A high-temperature formation process for high-voltage polymer lithium-ion batteries

Abstract

The invention discloses a high-temperature formation process of a high-voltage polymer lithium-ion battery, which comprises the following steps: (1) the battery is left standing at a high temperature of 45°C for 8-12 hours; (2) a pressure of 0.6Mpa-1.0Mpa is applied in a high-temperature pressure formation machine and bake at 75°C~85°C for 2‑3h; (3) after cooling down to 60°C~70°C, carry out chemical formation at a pressure of 0.2Mpa~0.4Mpa; Bake at a pressure of Mpa~1.0Mpa for 2 hours; (5) Take it out after cooling down to room temperature. The present invention adopts segmental temperature control and pressure high temperature pressure chemical formation and thermal compounding to realize stable pole piece / ceramic separator interface thermal compounding, which is beneficial to compound film-forming additives to form a stable SEI film on the surface of positive and negative electrode materials and improve the interface of the battery Stability, flatness and hardness, and significantly improve the high voltage resistance, high temperature resistance, cycle performance and safety performance of the battery.

Description

technical field [0001] The invention belongs to the technical field of polymer lithium-ion battery manufacturing, in particular to a high-voltage polymer lithium-ion battery high-temperature formation process. Background technique [0002] The charging cut-off voltage of polymer lithium-ion batteries for portable electronic products is generally 4.2V. In order to exert a higher capacity in a limited space and improve the energy density of polymer lithium-ion batteries, polymer lithium-ion batteries for portable electronic products mainly After trying to use positive and negative electrode materials with high specific capacity, high-energy electrolyte, ultra-thin separator (currently the thinnest industrialized film is 8 microns), thin copper foil (8 microns) and thin aluminum foil (10 microns), thin Aluminum-plastic packaging film (more than 70 microns), etc., when these measures are applied to the limit, people begin to pursue a higher charging cut-off voltage of polymer li...

AI Technical Summary

Problems solved by technology

[0004] However, since high-voltage polymer lithium-ion batteries are often designed with ultra-thin and high energy density, the requirements for flatness and hardness of the battery are very high.

In order to obtain good performance, the traditional liquid flexible packaging polymer lithium-ion battery often has a large amount of electrolyte perfusion, the battery is relatively soft, and the flatness is poor, and it is difficult to meet the hardness requirements of customers such as mobile phones and tablet computers. Therefore, it needs to be improved.

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