Enhanced Whale Optimization Algorithm with Wavelet Decomposition for Lithium Battery Health Estimation in Deep Extreme Learning Machines

Abstract

Lithium battery health state estimation can help optimize battery usage and management strategies. In response to the challenges faced by traditional battery management systems in accurately estimating the State of Health of lithium-ion batteries and addressing issues such as capacity recovery and noise interference, this paper proposes a method based on wavelet decomposition and an improved whale optimization algorithm optimized deep extreme learning machine for estimating the SOH of lithium-ion batteries. Firstly, the lithium-ion battery capacity degradation sequence is extracted, and the wavelet decomposition method is used to decompose the battery capacity into global and local degradation trends. Next, the non-linear convergence factor and the whale optimization algorithm with adaptive weights are employed to optimize the deep extreme learning machine for predicting each trend component. Finally, the prediction results are effectively integrated to obtain the lithium-ion battery SOH. This experimental method is validated using NASA and CALCE datasets, and the results indicate that the root mean square error and mean absolute percentage error are both below 0.95%, with relative accuracy and absolute correlation coefficients exceeding 98%. This demonstrates the method’s excellent accuracy and robustness.

Data-Driven Semi-Empirical Model Approximation Method for Capacity Degradation of Retired Lithium-Ion Battery Considering SOC Range

“…Considering that f (s, x, t) is a nonlinear function, a set of nonlinear equations will be obtained when solving the partial derivative of the undetermined parameter vector based on Equation (21), so the iterative method is used for the solution [40].…”

“…[8]. Most of the existing studies on the capacity degradation of lithium batteries are based on the accelerated aging test data, which can be mainly divided into three types: electrochemical mechanism model [9][10][11][12][13], empirical model [14][15][16][17][18][19][20], and data-driven model [21][22][23][24]. The method based on the electrochemical mechanism model involves the physical and chemical process of the battery and then researches the law of the influence of the aging process on state variables.…”