|R top -R bot|=0.48mΩ>0.35mΩ, except that the discharge capacity of the all-tab cylindrical lithium-ion battery at 0.2C rate is 5.01Ah, everything else is the same as in Example 1.

[0113] Comparative Example 4 This comparative example provides a fully tabbed cylindrical lithium-ion battery. The fully tabbed cylindrical lithium-ion battery, in addition to adjusting the flattening pressure at the positive and negative ends, allows for adjustments to the positive electrode flattening layer thickness h. p The thickness of the negative electrode leveling layer, h, was changed from 0.12mm to 0.24mm. n The equivalent impedance R of the positive terminal full-tab current collector path changes from 0.12mm to 0.23mm. top The equivalent impedance R of the negative terminal total tab current collection path is 2.02mΩ. bot It is 1.58mΩ, ΔR end =|R top -R bot |=0.44mΩ>0.35mΩ, except that the discharge capacity of the all-tab cylindrical lithium-ion battery at 0.2C rate is 5.00Ah, everything else is the same as in Example 1.

[0114] Comparative Example 5 This comparative example provides a fully tabbed cylindrical lithium-ion battery. The fully tabbed cylindrical lithium-ion battery, in addition to adjusting the effective contact area diameter between the positive electrode current collector and the positive electrode leveling layer to 9.6 mm and the effective contact area diameter between the negative electrode current collector and the negative electrode leveling layer to 10.0 mm, allows A... pc From 98mm 2 It becomes 72mm 2 A nc From 105mm 2 It becomes 78mm 2 The equivalent impedance R of the positive end omnipolar collector path top The equivalent impedance R of the negative terminal all-hole current collector path is 2.06mΩ. bot It is 1.60mΩ, ΔR end =|R top -R bot |=0.46mΩ>0.35mΩ, except that the discharge capacity of the all-tab cylindrical lithium-ion battery at 0.2C rate is 4.99Ah, everything else is the same as in Example 1.

[0115] Performance testing: The nominal capacity (0.2C rate discharge capacity) of the all-tab cylindrical lithium-ion battery provided in all the above embodiments and comparative examples, and the equivalent impedance R of the positive terminal all-tab current collector path. top The equivalent impedance R of the negative end total electrode current collector path bot and ΔR end As shown in Table 1.

[0116] All the above-described embodiments and the comparative examples were subjected to 8C pulse discharge for 10 seconds at 25°C and 50% SOC. The voltage before the pulse U0 and the voltage at the 10th second of the pulse were recorded. 10 DCR 50 =(U0-U 10 ) / I, where I is the 8C pulse discharge current, DCR 50 The test results are shown in Table 1.

[0117] Table 1 Three batteries with stable capacity were selected from all the above embodiments and comparative examples of the all-tab cylindrical lithium-ion batteries, charged to 100% SOC, and left to stand for 2 hours in an environment of 25℃±2℃. Then, under the condition of an initial temperature of 25℃, they were discharged at constant current rates of 8C, 10C, and 12C to 2.5V or max(ΔT). top ,ΔT mid ,ΔT bot The system safely shuts off at 80℃. Record the highest temperatures at the three temperature measurement points and subtract the ambient temperature (25℃) to obtain ΔT. top ΔT mid and ΔT bot Calculate the axial temperature difference ΔT of the all-tab cylindrical lithium-ion battery. axial =max(ΔT top ,ΔT mid ,ΔT bot )-min(ΔT top ,ΔT mid ,ΔT bot Average temperature rise ΔT avg =(ΔT top +ΔT mid +ΔT bot ) / 3, temperature rise uniformity coefficient K Tu =ΔT axial / ΔT avg The test results at 8C are shown in Table 2, the test results at 10C are shown in Table 3, and the test results at 12C are shown in Table 4.

[0118] Table 2 Table 3 Table 4 Based on the test results in Tables 1 to 4, the width W of the positive electrode coating region of the all-tab cylindrical lithium-ion batteries provided in Examples 1 to 13 is...p The width W of the negative electrode coating region n All satisfy 1.008≤W n / W p ≤1.045, equivalent impedance R of the positive terminal omnipolar collecting path top The equivalent impedance R of the current collection path of the negative terminal omnipolar tab bot All satisfy: ΔR end =|R top -R bot | <0.35mΩ, the nominal capacity of all-tab cylindrical lithium-ion batteries is within the capacity window of 4.9Ah to 5.2Ah, and the DCR 50 Within the range of 6.0 mΩ to 9.0 mΩ, the discharge ΔT at an 8C rate... axial Not higher than 4.5℃, K Tu Not higher than 0.13, ΔT of discharge at 10C rate. axial Not higher than 6.5℃, K Tu Not higher than 0.16, ΔT of discharge at 12C rate axial Not higher than 9℃, K Tu Not higher than 0.20.

[0119] The cylindrical lithium-ion batteries with full tabs provided in Comparative Examples 1 to 5, although having nominal capacities close to those of the embodiments, exhibit different characteristics due to the width W of the positive electrode coating area. p The width W of the negative electrode coating region n The ratio W n / W p And the equivalent impedance R of the positive terminal omnipolar current collector path. top The equivalent impedance R of the current collection path of the negative terminal omnipolar tab bot The difference ΔR end When the preferred range identified in this application is not simultaneously met, and discharge tests are conducted under the same conditions, the ΔT of the all-tab cylindrical lithium-ion battery is... axial and K Tu The significant increase in all three indicates an increased risk of localized hotspots at the top, middle, and bottom.

[0120] As can be confirmed from the above, this application effectively improves the axial thermal uniformity of the all-tab cylindrical lithium-ion battery by identifying the equivalent impedance of the positive terminal all-tab current collector path and the equivalent impedance of the negative terminal all-tab current collector path, and controls the difference between the equivalent impedance of the positive terminal all-tab current collector path and the equivalent impedance of the negative terminal all-tab current collector path to be less than 0.35mΩ. Combined with controlling the ratio of the width of the positive electrode coating area to the width of the negative electrode coating area, this improves the thermal uniformity of the all-tab cylindrical lithium-ion battery, reduces the risk of local hot spots and end thermal aging, and enhances the safety performance of the all-tab cylindrical lithium-ion battery.

[0121] Specifically, comparing the test results of Examples 1 to 3 with those of Comparative Examples 1 and 2 confirms that the width W of the positive electrode coating region... p The width W of the negative electrode coating region n The ratio W n / W p When the value is in the range of 1.008 to 1.045, the negative electrode region can form an appropriate width of coverage over the positive electrode region, and the current is more evenly distributed in the relative regions of the positive and negative electrodes. n / W p When the voltage is too low, the negative electrode edge coverage is insufficient, the current density per unit width in the positive electrode edge region increases, and local polarization and Joule heating near the end increase. n / W p When the temperature is too high, the width of the negative electrode material area increases excessively, which will encroach on the edge and end assembly allowance of the winding core, causing uneven compression of the winding edge, uneven current collection path at the end, and uneven electrolyte wetting path, resulting in excessively high temperature rise at the top or bottom. Therefore, W n / W p It is not necessarily better to have a larger capacity; rather, it should be kept within a range that can balance capacity, edge coverage, and end thermal uniformity.

[0122] Comparing the test results of Example 1 with those of Examples 4 and 5 confirms that the width W of the positive electrode region... p This affects the current load per unit width and the heat source distribution at the positive electrode. The current load per unit width referred to in this application is the equivalent operating current borne by a unit width of the positive electrode coating under a given discharge current, approximately equal to the discharge current and W. p The ratio of W. p When the range is too narrow, to achieve a capacity window of 4.9Ah to 5.2Ah, it is necessary to increase the areal density of the positive electrode active material or the local reaction load. The positive electrode end region is more prone to forming localized heat sources during high-rate discharge. p When appropriately increased, the current load per unit width can be reduced; however, W p If it is too large, it will compress the effective space for the positive electrode blank area, the positive electrode leveling layer, and the positive electrode current collector, resulting in R top Increase and make the end collector impedance difference ΔR end Rise. Examples 4 and 5 show that W p A balance can be achieved between capacity loading and end-capacity manifold space within the range of 54.4 mm to 55.8 mm.

[0123] Comparing the test results of Examples 1, 6, and 7, it can be confirmed that the width W of the negative electrode material region... n It serves both to absorb the volume and to affect the uniformity of axial temperature rise. W nAt higher values, the negative electrode capacity margin increases, and an excessively large negative electrode coating area increases the stacking thickness at the winding edge, compressing the current collection space at the negative electrode end. However, according to the test results of Example 6, even when the width of the negative electrode coating area is close to the upper limit, a lower K value can still be maintained. Tu This means that as long as ΔR end Within a certain range, increasing the width of the negative electrode coating area can still be implemented; W n At lower levels, insufficient negative electrode coverage and capacity tolerance amplify the non-uniformity of the reaction at the bottom negative electrode; Example 7: Width W of the negative electrode coating area n When approaching the lower limit, K at 8C rate discharge Tu The value is close to the upper limit, indicating that the lower limit of the negative electrode material region width has a constraining effect on the axial thermal uniformity of the short-height 5Ah cell.

[0124] Comparing the test results of Example 1, Example 8, and Comparative Example 3, it can be confirmed that the end current collector impedance difference ΔR end This directly affects the Joule heat distribution at the positive and negative ends. When ΔR end When the temperature is relatively low, the heat sources at the positive and negative ends are close, and the axial temperature profile is mainly determined by the reaction heat in the middle of the core and the heat dissipation from the sidewalls. ΔT axial Lower. When ΔR in Comparative Example 3 is lower. end When the impedance is increased to 0.48 mΩ, the Joule heating at the higher impedance end increases significantly, causing the temperature at the corresponding end to rise rapidly, K. Tu The value exceeds 0.20. Therefore, it can be seen that simply reducing the total DCR cannot guarantee axial thermal uniformity; the impedance difference between the positive and negative current collector paths must be controlled at a low level simultaneously.

[0125] Comparing the test results of Examples 1 and 9 with Comparative Example 4 confirms that the thickness of the flattening layer affects the end foil crimping, current collector bonding, and local conductive cross-section. An excessively thin flattening layer may cause insufficient contact, while an excessively thick layer will lead to end compression and accumulation, resulting in a decrease in the effective local contact area and current detours. In Example 9, h... p and h n Even after increasing to 0.16mm and 0.15mm, the diameter remains within a controllable range, and ΔT remains within the controllable range during 8C discharge. axial The temperature did not exceed 4.5℃; in Comparative Example 4, h p and h n Increasing the thickness to 0.24mm and 0.23mm resulted in an increase in the end current collection impedance difference, leading to enhanced localized heating at the top or bottom. This indicates that the thickness of the leveling layer needs to be matched with the width of the material zone and the contact area of ​​the collecting disc.

[0126] Comparing the test results of Examples 1 and 10 with Comparative Example 5 confirms that the effective contact area of ​​the current collector determines the uniformity of current entering the external terminals from the tab end face. When the contact area is appropriately reduced, but within the required range, and the end current collection path can still maintain a low impedance difference, the axial thermal uniformity of the tab cylindrical lithium-ion battery can still be maintained within a controllable range, ΔT. axial and K Tu Smaller; but when compared to A in Example 5 pc and A nc Reduced to 72mm respectively 2 and 78mm 2 At this time, the current density carried by the local contact point increases, and the Joule heating near the welding area increases significantly, resulting in ΔT axial and K Tu The temperature rise is significantly higher. This result indicates that the uniformity of axial temperature rise in a multi-tab cell depends not only on the electrode body but also on the actual contact area between the flattened end face and the current collector.

[0127] The applicant declares that the above description is only a specific implementation of this application, but the protection scope of this application is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application fall within the protection and disclosure scope of this application.

Claims

1. A cylindrical lithium-ion battery with multiple tabs, characterized in that, The full-tab cylindrical lithium-ion battery includes a housing, a core and an electrolyte disposed inside the housing, the housing having an opening at one end along the axial direction, and a cap assembly disposed at one end of the opening; the core is formed by winding a negative electrode sheet, a separator and a positive electrode sheet arranged in sequence. The positive electrode sheet is divided into a positive electrode coating area and a positive electrode blank area along the width direction; the positive electrode blank area is flattened to form a positive electrode flattening layer, and the positive electrode flattening layer is connected to the cap assembly through the positive electrode current collector to form a positive electrode full-tab current collection path; The negative electrode sheet is divided into a negative electrode coating area and a negative electrode blank area along the width direction; the negative electrode blank area is flattened to form a negative electrode flattening layer, and the negative electrode flattening layer is connected to the bottom surface of the unopened end of the housing through the negative electrode current collector to form a negative electrode full-tab current collection path; The width W of the positive electrode coating area p The width W of the negative electrode coating region n Satisfies: 1.008≤W n / W p ≤1.045, W p With W n The unit is mm; The equivalent impedance R of the positive terminal omnipolar current collecting path top The equivalent impedance R of the current collection path of the negative terminal omnipolar tab bot Satisfy: ΔR end =|R top -R bot |<0.35mΩ, R top With R bot The unit is mΩ.

2. The all-tab cylindrical lithium-ion battery as described in claim 1, characterized in that, Taking the height H of the all-tab cylindrical lithium-ion battery as H, the temperature rise ΔT at the middle of the all-tab cylindrical lithium-ion battery at 1 / 2H in the height direction is... mid The temperature rise at the top of the cap assembly within a range of 5mm to 15mm is ΔT. top The temperature rise at the bottom within a range of 5mm to 15mm from the bottom surface of the casing is ΔT. bot ; Axial temperature difference ΔT of a full-tab cylindrical lithium-ion battery axial =max(ΔT top ,ΔT mid ,ΔT bot )-min(ΔT top ,ΔT mid ,ΔT bot Average temperature rise ΔT avg =(ΔT top +ΔT mid +ΔT bot ) / 3, temperature rise uniformity coefficient K Tu =ΔT axial / ΔT avg ΔT top ΔT mid and ΔT bot The unit is ℃; At 25°C and 100% SOC, constant current discharge at an 8C rate was performed until the voltage dropped to 2.5V or max(ΔT). top ,ΔT mid ,ΔT bot The cutoff temperature is 80℃. The fully tabbed cylindrical lithium-ion battery satisfies: ΔT axial ≤4.5℃, K Tu ≤0.13; And / or, at 25°C and 100% SOC, discharge at a constant current rate of 10C until the voltage drops to 2.5V or max(ΔT) top ,ΔT mid ,ΔT bot The cutoff temperature is 80℃. The fully tabbed cylindrical lithium-ion battery satisfies: ΔT axial ≤6.5℃, K Tu ≤0.16; And / or, at 25°C and 100% SOC, discharge at a constant current rate of 12C until the voltage drops to 2.5V or max(ΔT) top ,ΔT mid ,ΔT bot The cutoff temperature is 80℃. The fully tabbed cylindrical lithium-ion battery satisfies: ΔT axial ≤9℃, K Tu ≤0.

20.

3. The all-tab cylindrical lithium-ion battery as described in claim 1 or 2, characterized in that, The casing height H and diameter D of the full-tab cylindrical lithium-ion battery satisfy the following conditions: 64.7mm≤H≤65.5mm, 20.8mm≤D≤21.2mm, 3.06≤H / D≤3.14; The full-tab cylindrical lithium-ion battery has a discharge capacity of 4.9Ah to 5.2Ah at a 0.2C rate.

4. The all-tab cylindrical lithium-ion battery as described in any one of claims 1 to 3, characterized in that, The width W of the positive electrode coating area p The width W of the negative electrode coating area is 54.4mm~55.8mm. n The diameter is 55.4mm~57.0mm; The width W of the positive electrode coating area p The width W of the negative electrode coating region n Satisfies: 1.011≤W n / W p ≤1.

033.

5. The all-tab cylindrical lithium-ion battery as described in any one of claims 1 to 4, characterized in that, The width W of the positive electrode blank area pe The width W of the negative electrode blank area is 3.0mm~5.2mm. ne The thickness ranges from 2.5mm to 4.8mm. And / or, the thickness h of the positive electrode leveling layer p The thickness h of the negative electrode leveling layer is 0.08mm~0.18mm. n The thickness is 0.08mm to 0.18mm; And / or, the effective contact area A between the positive electrode leveling layer and the positive electrode current collector. pc 80mm 2 ~120mm 2 The effective contact area A between the negative electrode leveling layer and the negative electrode current collector is... nc 80mm 2 ~125mm 2 .

6. The all-tab cylindrical lithium-ion battery according to any one of claims 1 to 5, characterized in that, The equivalent impedance R of the positive terminal omnipolar current collecting path top The equivalent impedance R of the current collection path of the negative terminal omnipolar tab bot Satisfies: 0.08mΩ < ΔR end =|R top-Rbot |<0.25mΩ, R top With R bot The unit is mΩ.

7. The all-tab cylindrical lithium-ion battery according to any one of claims 1 to 6, characterized in that, The omni-tab cylindrical lithium-ion battery, under 25°C and 50% SOC, undergoes an 8C rate pulse discharge for 10 seconds, exhibiting a DC internal resistance (DCR) of [missing value]. 50 The resistance is 6.0mΩ to 9.0mΩ.

8. The all-tab cylindrical lithium-ion battery according to any one of claims 1 to 7, characterized in that, The positive electrode active material of the positive electrode includes LiNi. x Mn y A z O2, 0.88≤x≤0.93, 0<y≤0.12, 0≤z≤0.12, A includes Co and / or Al; And / or, the negative electrode active material of the negative electrode sheet includes graphite and / or silicon carbon; And / or, the electrolyte comprises a lithium salt, a carbonate solvent, and a film-forming additive, wherein the lithium salt comprises any one or a combination of at least two of LiPF6, LiFSI, or LiDFOB, and the film-forming additive comprises any one or a combination of at least two of VC, FEC, PS, DTD, or LiPO2F2.

9. A battery module, characterized in that, The battery module includes a full-tab cylindrical lithium-ion battery as described in any one of claims 1 to 8.

10. An electrical appliance, characterized in that, The electrical equipment includes a full-tab cylindrical lithium-ion battery as described in any one of claims 1 to 8, or includes a battery module as described in claim 9.

Images