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CN-122000421-A - Battery monomer, preparation method thereof, battery and power utilization device

CN122000421ACN 122000421 ACN122000421 ACN 122000421ACN-122000421-A

Abstract

The application belongs to the technical field of batteries, and discloses a battery monomer, a preparation method thereof, a battery and an electric device. The lithium ion battery comprises a shell, an electrode assembly, a binding assembly, a first functional layer, a first functional material and a second functional material, wherein the electrode assembly is arranged in a containing cavity of the shell and comprises a first surface, a second surface and a third surface, a first insulating part of an insulating part covers the first surface, a second insulating part of the insulating part covers the second surface, a base film layer of the binding assembly is adhered to one side, away from the electrode assembly, of the first insulating part through a first bonding layer and one side, away from the electrode assembly, of the second insulating part through a second bonding layer, the first functional layer of the binding assembly is arranged corresponding to the third surface, the first functional layer comprises a first functional material which is in a shell-core structure, the first functional material comprises an inner core and a shell layer positioned on the surface of the inner core, the glass transition temperature of the shell layer is 70-120 ℃, the inner core expands in volume within the range of 70-130 ℃, and the volume expansion ratio is 5-60 times.

Inventors

  • YU HONGJIANG
  • CHENG SHIPING
  • GAO YONG
  • LIN WEIMIN
  • SHEN XIN
  • WANG RUI

Assignees

  • 江苏正力新能电池技术股份有限公司

Dates

Publication Date
20260508
Application Date
20260129

Claims (10)

  1. 1.A battery cell, comprising: a housing assembly (1) comprising a receiving cavity (11); An electrode assembly (2) disposed in the accommodating cavity (11), wherein the electrode assembly (2) comprises a first surface (21), a second surface (22) and a third surface (23), the first surface (21) and the second surface (22) are oppositely disposed in a first direction (X), the third surface (23) is a surface of the electrode assembly (2) in a second direction (Y) and is connected between the first surface (21) and the second surface (22), the first direction (X) is a thickness direction of the electrode assembly (2), and the second direction (Y) is a length direction of the electrode assembly (2); an insulator (3) comprising a first insulating portion (31) and a second insulating portion (32), the first insulating portion (31) covering the first surface (21) and the second insulating portion (32) covering the second surface (22); The restraint assembly (4) comprises a base film layer (41), a first bonding layer (42), a second bonding layer (43) and a first functional layer (44), wherein the first bonding layer (42), the second bonding layer (43) and the first functional layer (44) are arranged on one side of the base film layer (41) facing towards the electrode assembly (2), the base film layer (41) is bonded on one side of the first insulating part (31) facing away from the electrode assembly (2) through the first bonding layer (42), the second insulating part (32) is bonded on one side of the second insulating part (32) facing away from the electrode assembly (2) through the second bonding layer (43), the first functional layer (44) is arranged between the first bonding layer (42) and the second bonding layer (43) and corresponds to the third surface (23), the first functional layer (44) comprises a first functional material which is a shell core structure, the first functional material comprises a core (441) and a shell layer (442) positioned on the surface of the core (441), and the glass transition temperature of the first functional layer (442) is 70 ℃ and expansion volume of the first functional layer (44) is configured to be between 60 ℃ and 60 ℃ when the glass transition temperature of the core layer (442) is configured to be between 60 ℃ and a volume multiple of expansion temperature of the core (60 ℃ and between 60 ℃ and 60 ℃.
  2. 2. The battery cell of claim 1, wherein the material of the shell layer (442) comprises at least one of polystyrene, acrylic, polymethyl methacrylate, polyurethane; and/or the number of the groups of groups, The material of the inner core (441) includes at least one of n-hexane, cyclohexane, methanol, ethanol, and isopropanol.
  3. 3. The battery cell according to claim 1 or 2, wherein the tie-down assembly (4) further comprises a second functional layer (45), the second functional layer (45) being arranged on a side of the first functional layer (44) facing away from the base film layer (41); The second functional layer (45) comprises a second functional material, and the second functional material comprises at least one of polymer foam, aerogel, carbon adsorption material, inorganic adsorption material and composite adsorption material; Preferably, the second functional material comprises high molecular foam; preferably, the second functional material comprises polyurethane foam; preferably, the thickness of the second functional layer (45) is c, wherein c is more than or equal to 0.2mm and less than or equal to 1mm.
  4. 4. The battery cell according to claim 1 or 2, wherein an end face of the restraint assembly (4) in a third direction (Z) is flush with an end face of the electrode assembly (2) in the third direction (Z), or an end face of the restraint assembly (4) in the third direction (Z) exceeds an end face of the electrode assembly (2) in the third direction (Z) by a first distance a, wherein a is less than or equal to 1mm; Wherein the third direction (Z) is perpendicular to both the first direction (X) and the second direction (Y).
  5. 5. The battery cell of claim 1, wherein: The thickness of the first functional layer (44) is b, wherein b is more than or equal to 0.01mm and less than or equal to 5mm; And/or the thickness of the base film layer (41) is d, wherein d is more than or equal to 0.01mm and less than or equal to 0.1mm; and/or the thickness of the first adhesive layer (42) is e, wherein e is more than or equal to 10 mu m and less than or equal to 200 mu m; And/or the thickness of the second adhesive layers (43) is f, wherein f is more than or equal to 10 mu m and less than or equal to 200 mu m, and preferably, e=f.
  6. 6. The battery cell of claim 1, wherein the tie assembly (4) further comprises a third adhesive layer (46), the first functional layer (44) being adhered to the base film layer (41) by the third adhesive layer (46).
  7. 7. A method for preparing a battery cell according to any one of claims 1 to 6, comprising the steps of: Covering a first insulating portion (31) of the insulating member (3) on a first surface (21) of the electrode assembly (2), and covering a second insulating portion (32) of the insulating member (3) on a second surface (22) of the electrode assembly (2); bonding a base film layer (41) of a binding assembly (4) to one side of a first insulating part (31) which faces away from the electrode assembly (2) through a first bonding layer (42), and bonding to one side of a second insulating part (32) which faces away from the electrode assembly (2) through a second bonding layer (43), wherein a first functional layer (44) is positioned between the base film layer (41) and a third surface (23) of the electrode assembly (2); Placing the assembled electrode assembly (2), the insulator (3) and the binding assembly (4) into a containing cavity (11) of a shell assembly (1), and sealing the containing cavity (11) after one-time liquid injection; baking the housing assembly (1) to expand the first functional layer (44) of the restraint assembly (4) and fill the gap between the third surface (23) and the base film layer (41) to obtain a battery cell.
  8. 8. The method of producing a battery cell according to claim 7, wherein the temperature at which the housing assembly (1) is baked is 80 ℃ to 120 ℃.
  9. 9. A battery, characterized in that the battery comprises the battery cell according to any one of claims 1 to 6, or the battery comprises the battery cell prepared by the preparation method of the battery cell according to claim 7 or 8.
  10. 10. An electric device, characterized in that the electric device comprises the battery as claimed in claim 9, or the electric device comprises the battery cell as claimed in any one of claims 1-6, or the electric device comprises the battery cell prepared by the preparation method of the battery cell as claimed in claim 7 or 8.

Description

Battery monomer, preparation method thereof, battery and power utilization device Technical Field The present invention relates to the field of battery technologies, and in particular, to a battery unit, a method for manufacturing the battery unit, a battery, and an electric device. Background The two ends of the rolled core battery in the width direction form bending parts, the bending parts can also be called as R angles of the rolled core battery, the outer shell of the battery is generally of a square shell structure, and a large gap exists between the bending parts of the rolled core and the inner wall of the outer shell. And larger gaps exist between the positive plate and the diaphragm at the bending part, between the negative plate and the diaphragm, and between the positive plate and the negative plate. In the battery charging and discharging process, particularly in the quick charging and charging process, larger gaps between the positive plate and the diaphragm, between the negative plate and the diaphragm, and between the positive plate and the negative plate can lead to longer lithium ion migration paths and increase migration resistance, so that concentration polarization and electrochemical polarization are further increased, serious lithium precipitation problems can be caused, and the service life is shorter. Disclosure of Invention The first aim of the application is to provide a battery cell to solve the technical problems of serious lithium precipitation and short service life. The second object of the present application is to provide a method for preparing a battery cell, which is easy to operate and can alleviate the problem of lithium precipitation. A third object of the present application is to provide a battery capable of having a long service life. The fourth object of the present application is to provide an electric device with high safety. The technical scheme adopted by the application is as follows: a battery cell comprising: A housing assembly including a receiving cavity; The electrode assembly is arranged in the accommodating cavity, and comprises a first surface, a second surface and a third surface, wherein the first surface and the second surface are oppositely arranged in a first direction, the third surface is a surface of the electrode assembly in a second direction and is connected between the first surface and the second surface, the first direction is the thickness direction of the electrode assembly, and the second direction is the length direction of the electrode assembly; an insulating member including a first insulating portion covering the first surface and a second insulating portion covering the second surface; The binding assembly comprises a base film layer, a first binding layer, a second binding layer and a first functional layer, wherein the first binding layer, the second binding layer and the first functional layer are arranged on one side of the base film layer, which faces the electrode assembly, the base film layer is adhered to one side of the first insulating part, which faces away from the electrode assembly, through the first binding layer, and is adhered to one side of the second insulating part, which faces away from the electrode assembly, through the second binding layer, the first functional layer is arranged between the first binding layer and the second binding layer and corresponds to the third surface, the first functional layer comprises a first functional material, the first functional material is of a shell core structure, the first functional material comprises an inner core and a shell layer, the shell layer is positioned on the surface of the inner core, the glass transition temperature of the shell layer is 70-120 ℃, and the inner core is configured to expand in volume when the temperature is in the range of 70-130 ℃, and the volume expansion multiple is 5-60 times. In one or more embodiments of the present application, the material of the shell layer includes at least one of polystyrene, acrylic resin, polymethyl methacrylate, polyurethane; and/or the number of the groups of groups, The material of the inner core comprises at least one of normal hexane, cyclohexane, methanol, ethanol and isopropanol. In one or more embodiments of the present application, the tie-down assembly further includes a second functional layer disposed on a side of the first functional layer facing away from the base film layer; The second functional layer comprises a second functional material, and the second functional material comprises at least one of polymer foam, aerogel, carbon adsorption materials, inorganic adsorption materials and composite adsorption materials; Preferably, the second functional material comprises high molecular foam; preferably, the second functional material comprises polyurethane foam; Preferably, the thickness of the second functional layer is c, wherein c is more than or equal to 0.2mm and less than or equal to 1mm. In