https://doi.org/10.5370/KIEE.2024.73.9.1535
신건(Jian Shen) ; 유현상(Hyun-Sang You) ; 박찬욱(Chan-Wook Park) ; 최성문(Sung-Moon Choi) ; 노대석(Dae-Seok Rho)
The estimation method of the lifespan in VRFB for ESS based on general operation data is required as the evaluation on deterioration characteristics is time-consuming and costly. Therefore, this paper implements a deterioration cycle test device of VRFB for ESS, which is composed of VRFB, internal impedance measurement device, monitoring and control sections, and performs accelerated aging test for 2,500 cycles and analyzes the deterioration characteristics of charging-discharging energy efficiency, internal impedance, slope of OCV variation and potentio-metric titration, which are the key index to evaluate the deterioration degree in VRFB. Based on the above-mentioned test results, deterioration prediction models for VRFB by mathematical formalization using linear regression method are proposed. From the simulation result for 3,000 cycles based on the proposed model, it is found that the accuracy of the degradation prediction model is appropriate since the actual measurement values of deterioration index and the simulation results from proposed models are nearly identical, and the proposed deterioration prediction model is calculated as approximately 2,975 cycles compared to the 3,000 cycles measurement.