저항 열화 기반의 배터리 팩 편차 파라미터 추출 방안 및 검출 알고리즘

초록

A large number of lithium-ion batteries are arranged in series and parallel in battery packs, such as those inelectric vehicles or energy storage systems. As battery packs age, their output power and energy density drop because ofvoltage deviation, constant and non-uniform exposure to abnormal environments, and increased contact resistance betweenbatteries; this reduces application system efficiency. Despite the balancing circuit and logic of the battery managementsystem, the output of the battery pack is concentrated in the most severely aged unit cell and the output is frequentlylimited by power derating. In this study, we implemented a cell imbalance detection algorithm and selected parametersto detect a sudden decrease in battery pack output. In addition, we propose a method to increase efficiency by applyingthe measured testing values considering the operating conditions and abnormal conditions of the battery pack.

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