Mobile QR Code QR CODE : The Korean Institute of Power Electronics
Title Optimal Health Indicator Selection and Validation for Improving SOH Rapid Diagnosis Accuracy in Second-Life Applications of Used Batteries
Authors Ganghyeon Kook ; Miyoung Lee ; Dongcheol Lee ; Taehyeon Gong ; Jonghoon Kim
DOI https://doi.org/10.6113/TKPE.2025.30.1.45
Page pp.45-53
ISSN 1229-2214
Keywords Lithium-ion battery; Health indicator; State of health(SOH); Pearson correlation coefficient; Long short-term memory
Abstract The increasing occurrence of used batteries has highlighted the need for rapid and accurate state-of-health (SOH) estimation. However, rapid diagnostics can greatly diminish estimation accuracy. To address this challenge, this study introduces a health indicator (HI) that effectively reflects battery degradation during high-rate discharge processes. Voltage data from discharges at two different C-rate conditions were used to extract HI values for identifying the optimal HI, and multiple HIs were combined to enhance accuracy. Furthermore, the SOH estimation performance was evaluated by inputting the single and combined HIs with the highest correlation coefficients for each C-rate into a long short-term memory model.