State of health diagnosis and estimation of power lithium-ion batteries based on open circuit voltage characteristic
JIANG Jiuchun
MA Zeyu
LI Xue
ZHANG Caiping
ZHANG Weige
Abstract：Due to the complex configuration for battery system and demanding and uncertain oper-ation conditions,it is still very challenging to understand battery aging process and related degra-dation mechanisms.In order to ensure the efficient,reliable and safe operation of the battery sys-tem,effective diagnosis and estimation of the battery state of health (SOH)is essential for the accurate battery management and control.Here the changes of open circuit voltage (OCV)char-acteristic is analyzed to establish a quantitative relationship between battery capacity fade and its degradation mechanisms,using in-situ electrochemical analysis methods,such as incremental ca-pacity analysis and differential voltage analysis.Then a more realistic and accurate diagnosis of battery SOH from the perspective of the degradation mechanism is done.And a capacity estima-tion model based on OCV is proposed for battery SOH estimation,which not only captures the electrochemical reaction characteristics at different cell aging stages but also has high accuracy and robustness.The results show that the model errors are less than 4% of the nominal capacity during the whole life span of the batteries.
Keywords：lithium-ion batterystate of healthincremental capacity analysisdifferential voltag-eanalysiscapacity estimation model
Publication Date：2016-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 92-98 )