A comparative study on the reactivity of charged Ni-rich and Ni-poor positive electrodes with electrolyte at elevated temperatures using accelerating rate calorimetry

• 作者: Dongxu Ouyang Yulong Liu Ines Hamam Jian Wang Jeff Dahn
• 来源期刊: 能源化学
• 年，卷（期）: 2021,（9）
• 页码范围: 523-530
• 页数: 8页
• 语种: 英文

摘要

The reactivity between charged Li(Li0.115Mn0.529Ni0.339Al0.017)O2(Li-rich),single crystal Li(Ni0.8Mn0.1Co0.1)O2(SC-NMC811),LiFePO4(LFP)and LiMn0.8Fe0.2PO4(LMFP)positive electrodes at different states of charge(SOCs)and traditional carbonate-based electrolyte at elevated temperatures is systematically studied using accelerating rate calorimetry(ARC).The results show that the SOC greatly affects the ther-mal stability of the Li-rich and SC-NMC811 when traditional carbonate-based electrolyte is used.Although an increase in the SOC increases the energy density of lithium-ion cells,it also increases the reactivity between charged Li-rich and SC-NMC811 samples with electrolyte at elevated temperatures.In comparison with SC-NMC811,the Li-rich samples are much more stable at elevated temperatures,and the latter have higher specific capacity.SC-NMC811 samples are less reactive than traditional poly-crystalline NMC811.Both LFP and LMFP samples show excellent thermal stability at elevated tempera-tures.The substitution of Fe by Mn in the olivine series positive materials does not impact the reactivity with electrolyte.