Cylindrical battery and preparation method therefor

Abstract

The present disclosure relates to the technical field of batteries. Provided are a cylindrical battery and a preparation method therefor. The cylindrical battery provided by the present disclosure comprises: jelly rolls, casings, an upper cover plate and a lower cover plate, wherein at least two jelly rolls are provided; the (n+1)th jelly roll is wound on an outer side wall of the nth jelly roll, where n is an integer greater than or equal to 1; adjacent jelly rolls are spaced apart by the casing; the casing wraps an outer side wall of the outermost jelly roll; and the upper cover plate is located on an upper bottom face of the jelly rolls, the lower cover plate is located on a lower bottom face of the jelly rolls, and the upper cover plate and the lower cover plate are sealingly connected to the casings, such that each jelly roll is located in a separate enclosed space. The cylindrical battery has a good heat dissipation performance, and thus the phenomenon of heat "accumulation" inside the battery is greatly reduced; and electrolytes having different functions can be injected into different jelly rolls, thereby reducing the phenomenon of the uneven performance degradation of the battery and prolonging the service life of the battery.

Description

Cylindrical battery and preparation method thereof

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure claims priority to Chinese patent application number 202311542976.7, filed with the State Intellectual Property Office of China on November 20, 2023, entitled “Cylindrical Battery and Its Preparation Method,” the entire contents of which are incorporated by reference into this disclosure. Technical Field

[0003] The present disclosure relates to the field of battery technology, and in particular to a cylindrical battery and a preparation method thereof. Background Art

[0004] As we all know, during the charge and discharge process, battery impedance consumes energy and generates irreversible heat. The optimal operating temperature for lithium-ion batteries is 20°C-35°C. Once the internal temperature rises, the battery life decreases exponentially with the increasing temperature gradient. In cylindrical batteries, due to their unique structure, the heat generated by charging and discharging cannot be dissipated promptly, resulting in uneven heat distribution. The temperature is higher near the center of the battery. This high temperature and uneven distribution lead to uneven degradation within the battery, significantly reducing the battery life.

[0005] In view of this, the present disclosure is proposed.

[0006] Summary of the Invention

[0007] A first object of the present disclosure is to provide a cylindrical battery to solve at least one of the above problems.

[0008] A second object of the present disclosure is to provide a method for preparing a cylindrical battery.

[0009] In a first aspect, the present disclosure provides a cylindrical battery comprising a wound cell, a housing, an upper cover plate, and a lower cover plate;

[0010] There are at least two wound battery cells; the (n+1)th wound battery cell is wound on the outer side wall of the (n)th wound battery cell, where n is an integer greater than or equal to 1; the casing is spaced between adjacent wound battery cells; and the outer side wall of the outermost wound battery cell is covered with the casing;

[0011] The upper cover is located on the upper bottom surface of the wound battery cell, and the lower cover is located on the lower bottom surface of the wound battery cell. The upper cover and the lower cover are respectively sealed to the shell, so that each wound battery cell is in a separate closed space.

[0012] As an optional technical solution, the wound battery cell is mainly obtained by winding a first separator, a positive electrode sheet, a second separator and a negative electrode sheet.

[0013] As an optional technical solution, the positive electrode active material of the positive electrode sheet includes ternary NCM, lithium iron phosphate or lithium cobalt oxide.

[0014] As an optional technical solution, the negative electrode active material of the negative electrode sheet includes graphite, hard carbon, soft carbon, silicon negative electrode or lithium titanate.

[0015] As an optional technical solution, the upper cover plate or the lower cover plate is provided with a liquid injection hole and an explosion-proof valve;

[0016] The injection hole is used for injecting electrolyte into the wound battery cell;

[0017] The explosion-proof valve is used for explosion-proofing the wound battery core.

[0018] As an optional technical solution, the shell includes an aluminum alloy shell or a nickel-plated steel shell.

[0019] As an optional technical solution, the wound battery cells are connected in parallel.

[0020] As an optional technical solution, the wound battery core is filled with electrolyte;

[0021] The electrolyte mainly consists of lithium salt, solvent and additives;

[0022] The lithium salt includes LiPF6 and LiFSI;

[0023] The solvent includes EC (ethylene carbonate), EMC (ethyl methyl carbonate), DMC (dimethyl carbonate) and PC (propylene carbonate);

[0024] The additives include VC (vinylene carbonate), DTD (ethylene sulfate), LiPO2F2 and FEC (fluoroethylene carbonate).

[0025] As an optional technical solution, the proportions of the components in the electrolyte of each wound battery cell are as follows:

[0026] y1=k×(-0.011ln(n)+0.1001), where k=0.9-1.05; 1 <n<1000; y2=0.14-y1; y3=30%×ω; y4=(-0.039ln(n)+0.351)×ω; y5=(0.0563ln(n)+0.301)×ω; y6=(1-y3-y4-y5)×ω; ω=1-y1-y2-y7-y8-y9-y10; y7=0.000032n 2-0.000485n+0.025452; y8=0.00235ln(n)+0.0002, y8≤1%; y9=-0.0005n+0.0025, 0≤y9≤0.2%; y10=0.3%; y1+y2+y3+y4+y5+y6+y7+y8+y9+y10=1;

[0027] Among them, y1 is the mass proportion of LiPF6; y2 is the mass proportion of LiFSI; y3 is the mass proportion of EC; y4 is the mass proportion of EMC; y5 is the mass proportion of DMC; y6 is the mass proportion of PC; y7 is the mass proportion of VC; y8 is the mass proportion of DTD; y9 is the mass proportion of LiPO2F2; y10 is the mass proportion of FEC.

[0028] In a second aspect, the present disclosure provides a method for preparing the cylindrical battery, comprising the following steps:

[0029] a. The first separator, the first negative electrode sheet, the first separator and the first positive electrode sheet of the first wound cell are wound on a winding needle to form a first wound cell, and then the first wound cell is loaded into a first housing;

[0030] b. The first separator, the first negative electrode sheet, the first separator and the first positive electrode sheet of the n+1th wound cell are wound on the nth wound cell to form the n+1th wound cell, and then the n+1th wound cell is loaded into the n+1th housing;

[0031] c. After all wound cells are manufactured, the upper and lower covers are welded, and cylindrical batteries are prepared after liquid injection and formation.

[0032] Compared with the prior art, the present disclosure has the following beneficial effects:

[0033] The cylindrical battery provided by the present disclosure isolates each wound cell into a separate enclosed space through a sealed connection between the casing and the upper and lower cover plates. Adjacent wound cells are separated by the casing. Heat generated by the wound cells in each space can be promptly dissipated through the casing, thereby reducing the overall heat generated in the battery and significantly reducing the phenomenon of "heat cohesion" in the battery, thereby extending the battery life.

[0034] The present invention can inject electrolytes with different functions into different wound battery cells, and truly play the role of prescribing the right medicine according to the heat generation characteristics of the battery, thereby reducing the phenomenon of uneven performance degradation of the battery and thus extending the battery life;

[0035] The present disclosure can achieve non-coexistence of liquids in the same battery system, greatly improving the phenomenon of battery performance degradation caused by natural defects in structural design of current batteries; it can realize long-life batteries in different application scenarios, and can meet the requirements of application scenarios through formulation, material combination, winding cell design, etc. in different wound cells, greatly avoiding the "natural defects" in the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the specific embodiments of the present disclosure or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0037] Figure 1 is a schematic cross-sectional view of a battery;

[0038] Figure 2 is a schematic diagram of the battery cover;

[0039] Figure 3 is a schematic diagram of the battery lower cover;

[0040] Figure 4 shows the battery temperature rise results;

[0041] Figure 5 shows the battery capacity retention results. DETAILED DESCRIPTION

[0042] The embodiments of the present disclosure will be described in detail below in conjunction with the embodiments and examples, but those skilled in the art will understand that the following embodiments and examples are only used to illustrate the present disclosure and should not be considered to limit the scope of the present disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present disclosure. If specific conditions are not specified, proceed according to conventional conditions or the conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0043] In a first aspect, the present disclosure provides a cylindrical battery comprising a wound cell, a housing, an upper cover plate, and a lower cover plate;

[0044] There are at least two wound battery cells; the (n+1)th wound battery cell is wound on the outer side wall of the (n)th wound battery cell, where n is an integer greater than or equal to 1; the casing is spaced between adjacent wound battery cells; and the outer side wall of the outermost wound battery cell is covered with the casing;

[0045] The upper cover is located on the upper bottom surface of the wound battery cell, and the lower cover is located on the lower bottom surface of the wound battery cell. The upper cover and the lower cover are respectively sealed to the shell, so that each wound battery cell is in a separate closed space.

[0046] The cylindrical battery disclosed herein isolates each wound cell into a separate, enclosed space through a sealed connection between the casing and upper and lower cover plates, with the casing separating adjacent wound cells. Because solid-solid thermal conductivity is superior to solid-gas thermal conductivity, the present disclosure utilizes the casing between the wound cells to enhance this solid-solid thermal conductivity. This allows the heat generated by the wound cells in each space to be promptly dissipated through the casing, thereby reducing the overall heat generated in the battery and significantly reducing the phenomenon of "heat cohesion" within the battery, thereby extending the battery's service life.

[0047] The present invention can inject electrolytes with different functions into different wound battery cells, and truly play the role of prescribing the right medicine according to the heat generation characteristics of the battery, thereby reducing the phenomenon of uneven performance degradation of the battery and thus extending the battery life;

[0048] The present disclosure can achieve non-coexistence of liquids in the same battery system, greatly improving the phenomenon of battery performance degradation caused by natural defects in structural design of current batteries; it can realize long-life batteries in different application scenarios, and can meet the requirements of application scenarios through formulation, material combination, winding cell design, etc. in different wound cells, greatly avoiding the "natural defects" in the battery.

[0049] In some optional embodiments, the wound battery cell is mainly obtained by winding a first separator, a positive electrode sheet, a second separator and a negative electrode sheet.

[0050] In some optional embodiments, the positive electrode active material of the positive electrode sheet includes but is not limited to ternary NCM, lithium iron phosphate or lithium cobalt oxide, or other positive electrode active materials well known in the art.

[0051] In some optional embodiments, the negative electrode active material of the negative electrode sheet includes but is not limited to graphite, hard carbon, soft carbon, silicon negative electrode or lithium titanate, or other negative electrode active materials well known in the art.

[0052] In some optional embodiments, the separator includes but is not limited to PE (polyethylene) or PP (polypropylene), or other battery separators well known in the art.

[0053] In some optional embodiments, the upper cover plate or the lower cover plate is provided with a liquid injection hole and an explosion-proof valve;

[0054] The injection holes are used to inject electrolyte into the wound battery cell, including the first injection hole, the second injection hole, the third injection hole, and the nth injection hole;

[0055] The explosion-proof valve is used for explosion-proofing of wound battery cells, and includes a first explosion-proof valve, a second explosion-proof valve, a first explosion-proof valve, and an nth explosion-proof valve.

[0056] It should be noted that, since the wound battery cells are separated from each other, in order to achieve liquid injection and explosion protection for each wound battery cell, a corresponding liquid injection hole and explosion-proof valve need to be designed for each wound battery cell.

[0057] In some optional embodiments, the upper cover plate and the lower cover plate are welded to the shell to form a first welding area, a second welding area, a third welding area, and an nth welding area.

[0058] In some optional embodiments, the shell includes an aluminum alloy shell or a nickel-plated steel shell.

[0059] In some optional embodiments, the wound battery cells are connected in parallel.

[0060] In this disclosure, conventional connection methods in the art can be used to connect the tabs of the wound cell to the cover. For example, the positive tab of the wound cell can be welded to the current collector plate and then connected to the positive cover plate via a connecting piece; the negative tab of the wound cell can be welded to the current collector plate and then connected to the negative cover plate via a connecting piece.

[0061] In some optional embodiments, the wound battery core is filled with an electrolyte;

[0062] The electrolyte mainly consists of lithium salt, solvent and additives;

[0063] The lithium salt includes LiPF6 and LiFSI;

[0064] The solvent includes EC (ethylene carbonate), EMC (ethyl methyl carbonate), DMC (dimethyl carbonate) and PC (propylene carbonate);

[0065] The additives include VC (vinylene carbonate), DTD (ethylene sulfate), LiPO2F2 and FEC (fluoroethylene carbonate).

[0066] In some optional embodiments, the proportions of the components in the electrolyte of each wound battery cell are as follows:

[0067] y1=k×(-0.011ln(n)+0.1001), where k=0.9-1.05; 1 <n<1000; y2=0.14-y1; y3=30%×ω; y4=(-0.039ln(n)+0.351)×ω; y5=(0.0563ln(n)+0.301)×ω; y6=(1-y3-y4-y5)×ω; ω=1-y1-y2-y7-y8-y9-y10; y7=0.000032n2 -0.000485n+0.025452; y8=0.00235ln(n)+0.0002, y8≤1%; y9=-0.0005n+0.0025, 0≤y9≤0.2%; y10=0.3%; y1+y2+y3+y4+y5+y6+y7+y8+y9+y10=1;

[0068] Among them, y1 is the mass proportion of LiPF6; y2 is the mass proportion of LiFSI; y3 is the mass proportion of EC; y4 is the mass proportion of EMC; y5 is the mass proportion of DMC; y6 is the mass proportion of PC; y7 is the mass proportion of VC; y8 is the mass proportion of DTD; y9 is the mass proportion of LiPO2F2; y10 is the mass proportion of FEC.

[0069] In a second aspect, the present disclosure provides a method for preparing the cylindrical battery, comprising the following steps:

[0070] a. The first separator, the first negative electrode sheet, the first separator and the first positive electrode sheet of the first wound cell are wound on the winding needle to form a first wound cell (a center hole is formed after the winding needle is pulled out), and then the first wound cell is loaded into the first housing;

[0071] b. The first separator, the first negative electrode sheet, the first separator and the first positive electrode sheet of the n+1th wound cell are wound on the nth wound cell to form the n+1th wound cell, and then the n+1th wound cell is loaded into the n+1th housing;

[0072] c. After all wound cells are manufactured, the upper and lower covers are welded, and cylindrical batteries are prepared after liquid injection and formation.

[0073] The preparation method provided by the present disclosure is simple and convenient, and the cylindrical battery prepared has good heat dissipation and a long service life.

[0074] The present disclosure is further illustrated below through specific examples and comparative examples. However, it should be understood that these examples are merely used for more detailed description and should not be construed as limiting the present disclosure in any form.

[0075] Example 1

[0076] A cylindrical battery, as shown in Figures 1 to 3, includes a wound battery cell, a shell, an upper cover plate and a lower cover plate;

[0077] The wound battery cell is mainly obtained by winding a first separator, a positive electrode sheet, a second separator and a negative electrode sheet; there are three wound battery cells, and each battery cell is connected in parallel; the second wound battery cell is wound on the outer wall of the first wound battery cell; the third wound battery cell is wound on the outer wall of the second wound battery cell; a shell is placed between adjacent wound battery cells; the outer wall of the outermost wound battery cell is covered with the shell;

[0078] Among them, the positive electrode sheet is a lithium iron phosphate positive electrode sheet; the negative electrode sheet is a graphite negative electrode sheet; the diaphragm is a PP diaphragm; the shell is an aluminum alloy shell;

[0079] The upper cover is located on the upper bottom surface of the wound battery cell, and the lower cover is located on the lower bottom surface of the wound battery cell. The upper cover and the lower cover are respectively sealed and welded to the shell, so that each wound battery cell is in a separate enclosed space; the upper cover is provided with a corresponding injection hole and explosion-proof valve for each wound battery cell;

[0080] The proportions of the components in the electrolyte of each wound cell are shown in Table 1.

[0081] The preparation method is as follows:

[0082] a. The first separator, the first negative electrode sheet, the first separator and the first positive electrode sheet of the first wound cell are wound on a winding needle to form a first wound cell, and then the first wound cell is loaded into a first housing;

[0083] b. The first separator of the second wound cell, the first negative electrode sheet, the first separator and the first positive electrode sheet are wound on the first wound cell to form a second wound cell, and then the second wound cell is loaded into the second housing;

[0084] c. The first separator, the first negative electrode sheet, the first separator and the first positive electrode sheet of the third wound cell are wound on the second wound cell to form a third wound cell, and then the third wound cell is loaded into the third housing;

[0085] d. After all the wound cells are manufactured, the upper and lower covers are welded, and the cylindrical batteries are prepared after liquid injection and formation.

[0086] Conventional methods can be used to connect the winding battery cell tabs and the cover plate.

[0087] Example 2

[0088] A cylindrical battery, which differs from Example 1 in that the composition ratios of the components in the electrolyte of each wound battery cell are different, and the composition ratios are shown in Table 1.

[0089] Example 3

[0090] A cylindrical battery, which differs from Example 1 in that the composition ratios of the components in the electrolyte of each wound battery cell are different, and the composition ratios are shown in Table 1.

[0091] Table 1

[0092] Comparative Example 1

[0093] A cylindrical battery, which differs from Example 1 in that no shell is provided between the wound battery cells, and the electrolyte adopts the electrolyte of the first wound battery cell in Example 1.

[0094] Comparative Example 2

[0095] A cylindrical battery, which differs from Example 1 in that no shell is provided between the wound battery cells, and the electrolyte adopts the electrolyte of the second wound battery cell in Example 1.

[0096] Comparative Example 3

[0097] A cylindrical battery, which differs from Example 1 in that no shell is provided between the wound battery cells, and the electrolyte adopts the electrolyte of the third wound battery cell in Example 1.

[0098] Example 4

[0099] A cylindrical battery, which differs from Example 1 in that the electrolyte of each wound battery cell adopts the electrolyte of the second wound battery cell in Example 1.

[0100] Test Example 1

[0101] The battery cells provided in Examples 1-4 and Comparative Examples 1-3 were tested. The battery cell system was an LFP / Gr system, and the battery cell nominal capacity was 10 Ah. The test contents and results are as follows:

[0102] 1. The battery cell was discharged from 100% SOC to 2.5V at 1.0C at 25°C. The battery cell temperature rise results are shown in Figure 4.

[0103] As can be seen from Figure 4, the battery cells provided by Examples 1-4 have a lower temperature rise than the battery cells of Comparative Examples 1-3, indicating that the battery cells provided by the present disclosure further improve the heat dissipation performance of the battery cells by setting the shell between the wound battery cells; the temperature of the battery cells of Examples 1-3 is lower than that of Example 4, indicating that the present disclosure can further improve the heat dissipation effect of the battery by designing an electrolyte that matches the battery based on the heat generation characteristics of the battery.

[0104] 2. The battery cell was charged and discharged at 1.0C at 25°C, with a charge cut-off voltage of 3.65V and a discharge cut-off voltage of 2.5V. The test results are shown in Figure 5.

[0105] As can be seen from the figure, the capacity retention rate: the battery cells provided by Examples 1-4 have a higher capacity retention rate than the battery cells provided by Comparative Examples 1-3 when the number of cycles is the same, indicating that the battery cells provided by the present disclosure further improve the cycle life of the battery cells by setting the shell between the wound battery cells; the capacity retention rate of the battery cells of Examples 1-3 at 2400 weeks is higher than that of Example 4, indicating that the present disclosure can further improve the cycle life of the battery according to the electrolyte designed to match the battery.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure, rather than to limit them. Although the present disclosure has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present disclosure. Industrial Applicability

[0107] The present disclosure provides a cylindrical battery and a preparation method thereof, which relate to the field of battery technology. The cylindrical battery provided by the present disclosure includes a wound battery cell, a shell, an upper cover plate and a lower cover plate; there are at least two wound battery cells; the n+1th wound battery cell is wound on the outer side wall of the nth wound battery cell, and n is an integer greater than or equal to 1; the shell is spaced between adjacent wound battery cells; the outer side wall of the outermost wound battery cell is covered with the shell; the upper cover plate is located on the upper bottom surface of the wound battery cell, and the lower cover plate is located on the lower bottom surface of the wound battery cell. The upper cover plate and the lower cover plate are respectively sealed with the shell, so that each wound battery cell is in a separate enclosed space. The cylindrical battery has good heat dissipation and greatly reduces the phenomenon of "cohesion" of battery heat; electrolytes with different functions can be injected into different wound battery cells to reduce the phenomenon of uneven performance attenuation of the battery and increase the service life of the battery.

[0108] Furthermore, it is understood that the cylindrical battery and its preparation method disclosed herein are reproducible and can be used in a variety of industrial applications. For example, the cylindrical battery and its preparation method disclosed herein can be used in the field of battery technology.

Claims

1. A cylindrical battery, characterized in that, it comprises a wound battery cell, a housing, an upper cover plate and a lower cover plate; there are at least 2 wound battery cells; the (n + 1)-th wound battery cell is wound on the outer side wall of the n-th wound battery cell, where n is an integer greater than or equal to 1; there is a space of the housing between adjacent wound battery cells; the outer side wall of the outermost wound battery cell is covered with the housing; the upper cover plate is located on the upper bottom surface of the wound battery cell, and the lower cover plate is located on the lower bottom surface of the wound battery cell. The upper cover plate and the lower cover plate are respectively sealed and connected to the housing, so that each wound battery cell is in a separate enclosed space.

2. The cylindrical battery according to claim 1, characterized in that, the wound battery cell is mainly obtained by winding a first separator, a positive electrode sheet, a second separator and a negative electrode sheet.

3. The cylindrical battery according to claim 2, characterized in that, the positive electrode active material of the positive electrode sheet includes ternary NCM, lithium iron phosphate or lithium cobaltate.

4. The cylindrical battery according to claim 2, characterized in that, the negative electrode active material of the negative electrode sheet includes graphite, hard carbon, soft carbon, silicon negative electrode or lithium titanate.

5. The cylindrical battery according to claim 1, characterized in that, a liquid injection hole and an explosion-proof valve are provided on the upper cover plate or the lower cover plate; the liquid injection hole is used for injecting electrolyte into the wound battery cell; the explosion-proof valve is used for explosion-proof of the wound battery cell.

6. The cylindrical battery according to claim 1, characterized in that, the housing includes an aluminum alloy shell or a nickel-plated steel shell.

7. The cylindrical battery according to claim 1, characterized in that, each wound battery cell is connected in parallel.

8. The cylindrical battery according to claim 1, characterized in that, the wound battery cell is filled with electrolyte; the electrolyte is mainly composed of a lithium salt, a solvent and an additive; The lithium salt includes LiPF 6 and LiFSI; the solvent includes EC, EMC, DMC and PC; The additives include VC, DTD, LiPO 2 F 2 and FEC.

9. The cylindrical battery according to claim 7, characterized in that, the component ratios of each component in the electrolyte of each wound battery cell are as follows: y1 = k×(-0.011ln(n)+0.1001), where k = 0.9 - 1.05; 1 < n < 1000; y2 = 0.14 - y1; y3 = 30%×ω; y4 = (-0.039ln(n)+0.351)×ω; y5 = (0.0563ln(n)+0.301)×ω; y6 = (1 - y3 - y4 - y5)×ω; ω = 1 - y1 - y2 - y7 - y8 - y9 - y10; y7 = 0.000032n 2 -0.000485n + 0.025452; y8 = 0.00235ln(n)+0.0002, y8 ≤ 1%; y9 = -0.0005n + 0.0025, 0 ≤ y9 ≤ 0.2%; y10＝0.3％； y1 + y2 + y3 + y4 + y5 + y6 + y7 + y8 + y9 + y10 = 1; where y1 is the mass fraction of LiPF 6 ; y2 is the mass fraction of LiFSI; y3 is the mass fraction of EC; y4 is the mass fraction of EMC; y5 is the mass fraction of DMC; y6 is the mass fraction of PC; y7 is the mass fraction of VC; y8 is the mass fraction of DTD; y9 is the mass fraction of LiPO 2 F 2 ; y10 is the mass fraction of FEC.

10. The preparation method of the cylindrical battery according to any one of claims 1 - 9, characterized in that, it comprises the following steps: a. Winding a first separator, a first negative electrode sheet, a first separator and a first positive electrode sheet on a winding needle to form a first wound battery cell, and then loading the first wound battery cell into a first housing; b. Wind the first separator, the first negative electrode sheet, the first separator, and the first positive electrode sheet of the (n + 1)-th wound battery cell around the n-th wound battery cell to form the (n + 1)-th wound battery cell, and then place the (n + 1)-th wound battery cell into the (n + 1)-th housing; c. After all the wound battery cells are fabricated, weld the upper cover plate and the lower cover plate. After liquid injection and formation, a cylindrical battery is prepared.

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