Remaining capacity estimation of Li-ion batteries based on temperature sample entropy and particle filter

Currently, safety issue on Li-ion battery caused by thermal stability is one of the main factors that restricts its developmental application. In this paper, from a perspective of heat generation, we present a method to estimate remaining capacity of single Li-ion battery. Sample entropy (SampEn) is employed for the calculation of surface temperature in charging process and the relationship between SampEn and capacity fading in aging process is built. Considering various factors of capacity attenuation, an intelligent estimation approach is proposed by the combination of SampEn and particle filter (PF). •Relationship between surface temperature and discharge capacity is found via SampEn.•Functional relationship between multi-variables and discharge capacity is obtained.•A model of remaining capacity estimation based on SampEn and PF is proposed.•Estimation performs quite well on various operating conditions.