Analysis of the performance decline discipline of lithium-ion power battery

Abstract

Prediction of state of health (SOH) of lithium-ion batteries can extend the service life of the batteries and improve the safe performance of the batteries, which is of great significance to research and development of lithium-ion batteries. Aiming at the problems that the discharge current of electric vehicles constantly changes under actual operating conditions and the number of full charge-discharge cycles is small, a battery health prediction model based on capacity decay rate is proposed. In this paper, the ternary cathode material power lithium-ion battery with a rated capacity of 5Ah is taken as the research subject, and the discharge experiment is conducted under the conditions of ambient temperature of 0 °C, 10 °C, 20 °C, 30 °C, and 40 °C. By fitting the curve of the battery capacity with the number of cycles, the decay rate of the battery capacity with the number of cycles is obtained.