Degradation diagnosis of lithium-ion batteries with a LiNi0.5Co0.2Mn0.3O2 and LiMn2O4 blended cathode using dV/dQ curve analysis

JOURNAL OF POWER SOURCES

卷:390

Article

Ando, Keisuke¹  Matsuda, Tomoyuki¹  Imamura, Daichi¹ 

[1] Japan Automobile Res Inst, E Mobil Res Div, 2530 Karima, Ibaraki 3050822, Japan

关键词: Blended cathode;    dV/dQ curve analysis;    Degradation mechanism;    Lithium ion battery;    Nondestructive analysis;   

DOI  :  10.1016/j.jpowsour.2018.04.043

来源: Elsevier

【 摘 要 】

Understanding the degradation factors (cathode and anode degradation and solid electrolyte interface (SEI) formation) of lithium-ion batteries (LIBs) with a blended cathode is necessary to improve their durability because battery drive vehicles often use LIBs with a blended cathode due to advantages of power and cost. We developed a dV/dQ curve analysis adapted for through a dQ/dV curve analysis to elucidate the relations between cycle test conditions and degradation factors. To compare said factors, cycle tests were conducted under different conditions: one charge/discharge rate (C/3), two state-of-charge (SoC) ranges (100%-0% and 100%-70%), and three temperatures (0 degrees C, 25 degrees C, and 45 degrees C). We confirmed that there are clear differences in the degree of contribution of each degradation factor depending on conditions. For instance, at 0 degrees C, although the capacity reduction rate was almost the same regardless of the SoC range, the degradation mechanisms were different, i.e., the cathode degradation and the SEI formation occurred at the same time, resulting in the reduced capacity for the 100%-0% SoC range, while capacity reduction was mainly due to SEI formation for the 100%-70% SoC range.

【 授权许可】

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