Prediction of State-of-Health for Nickel-Metal Hydride Batteries by a Curve Model Based on Charge-Discharge Tests

Energies

Huan Yang¹  Yubing Qiu¹  Xingpeng Guo¹ 

[1] School of Chemistry and Chemical Engineering, Huazhong University of Science and Technology, Wuhan 430074, China;

关键词: nickel-metal hydride (Ni-MH) battery;    state-of-health (SOH);    curve fitting;    nonlinear least-squares method;    prediction;   

DOI  :  10.3390/en81112322

来源: mdpi

【 摘 要 】

Based on charge-discharge cycle tests for commercial nickel-metal hydride (Ni-MH) batteries, a nonlinear relationship is found between the discharging capacity (C_discharge, Ah) and the voltage changes in 1 s occurring at the start of the charging process (ΔV_charge, mV). This nonlinear relationship between C_discharge and ΔV_charge is described with a curve equation, which can be determined using a nonlinear least-squares method. Based on the curve equation, a curve model for the state-of-health (SOH) prediction is constructed without battery models and cycle numbers. The validity of the curve model is verified using (C_discharge, ΔV_charge) data groups obtained from the charge-discharge cycle tests at different rates. The results indicate that the curve model can be effectively applied to predict the SOH of the Ni-MH batteries and the best prediction root-mean-square error (RMSE) can reach upto 1.2%. Further research is needed to confirm the application of this empirical curve model in practical fields.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.