Article
Chemistry, Physical
Jinpeng Tian, Rui Xiong, Weixiang Shen, Fengchun Sun
Summary: The proposed method in this paper utilizes offline OCV test results to estimate aging diagnosis of lithium ion batteries at an electrode level, achieving fast diagnosis. The estimated aging parameters are close to the results obtained by offline tests, enabling reconstruction of OCV-Q curves for battery capacity estimation with high accuracy. The influence of voltage ranges on estimation results is also discussed in the study.
ENERGY STORAGE MATERIALS
(2021)
Article
Chemistry, Physical
Ming-Ying Zhou, Jian-Bang Zhang, Chi-Jyun Ko, Kuo-Ching Chen
Summary: In this study, a time-saving approach for measuring the open-circuit voltage (OCV) of a battery is proposed. By using a simplified first-order RC circuit model, the OCV at each state of charge (SOC) can be computed without the need for complete voltage relaxation information. Experimental results demonstrate that this approach significantly reduces the measurement time (usually less than 6 minutes) while maintaining high accuracy (usually less than 3 mV) compared to traditional methods.
JOURNAL OF POWER SOURCES
(2023)
Article
Electrochemistry
Ujwal N. Jibhkate, Uday B. Mujumdar
Summary: This paper proposes a simple and low complexity open-circuit voltage model for estimating the State of Charge (SOC) of a battery. To improve accuracy, the model is modified using a two-degree polynomial function dependent on the remaining useful life (RUL). Experimental results show that the proposed model efficiently limits the error below a certain threshold for the entire SOC range.
ELECTROCHIMICA ACTA
(2022)
Article
Energy & Fuels
Zhong Ren, Changqing Du, Zhongyi Wu, Jianbo Shao, Wenjun Deng
Summary: This paper investigates the effects of different current rates on OCV tests and their impact on SoC estimation algorithms. The results show that the OCV-SoC curve obtained from the 0.5C incremental OCV test performs best at 25 degrees C and 45 degrees C, while the 0.2C incremental OCV test performs best at 0 degrees C. Additionally, a 3-hour relaxation time is optimal at higher temperatures, while a 4-hour relaxation time is recommended at 0 degrees C.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2021)
Article
Chemistry, Physical
Hao Cui, Dongsheng Ren, Mengchao Yi, Sixuan Hou, Kai Yang, Hongmei Liang, Xuning Feng, Xuebing Han, Youzhi Song, Li Wang, Xiangming He
Summary: The wetting process is crucial in battery production efficiency and quality, especially for large-format or high-energy density lithium-ion batteries. This study proposes a method for in-situ monitoring of the open circuit voltage during electrolyte filling, providing valuable information about the process.
Article
Computer Science, Information Systems
Yimin Qian, Jian Zheng, Kai Ding, Hui Zhang, Qiao Chen, Bei Wang, Yi Wang, Zengrui Huang
Summary: This paper proposes an effective method for fast measurement of battery open circuit voltage using a relaxation model and genetic algorithm for parameter optimization. The method can accurately estimate the battery's open circuit voltage in a short time and is effective under different conditions.
Article
Energy & Fuels
Gaoqi Lian, Min Ye, Qiao Wang, Meng Wei, Yuchuan Ma
Summary: To achieve a high-robustness state of charge (SOC) estimation for lithium-ion batteries under different ambient temperatures with noise effects, a noise-immune SOC estimation method is proposed. The method includes establishing a high-precision fitting model of the open-circuit voltage based on the moving window principle, developing a new dynamic model parameter identification method using the Multi-Verse Optimizer, and improving the unscented Kalman filter based on adaptive theory and matrix diagonalization theory. The proposed method is validated to maintain stability and accuracy in SOC estimation at different temperatures and under varying working conditions.
JOURNAL OF ENERGY STORAGE
(2023)
Article
Thermodynamics
Limei Wang, Jingjing Sun, Yingfeng Cai, Yubo Lian, Mengjie Jin, Xiuliang Zhao, Ruochen Wang, Long Chen, Jun Chen
Summary: This paper proposes a method to construct a complete OCV-SOC curve at different temperatures based on cloud data. It also establishes an OCV-SOC model suitable for different temperatures using an improved electrode potential model. Additionally, a method to construct a complete OCV-SOC curve from the charge segment based on the thermodynamic ideal material characteristics is proposed.
Article
Chemistry, Analytical
Junfu Li, Ming Zhao, Changsong Dai, Zhenbo Wang, Michael Pecht
Summary: A mathematical method for acquiring open-circuit potential curves of lithium-ion batteries was developed, using known open-circuit potentials of positive and whole-cell voltages at low discharge rates. The method utilizes hyperbolic tangent and exponential functions to describe the negative electrode's open-circuit potential against different lithiation states, with unknown coefficients identified using least squares fitting. Testing on five types of batteries demonstrated the accuracy and robustness of the method.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2021)
Article
Engineering, Chemical
Huixin Tian, Jianhua Chen
Summary: Accurate estimation of SOC is crucial for vehicle management systems. This paper introduces an attention-based CONV-LSTM module for SOC prediction, based on CNN and LSTM networks, which shows promising results in experiments.
Article
Energy & Fuels
Yizhao Gao, Ziqiang Sun, Dong Zhang, Dapai Shi, Xi Zhang
Summary: This paper proposes a method to establish the relationship between electrode open-circuit potential (OCP) and stoichiometry, and optimizes OCP and hysteresis factor for estimating full-cell OCP. Experimental results show that the proposed method achieves accurate voltage prediction for the battery.
Article
Energy & Fuels
Rui Xiong, Yanzhou Duan, Kaixuan Zhang, Da Lin, Jinpeng Tian, Cheng Chen
Summary: Accurate estimation of state-of-charge (SOC) is crucial for efficient and safe battery applications. However, existing SOC estimation methods fail for LiFePO4 batteries due to their flat voltage-SOC relationship. To address this, an adaptive algorithm is used to identify open-circuit voltage (OCV) and update parameters for the extended Kalman filter based on different OCV ranges. Additional filtering methods improve the stability of estimation. Experimental validation shows high accuracy and stability with a maximum absolute error of <2%. Real battery data further confirms the viability of the proposed method, laying a foundation for reliable LiFePO4 battery management in electric vehicles.
Article
Energy & Fuels
Lili Xia, Shunli Wang, Chunmei Yu, Yongcun Fan, Bowen Li, YanXin Xie
Summary: Accurate prediction of remaining mileage for electric vehicles is still a challenge. This paper proposes a novel fusion equivalent-circuit model of lithium-ion batteries considering the influence of temperature to obtain a high precision mathematical description and state parameters. An adaptive noise correction-dual extended Kalman filtering algorithm is adopted for the estimation of state-of-energy and state-of-charge, solving the noise influence of Kalman filtering. Experimental results show that the proposed method achieves estimation errors within 1.83% and 1.92% at different working temperatures and conditions, proving the efficiency of the co-estimation method.
JOURNAL OF ENERGY STORAGE
(2022)
Article
Energy & Fuels
Haisheng Guo, Xudong Han, Run Yang, Jinjin Shi
Summary: This paper proposes a multi-scale estimation algorithm that combines fractional order adaptive extended Kalman filter and variable forgetting factor recursive least square to solve the problem of SoC estimation in lithium-ion battery management system. Experimental results show that the proposed method achieves high accuracy and robustness.
JOURNAL OF ENERGY STORAGE
(2022)
Article
Thermodynamics
E. Jiaqiang, Bin Zhang, Yan Zeng, Ming Wen, Kexiang Wei, Zhonghua Huang, Jingwei Chen, Hao Zhu, Yuanwang Deng
Summary: This paper investigates the essence of inconsistency in lithium-ion batteries as State-Of-Charge (SOC) inconsistency, proposing a method to describe battery inconsistency using SOC disparity and studying the equalization control strategy. Through simulations and experiments, it is shown that active equalization significantly improves cell inconsistency and enhances energy utilization in the battery pack during charging and discharging processes. The proposed SOC estimation method meets accuracy requirements, and the equalization strategies effectively minimize SOC and voltage disparities among battery cells.