Formation method and preparation method of high-voltage lithium ion battery as well as battery

Abstract

The invention discloses a formation method and a preparation method of a high-voltage lithium ion battery as well as a battery. The formation method comprises steps as follows: (1), the battery is charged at constant current of 0.015C-0.05 C at limit voltage of 0.15 V-0.5 V and put aside for 10min-3h; (2), the battery is charged at constant current I2 of 0.05C-0.15 C at the limit voltage of 0.1V-0.4V, then charged at the constant voltage higher than mean voltage by 0.1V-0.4V at the limit current of a product of I2 and 0.1 and put aside for 10min-3h; (3), the battery is discharged for 0.5h-3h at constant current of 0.05-0.2 C and put aside for 10min-3h; (4), the battery is charged at the constant current I5 of 0.2C-1 C at the limit current U3 (the highest charge cut-off voltage), charged at the constant voltage U3 at the limit current of a product of I5 and 0.1, put aside for 5min-3h, discharged at the constant current I5 at the limit voltage U4 (the lowest discharge cut-off voltage) and put aside for 20min-3 h. By means of the method, a battery material is completely activated, and the compact and stable SEI film is formed.

Description

technical field [0001] The invention belongs to the technical field of lithium-ion batteries, and in particular relates to a formation method, a preparation method and a battery of a high-voltage lithium-ion battery. Background technique [0002] In recent years, with the rapid development and wide application of various portable electronic devices, wireless mobile communication devices and electric vehicles, people's demand for lithium-ion batteries with high specific energy, long life and low cost has become more urgent, and high-voltage cathode materials are becoming more and more important. has received increasing attention from researchers. The national "Energy Saving and New Energy Automobile Industry Development Plan 2012-2020" pointed out that by 2015, the specific energy of power battery modules will reach more than 150Wh / Kg. Although the application of high-voltage cathode materials can greatly increase the specific energy of the battery, the cycle performance and...

AI Technical Summary

Problems solved by technology

However, this is not suitable for high-voltage lithium-ion batteries. Long-term low current will cause excessive lithium ions to participate in the chemical reaction of SEI film formation, resulting in increased SEI film growth thickness, increased battery internal resistance, and long-term low current high voltage. The electrolyte is decomposed seriously, and the battery production cycle is long

Images