Cylindrical soft package battery
By arranging the tabs on the side of the cell and extending them to the outside of the packaging film in cylindrical pouch batteries, the problem of tabs occupying axial space is solved, resulting in higher energy density and more stable cell winding, thus extending the battery's lifespan.
Patent Information
- Application Number
- CN202423074853.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-12
- Publication Date
- 2026-01-09
- Estimated Expiration
- 2034-12-12
AI Technical Summary
The tabs of cylindrical pouch batteries are arranged at both ends of the axial direction, resulting in high space occupancy, which reduces the energy density of the battery. Furthermore, the width direction of the tabs interferes with the winding of the cell, affecting the stability and cycle life of the cell.
The positive and negative tabs are arranged on the sides of the cell body and extend outside the packaging film. The improved packaging structure avoids the tabs occupying the end space. The design of folded diaphragm and multi-layer packaging film is used to stabilize the cell winding.
It improves the energy density of the battery and the winding stability of the cells, extends the cycle life of the battery, and enhances electrical performance.
Smart Images
Figure CN223785277U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to the technical field of batteries, in particular to a cylindrical soft-pack battery. BACKGROUND
[0002] As an energy source of electronic products, lithium ion batteries play an irreplaceable role in life. Among them, lithium ion cylindrical soft-pack batteries are widely used in small electronic products.
[0003] However, the tab of the cylindrical soft-pack battery in the related art is usually arranged at the axial two ends, and has the problems of high space occupancy and reduced energy density of the battery. CONTENT OF THE UTILITY MODEL
[0004] The application provides a cylindrical soft-pack battery, which can solve the problems of high space occupancy and reduced energy density of the battery caused by the arrangement of the tab at the axial two ends of the battery.
[0005] The technical solution is as follows:
[0006] A cylindrical soft-pack battery comprises a cylindrical battery core and a packaging film.
[0007] The cylindrical battery core comprises a battery core body, a positive tab and a negative tab.
[0008] The battery core body is cylindrical, and the positive tab and the negative tab are located on the side surface of the battery core body.
[0009] The packaging film is wrapped on the outer side of the battery core body, and at least part of the positive tab and the negative tab extends to the outside of the packaging film.
[0010] In some embodiments, the battery core body comprises a positive electrode sheet, a diaphragm and a negative electrode sheet which are sequentially stacked.
[0011] The positive tab is electrically connected with the positive electrode sheet, and the negative tab is electrically connected with the negative electrode sheet.
[0012] The positive electrode sheet and the negative electrode sheet are both rectangular.
[0013] The diaphragm is a double-layer structure formed by folding, the negative electrode sheet is located between the double-layer structure of the diaphragm, the positive electrode sheet is located on the outer side of the diaphragm, and the battery core body and the first folding line of the diaphragm are centrally wound to form.
[0014] In some embodiments, the diameter of the battery core body is 4.4-5.4 mm, and the axial length is 24-34 mm.
[0015] In some embodiments, the negative electrode tab includes a first end and a second end along a length direction, and the positive electrode tab includes a third end and a fourth end along the length direction;
[0016] The first end and the third end are respectively close to the first folding line;
[0017] The negative electrode ear is electrically connected with the second end and extends in a direction away from the first end, and the positive electrode ear is electrically connected with the fourth end and extends in a direction away from the third end.
[0018] In some embodiments, the positive electrode tab includes a positive electrode current collector on which a positive electrode material is coated, and the positive electrode ear is welded with the positive electrode current collector.
[0019] In some embodiments, the negative electrode tab includes a negative electrode current collector on which a negative electrode material is coated, and the negative electrode ear is welded with the negative electrode current collector.
[0020] In some embodiments, two groove structures are arranged on the packaging film, and the two groove structures are symmetrical about the second folding line of the packaging film;
[0021] The two groove structures are respectively close to the first edge of the packaging film.
[0022] When the packaging film is folded along the second folding line, the battery core body is located in a cylindrical cavity surrounded by the two groove structures, and the positive electrode ear and the negative electrode ear respectively extend to the outside of the first edge.
[0023] In some embodiments, the two layers of the packaging film around the cylindrical cavity are respectively heat-sealed.
[0024] In some embodiments, one end of the battery core body in an axial direction corresponds to the second folding line, and the other end of the battery core body in the axial direction corresponds to the first sealing edge structure of the packaging film; and the first sealing edge structure is bent and attached to the axial end surface of the battery core body.
[0025] In some embodiments, the packaging film includes a nylon layer, an aluminum foil layer and a heat-sealing layer which are stacked in sequence, and the heat-sealing layer is close to the battery core body.
[0026] The technical scheme provided in the application has at least the following beneficial effects:
[0027] The cylindrical soft package battery of the application, the positive and negative tabs are arranged on the side surface of the cylindrical cell body respectively, when the battery is hot-pressed and plasticized, the positive and negative tabs can extend to the outside of the plasticized film respectively, which is convenient for charging or discharging the cylindrical soft package battery. Since the positive and negative tabs are arranged on the side surface of the cell body, the positive and negative tabs will not occupy the end space of the cell body, and the axial length of the cell body can be further increased under the condition of unchanged external dimensions, thereby facilitating the improvement of the energy density of the cylindrical soft package battery. In addition, since the positive and negative tabs are arranged on the side surface of the cell body, compared with the scheme that the tabs are arranged on the axial end, the width size of the tab will not interfere with the winding direction of the cell body, and the winding stability of the cell body is better, which is beneficial to improve the cycle life and electrical performance of the cylindrical soft package battery. BRIEF DESCRIPTION OF DRAWINGS
[0028] In order to more clearly illustrate the technical solutions in the embodiments of the application, the drawings needed to be used in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor.
[0029] Figure 1 is a structural schematic diagram of the cylindrical soft package battery provided by the embodiment of the application;
[0030] Figure 2 is a structural sectional view of the cylindrical soft package battery provided by the embodiment of the application;
[0031] Figure 3 is a schematic diagram of the layer structure of the cell body provided by the embodiment of the application;
[0032] Figure 4 is a schematic diagram of the layer structure of the cell body provided by another embodiment of the application;
[0033] Figure 5 is a structural schematic diagram of the positive electrode sheet provided by the embodiment of the application;
[0034] Figure 6 is a structural schematic diagram of the negative electrode sheet provided by the embodiment of the application;
[0035] Figure 7 is a structural schematic diagram of the packaging film and the cylindrical cell provided by the embodiment of the application;
[0036] Figure 8 is a schematic diagram of the hot-pressing connection of the packaging film and the cylindrical cell provided by the embodiment of the application;
[0037] Figure 9 is a schematic diagram of the layer structure of the plasticized film provided by the embodiment of the application.
[0038] The reference signs in the drawings indicate the following:
[0039] 1. cylindrical battery cell;
[0040] 11. battery cell body; 111, positive electrode tab; 11101, third end; 11102, fourth end; 1111, positive current collector; 1112, positive electrode material; 112, separator; 1121, first folding line; 113, negative electrode tab; 11301, first end; 11302, second end; 1131, negative current collector; 1132, negative electrode material; 12, positive electrode lug; 13, negative electrode lug;
[0041] 2. packaging film;
[0042] 201, first edge;
[0043] 21, groove structure; 22, second folding line; 23, first edge sealing structure; 24, nylon layer; 25, aluminum foil layer; 26, heat sealing layer. DETAILED DESCRIPTION
[0044] The exemplary embodiments will be described in detail herein with reference to the attached drawings. In the following description, the same numbers are used to indicate the same or similar elements, unless otherwise represented. The embodiments described in the following exemplary embodiments do not represent all the implementations consistent with the present application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of the present application as detailed in the appended claims.
[0045] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application. Figure 1 The orientation or positional relationship shown is only for the purpose of facilitating the description of the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.
[0046] Unless otherwise defined, all technical terms used in the embodiments of the present application have the same meaning as commonly understood by one of ordinary skill in the art.
[0047] In the related art, the electrode lug of a cylindrical battery is usually located at the axial end of the battery cell, and such a cylindrical battery has the following disadvantages:
[0048] 1. The tabs occupy the axial end space of the cell, which prevents the cylindrical battery from making full use of the available space and thus fails to maximize its energy density.
[0049] 2. The axial ends of cylindrical batteries need to be sealed and connected with tabs, which further reduces the space utilization of cylindrical batteries.
[0050] 3. Since the tabs need to be built into the innermost layer of the core, and the tabs have certain width requirements, after the battery cell is wound, it will be affected by the stress in the width direction of the tabs, which will cause the battery cell to deform and thus affect the cycle life of the battery cell.
[0051] Therefore, this application provides a cylindrical pouch cell where the positive and negative tabs do not occupy the end space of the cell body. With the external dimensions unchanged, this is beneficial to improving the energy density of the cylindrical pouch cell. In addition, the width of the tabs does not interfere with the winding direction of the cell body, which is beneficial to improving the cycle life and electrical performance of the cylindrical pouch cell.
[0052] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.
[0053] Combination Figure 1 and Figure 2 As shown, this embodiment provides a cylindrical pouch battery, which includes a cylindrical cell 1 and a packaging film 2. The cylindrical cell 1 includes a cell body 11, a positive tab 12, and a negative tab 13; the cell body 11 is cylindrical, and the positive tab 12 and the negative tab 13 are respectively located on the side of the cell body 11; the packaging film 2 covers the outside of the cell body 11, and at least a portion of the positive tab 12 and the negative tab 13 extends to the outside of the packaging film 2.
[0054] In this embodiment of the cylindrical pouch battery, the positive tab 12 and the negative tab 13 are respectively arranged on the side of the cylindrical cell body 11. After the battery is heat-sealed, the positive tab 12 and the negative tab 13 can extend to the outside of the plastic film, which facilitates the charging or discharging of the cylindrical pouch battery. Since the positive tab 12 and the negative tab 13 are arranged on the side of the cell body 11, the positive tab 12 and the negative tab 13 will not occupy the end space of the cell body 11. Without changing the external dimensions, the axial length of the cell body 11 can be further increased, which is beneficial to improving the energy density of the cylindrical pouch battery.
[0055] Furthermore, since the positive tab 12 and negative tab 13 are arranged on the side of the cell body 11, compared with the scheme where the tabs are arranged at the axial end, the width of the tabs will not interfere with the winding direction of the cell body 11, and the winding stability of the cell body 11 is better, which is beneficial to improving the cycle life and electrical performance of the cylindrical soft-pack battery.
[0056] In combination Figure 3 And Figure 4 As shown in FIG. 1, in some embodiments, the battery cell body 11 comprises a positive electrode tab 111, a separator 112 and a negative electrode tab 113 which are sequentially stacked; the positive electrode tab 12 is electrically connected to the positive electrode tab 111, and the negative electrode tab 13 is electrically connected to the negative electrode tab 113.
[0057] Through the above arrangement, the positive electrode tab 12 and the negative electrode tab 13 are respectively electrically connected to the positive electrode tab 111 and the negative electrode tab 113 in the battery cell body 11, which can realize the charging and discharging of the cylindrical soft package battery.
[0058] In some possible implementations, the positive electrode tab 12 and the negative electrode tab 13 are any one of an aluminum strip structure, a nickel strip structure, a copper strip structure, an aluminum-nickel composite strip structure, and a copper-aluminum composite strip structure.
[0059] In some possible implementations, the separator 112 includes but is not limited to a polyethylene film, a polypropylene film, a polyethylene and polypropylene composite film, a polyethylene terephthalate non-woven fabric, a polyimide film, a ceramic coating film, and the like.
[0060] The positive electrode tab 111 and the negative electrode tab 113 are both rectangular; the separator 112 is a double-layer structure formed by folding, the negative electrode tab 113 is located between the double-layer structure of the separator 112, and the positive electrode tab 111 is located on the outside of the separator 112, and the battery cell body 11 is formed by winding around the first folding line 1121 of the separator 112.
[0061] Through the above arrangement, the positive electrode tab 111 and the negative electrode tab 113 are spaced apart by the separator 112, and then are formed by winding, so that the positive electrode tab 111 and the negative electrode tab 113 can generate an electrochemical reaction through the separator 112, thereby storing or releasing electrical energy.
[0062] In some possible implementations, the separator 112 is first folded along the first folding line 1121 to obtain a double-layer structure, a circular winding needle is inserted into the folded part of the separator 112, and the negative electrode tab 113 is inserted between the two layers of the separator 112. The circular winding needle is used for winding, the positive electrode tab 111 is inserted outside the separator 112 after winding 1.5 turns, and the winding is continued, and finally fixed by a finishing glue to obtain a winding core with a target diameter.
[0063] In some embodiments, the diameter of the battery cell body 11 is 4.4-5.4 mm, and the axial length is 24-34 mm. In this embodiment, since the positive electrode tab 12 and the negative electrode tab 13 do not occupy the end space of the battery cell body 11, the axial length of the battery cell body 11 is large, so that the energy density of the cylindrical soft package battery is high.
[0064] For example, the diameter of the battery cell body 11 is 4.9 mm, and the axial length is 29 mm.
[0065] In combination Figure 4 As shown in some embodiments, the negative electrode tab 113 includes a first end 11301 and a second end 11302 along the length direction, and the positive electrode tab 111 includes a third end 11101 and a fourth end 11102 along the length direction.
[0066] The first end 11301 and the third end 11101 are respectively close to the first folding line 1121 of the diaphragm 112; the negative tab 13 is electrically connected with the second end 11302 and extends in a direction away from the first end 11301, and the positive tab 12 is electrically connected with the fourth end 11102 and extends in a direction away from the third end 11101.
[0067] Through the above arrangement, the positive tab 12 and the negative tab 13 can be respectively electrically connected to the tail end of the positive electrode tab 111 and the negative electrode tab 113 in the winding direction, and when the battery core body 11 is wound, the positive tab 12 and the negative tab 13 can be located on the side of the battery core body 11, and the width direction of the positive tab 12 and the negative tab 13 is parallel to the axial direction of the battery core body 11, and the width direction of the positive tab 12 and the negative tab 13 does not interfere with the winding direction of the battery core body 11.
[0068] In some possible implementations, the positive tab 12 and the negative tab 13 are respectively connected to the positive electrode tab 111 and the negative electrode tab 113 before the winding of the winding core.
[0069] In combination Figure 5 As shown in some embodiments, the positive electrode tab 111 includes a positive current collector 1111, and the positive current collector 1111 is coated with a positive material 1112, and the positive tab 12 is welded to the positive current collector 1111.
[0070] During the charging process, lithium ions in the positive material 1112 are separated from the positive current collector 1111 and migrate to the negative electrode tab 113 through the electrolyte solution; during the discharging process, the lithium ions return to the positive electrode tab 111 from the negative electrode tab 113, and the positive material 1112 is reduced to obtain electrons, and the chemical energy is converted into electrical energy to provide power for the external circuit.
[0071] The positive current collector 1111 plays a role of collecting and conducting current, and optionally, the positive current collector 1111 is an aluminum foil structure. The aluminum foil has good electrical conductivity and corrosion resistance, and can effectively conduct the current generated by the positive active material to the external circuit of the battery.
[0072] In some possible implementations, the positive electrode material 1112 includes a positive electrode active material, a conductive agent, a binder, and the like. The positive electrode active material includes, but is not limited to, lithium cobaltate, lithium nickel manganese cobaltate, lithium iron, and the like. The conductive agent can improve the conductivity of the positive electrode active material, and includes carbon black, carbon fiber, graphene, and the like. These conductive agents can form a good conductive network between the active material particles, ensuring that electrons can be smoothly transmitted in the positive electrode sheet, thereby improving the charging and discharging efficiency of the battery. The binder has the function of bonding the particles of the positive electrode active material and the conductive agent together to form a stable whole, preventing the particles from falling off or loosening during the charging and discharging of the battery. Optionally, the binder includes polyvinylidene fluoride and the like.
[0073] In combination Figure 6 As shown in the figure, in some embodiments, the negative electrode sheet 113 includes a negative electrode current collector 1131, and a negative electrode material 1132 is coated on the negative electrode current collector 1131. The negative electrode tab 13 is welded to the negative electrode current collector 1131.
[0074] During the charging process, lithium ions migrate out of the positive electrode sheet 111 and are embedded in the active material of the negative electrode sheet 113. During the discharging process, lithium ions are released from the active material of the negative electrode sheet 113 and return to the positive electrode sheet 111. At the same time, the negative electrode active material loses electrons and undergoes an oxidation reaction, converting the stored chemical energy into electrical energy and releasing it.
[0075] The negative electrode current collector has the function of collecting and conducting current. Optionally, the negative electrode current collector is a copper foil structure. Because copper has good conductivity and can remain stable at the potential of the negative electrode, it can effectively collect and conduct current and transmit the current inside the battery to the external circuit.
[0076] In some possible implementations, the negative electrode material 1132 includes a negative electrode active material, a conductive agent, a binder, and the like. The negative electrode active material includes, but is not limited to, graphite, hard carbon, silicon-based materials, and the like. The conductive agent can improve the conductivity of the positive electrode active material, and includes carbon black, carbon fiber, graphene, and the like. These conductive agents can form a good conductive network between the active material particles, ensuring that electrons can be smoothly transmitted in the positive electrode sheet, thereby improving the charging and discharging efficiency of the battery. The binder has the function of bonding the particles of the positive electrode active material and the conductive agent together to form a stable whole, preventing the particles from falling off or loosening during the charging and discharging of the battery. Optionally, the binder includes sodium carboxymethyl cellulose and styrene butadiene rubber.
[0077] In combination Figure 7 And Figure 8 As shown in the figure, in some embodiments, the packaging film 2 is provided with two groove structures 21, and the two groove structures 21 are positionally symmetrical along the second folding line 22 of the packaging film 2. The two groove structures 21 are respectively close to the first edge 201 of the packaging film 2.
[0078] When the packaging film 2 is folded along the second folding line 22, the battery cell body 11 is located in the cylindrical cavity formed by the two groove structures 21, and the positive and negative electrode tabs 12 and 13 extend outside the first edge 201.
[0079] In this embodiment, the battery cell body 11 is arranged in the cylindrical cavity formed by the two groove structures 21 on the packaging film 2. Since the two groove structures 21 are close to the first edge 201 of the packaging film 2, when the battery cell body 11 is placed in the cylindrical cavity, the positive and negative electrode tabs 12 and 13 of the battery cell body 11 can extend outside the first edge 201.
[0080] Exemplarily, the depths of the two groove structures 21 can be the same or different.
[0081] In some embodiments, the depths of the two groove structures 21 are different, and the inner diameter of the cylindrical cavity formed by the two groove structures 21 is 4.5-5.5 mm, and the axial length of the cylindrical cavity is 25-35 mm.
[0082] When the depths of the two groove structures 21 meet the above requirements, the accommodation and limiting of the battery cell body 11 can be achieved. Before heat-seal plastic packaging, the battery cell body 11 can be first placed in the groove structure 21 with a larger depth, which facilitates the precise positioning of the battery cell body 11.
[0083] Exemplarily, the inner diameter of the cylindrical cavity is 5 mm, and the axial length is 30 mm.
[0084] In some embodiments, the length of the packaging film 2 is 63-73 mm, and the width is 35-45 mm. When the size of the packaging film 2 meets the above value range, the packaging film 2 can achieve reliable heat-seal plastic packaging of the battery cell body 11, the battery cell body 11 has sufficient heat-seal width around, and has sufficient area to arrange the air bag area to accommodate the gas discharged in the cylindrical cavity.
[0085] Exemplarily, the length of the packaging film 2 is 68 mm, and the width is 40 mm.
[0086] In combination with Figure 8 Exemplarily, in some embodiments, the two layers of packaging film 2 around the cylindrical cavity are respectively heat-sealed and connected. Through the above arrangement, the heat-seal connection of the packaging film 2 around the cylindrical cavity can achieve heat-seal plastic packaging of the battery cell body 11.
[0087] In combination with Figure 1 and Figure 8 Exemplarily, in some embodiments, one axial end of the battery cell body 11 corresponds to the second folding line 22, and the other axial end of the battery cell body 11 corresponds to the first edge sealing structure 23 of the packaging film 2; the first edge sealing structure 23 is bent and attached to the axial end face of the battery cell body 11.
[0088] Through the above arrangement, only one end of the axial direction of the battery core body 11 needs to be attached to the first sealing structure 23, and the other end only has one plastic coating layer. The space occupation of the axial end of the battery core body 11 is small, so that the axial length of the battery core body 11 can be increased under the condition that the external size is unchanged, thereby facilitating the improvement of the energy density of the cylindrical soft package battery.
[0089] In combination Figure 9 As shown in the figure, in some embodiments, the packaging film 2 includes a nylon layer 24, an aluminum foil layer 25 and a heat sealing layer 26 which are sequentially stacked, and the heat sealing layer 26 is close to the battery core body 11.
[0090] In this embodiment, the nylon layer 24 can also be called an outer layer, which has high strength, high toughness and other mechanical properties, and can provide good external protection for the cylindrical soft package battery. The aluminum foil layer 25 can also be called an intermediate layer, which has excellent barrier properties and has very high barrier ability to oxygen, water vapor, light and the like. At the same time, the aluminum foil also has good electrical conductivity and thermal conductivity, which can play a role in barrier protection, battery shielding and the like for the cylindrical soft package battery. The heat sealing layer 26 can also be called an inner layer, which can be mixed from a variety of polymer materials such as polyethylene or polypropylene, etc. These materials have good heat sealing properties, flexibility and chemical stability, and can play a role in sealing and packaging for the cylindrical soft package battery, and provide flexible support and protection for the battery core body 11.
[0091] In some possible implementation manners, the cylindrical soft package battery provided by the present application is applied to an electronic device, which can provide electric energy for electric devices in the electronic device.
[0092] The electronic device of the present embodiment includes portable terminal devices such as smartphones, tablet computers, MP3 (Moving Picture Experts Group Audio Layer III) players, MP4 (Moving Picture Experts Group Audio Layer IV) players, notebook computers or desktop computers, etc., and also includes other products such as electric shavers, electric toothbrushes, point-of-service terminals, wearable devices, and automotive, medical and industrial products.
[0093] It should be noted that, in the present application, unless specifically stated and limited otherwise, the "on" or "under" of a first feature to a second feature can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the "on", "above" and "above" of the first feature to the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The "under", "below" and "below" of the first feature to the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.
[0094] In the description of the present application, the description of the terms "certain embodiments", "one embodiment", "some embodiments", "illustrative embodiments", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in connection with the described embodiments or examples are included in at least one embodiment or example of the present application.
[0095] The above is only an embodiment of the present application, and is not used to limit the present application. Any modification, equivalent replacement, improvement, etc. made within the principles of the present application shall be included in the protection scope of the present application.
Claims
1. A cylindrical pouch battery, characterized by, The cylindrical soft package battery comprises a cylindrical battery core (1) and a packaging film (2); The cylindrical battery core (1) comprises a battery core body (11), a positive electrode tab (12) and a negative electrode tab (13); The battery core body (11) is cylindrical, and the positive electrode tab (12) and the negative electrode tab (13) are respectively located on the side surface of the battery core body (11); The packaging film (2) is wrapped on the outer side of the battery core body (11), and at least part of the positive electrode tab (12) and the negative electrode tab (13) extends to the outside of the packaging film (2). 2.The cylindrical pouch battery of claim 1, wherein, The battery core body (11) comprises a positive electrode tab (111), a diaphragm (112) and a negative electrode tab (113) which are sequentially stacked; The positive electrode tab (12) is electrically connected with the positive electrode tab (111), and the negative electrode tab (13) is electrically connected with the negative electrode tab (113); The positive electrode tab (111) and the negative electrode tab (113) are both rectangular; The diaphragm (112) is a double-layer structure formed by folding, the negative electrode tab (113) is located between the double-layer structure of the diaphragm (112), the positive electrode tab (111) is located on the outer side of the diaphragm (112), and the battery core body (11) is formed by winding around the first folding line (1121) of the diaphragm (112) as the center. 3.The cylindrical pouch battery of claim 2, wherein, The diameter of the battery core body (11) is 4.4-5.4mm, and the axial length is 24-34mm. 4.The cylindrical pouch battery of claim 3, wherein, The negative electrode tab (113) comprises a first end (11301) and a second end (11302) along the length direction, and the positive electrode tab (111) comprises a third end (11101) and a fourth end (11102) along the length direction; The first end (11301) and the third end (11101) are respectively close to the first folding line (1121); The negative electrode tab (13) is electrically connected with the second end (11302) and extends in a direction away from the first end (11301), and the positive electrode tab (12) is electrically connected with the fourth end (11102) and extends in a direction away from the third end (11101). 5.The cylindrical pouch battery of claim 1, wherein, Two recess structures (21) are arranged on the packaging film (2), and the two recess structures (21) are positionally symmetrical along the second folding line (22) of the packaging film (2); The two recess structures (21) are respectively close to the first edge (201) of the packaging film (2); When the packaging film (2) is folded along the second folding line (22), the battery core body (11) is located in a cylindrical cavity surrounded by the two recess structures (21), and the positive electrode tab (12) and the negative electrode tab (13) respectively extend to the outside of the first edge (201). 6.The cylindrical pouch battery of claim 5, wherein, The depths of the two recess structures (21) are different, and the inner diameter of the cylindrical cavity surrounded by the two recess structures (21) is 4.5-5.5mm, and the axial length of the cylindrical cavity is 25-35mm. 7.The cylindrical pouch battery of claim 5, wherein, The length of the packaging film (2) is 63-73mm, and the width is 35-45mm. 8.The cylindrical pouch battery of claim 7, wherein, Two layers of the packaging film (2) around the cylindrical cavity are respectively heat-sealed and connected. 9.The cylindrical pouch battery of claim 7, wherein, An axial one end of the battery cell body (11) corresponds to the second folding line (22), and an axial other end of the battery cell body (11) corresponds to a first sealing edge structure (23) of the packaging film (2); the first sealing edge structure (23) is bent and attached on an axial end surface of the battery cell body (11). 10.The cylindrical pouch battery of any one of claims 1 to 9, wherein, The packaging film (2) comprises a nylon layer (24), an aluminum foil layer (25) and a heat-sealing layer (26) which are sequentially stacked, and the heat-sealing layer (26) is close to the battery cell body (11).