CN-122025728-A - Assembling method and packaging device for lean solution type lithium ion battery cell

CN122025728ACN 122025728 ACN122025728 ACN 122025728ACN-122025728-A

Abstract

The invention discloses an assembly method and a packaging device of a lean solution type lithium ion battery cell, wherein the method comprises the steps of obtaining a first area of the maximum end face of the battery cell to determine the number of strapping tapes, obtaining pressure required by the battery cell, width of the strapping tapes and a second area of a pressure plate, calculating preset pulling force applied by the strapping tapes based on the number of the strapping tapes, the width of the strapping tapes, the pressure required by the battery cell and the second area of the pressure plate, placing the battery cell between the two pressure plates, encircling the strapping tapes on the two pressure plates, applying the preset pulling force to the strapping tapes, locking the strapping tapes and packaging a packaging film. The invention improves the safety threshold of the battery core under the abusive condition, ensures the optimal pole piece-diaphragm interface contact through constant internal prestress, avoids completely different performance performances caused by different pressurizing modes at the PACK end, obviously prolongs the cycle life, improves the multiplying power performance and effectively inhibits lithium precipitation.

Inventors

LI KAIXUAN
ZHOU LIN
WANG KAIKAI
LI MING
ZHAO JIAOJIAO
HE HUA
ZHOU QUAN
ZHENG JIEYUN
YI GANG

Assignees

永康市高新技术产业研究院有限公司
长三角物理研究中心有限公司
中国科学院物理研究所

Dates

Publication Date: 20260512
Application Date: 20260116

Claims (9)

1. The assembling method of the lean solution type lithium ion battery cell is characterized by comprising the following steps of: Acquiring a first area of the maximum end face of a battery cell; determining the number of strapping tapes based on a first area of a maximum end face of the battery cell; acquiring the pressure required by the battery cell, the width of the strapping tape and the second area of the pressure plate; Calculating a preset tensile force applied by the strapping tape based on the number of the strapping tapes, the width of the strapping tapes, the pressure required by the battery cells and the second area of the pressure plate; placing a battery cell between two pressure plates; Wrapping the strapping tape around the two pressure plates, and applying a predetermined tension to the strapping tape; the strapping tape is locked and is put into the packaging film for packaging.
2. The method for assembling a lean solution type lithium ion battery cell according to claim 1, wherein the pressure required by the battery cell is 0.05 mpa-0.15 mpa.
3. The method for assembling a battery cell of a lean lithium ion battery according to claim 1, wherein the calculation formula of the preset tension applied by the strapping tape is: ; Wherein P is pressure, T is preset tension, x is the number of strapping tapes, S is the second area of the pressure plate, and H is the width of the strapping tapes.
4. The method of assembling a lean lithium ion battery cell of claim 1, wherein the strapping tape is constrained by an automatic packer and a fiber tape in combination with a ratchet tensioner.
5. The packaging device of the lean liquid type lithium ion battery cell is characterized by comprising two pressure plates, a plurality of strapping tapes and an automatic packer; The two pressure plates are respectively arranged on two sides of the battery cell, the inner wall of each pressure plate is attached to the outer wall of the battery cell, a plurality of strapping tapes are respectively sleeved outside the pressure plates, and the automatic packer is connected with the strapping tapes and used for controlling the pressure applied by the strapping tapes.
6. The packaging device for the battery cells of the lean-solution type lithium ion battery according to claim 5, wherein the pressure plate is an ABS plate or a PP plate.
7. The packaging device for the lean solution type lithium ion battery cell according to claim 5, further comprising limiting plates, wherein the cross sections of the limiting plates are triangular, the limiting plates are respectively arranged on two sides of the pressure plate, and long sides of the limiting plates are abutted with the battery cell.
8. The barren solution type lithium ion battery cell packaging device according to claim 5, wherein the thickness of the pressure plate is 0.05mm-0.1mm.
9. The lean lithium ion battery cell packaging device of claim 5, further comprising a fibrous tape wrapped around the exterior of the pressure plate.

Description

Assembling method and packaging device for lean solution type lithium ion battery cell Technical Field The invention relates to the technical field of lean solution type lithium ions, in particular to an assembly method and a packaging device of a lean solution type lithium ion battery cell. Background The battery cells of the soft-package battery and the battery cells of the aluminum-shell battery can generate a tiny gap between the pole piece and the diaphragm due to the volume change of the active material in the charging and discharging process. A great deal of researches and practices show that in the use process of the battery cell, proper external pressure is applied to the battery cell, so that the positive and negative plates and the diaphragm can be forced to be kept in close contact, thereby obviously reducing the internal resistance of the battery cell, improving the coulomb efficiency and prolonging the cycle life. In the prior art, heavy steel plates, high strength straps, or integral clamps are typically applied to the exterior of the assembled battery cell stack to provide the necessary pressure to the internal cell. The external pressurization mode has the inherent defects of 1, severely reducing the energy density, particularly for small modules, the heavy steel plates and the clamp are huge in weight, and the weight energy density and the volume energy density of the whole battery cell system are obviously reduced. 2. The pressure transmission is uneven and is easy to attenuate, the external pressure can be transmitted to each cell through a plurality of interfaces, the uneven pressure distribution is easy to be caused, in the long-term circulation, the originally set pressure can be attenuated, and the free electrolyte also increases the risk of battery leakage. Therefore, a method for assembling the battery cells of the lean lithium ion battery and a packaging device are needed to solve the defects of the prior art. Disclosure of Invention The invention aims to provide an assembling method of a lean solution type lithium ion battery cell and a novel technical scheme of a packaging device. According to a first aspect of the present invention, there is provided a method for assembling a battery cell of a lean solution type lithium ion battery, comprising the steps of: Acquiring a first area of the maximum end face of a battery cell; determining the number of strapping tapes based on a first area of a maximum end face of the battery cell; acquiring the pressure required by the battery cell, the width of the strapping tape and the second area of the pressure plate; Calculating a preset tensile force applied by the strapping tape based on the number of the strapping tapes, the width of the strapping tapes, the pressure required by the battery cells and the second area of the pressure plate; placing a battery cell between two pressure plates; Wrapping the strapping tape around the two pressure plates, and applying a predetermined tension to the strapping tape; the strapping tape is locked and is put into the packaging film for packaging. Further, the pressure required by the battery cell is 0.05-0.15 mPa. Further, the calculation formula of the preset tension applied by the strapping tape is as follows: ; Wherein P is pressure, T is preset tension, x is the number of strapping tapes, S is the second area of the pressure plate, and H is the width of the strapping tapes. Further, the binding belt is tightened to a preset tension by the automatic packer and the high-strength fiber tape in combination with the ratchet tensioner. According to a second aspect of the invention, there is provided a packaging device for a lean solution type lithium ion battery cell, comprising two pressure plates, a plurality of strapping tapes and an automatic packer; the two pressure plates are respectively arranged on two sides of the battery cell, the inner wall of each pressure plate is attached to the outer wall of the battery cell, a plurality of strapping tapes are respectively sleeved outside the pressure plates, and the automatic packer is connected with the strapping tapes and used for controlling the pressure applied by the strapping tapes. Further, the pressure plate is an ABS plate or a PP plate. Further, the packaging device of the lean solution type lithium ion battery cell further comprises a limiting plate, the cross section of the limiting plate is of a triangular structure, the limiting plates are respectively arranged on two sides of the pressure plate, and the long sides of the limiting plates are in butt joint with the battery cell. Further, the thickness of the pressure plate is 0.05mm-0.1mm. Further, the packaging device of the lean solution type lithium ion battery cell further comprises a fiber adhesive tape, and the fiber adhesive tape is wound on the outer portion of the pressure plate. The invention has the beneficial effects that: The method comprises the steps of firstly obtaining a fir