Life cycle capacity evaluation for battery energy storage systems
摘要
Based on the SOH definition of relative capacity, a whole life cycle capacity analysis method for battery energy storage systems is proposed in this paper. Due to the ease of data acquisition and the ability to characterize the capacity characteristics of batteries, voltage is chosen as the research object. Firstly, the first-order low-pass filtering algorithm, wavelet packet decomposition algorithm, and empirical mode decomposition algorithm are used to decompose the voltage data of complete battery charging and discharging cycles into high- and low-frequency bands; Furthermore, the Pearson correlation coefficient is applied to analyze the linear relationship between high-/low-frequency band voltage and capacity and to extract evaluation indicators related to capacity; Finally, the SOH evaluation accuracy of the proposed strategy through different application scenarios is verified to improve its generalization ability.