In practical applications, the batteries are usually subjecting to short-term high-temperature storage (e.g., 80 °C for several days), which is quite different from long-term storage with temperature lower than 60 °C. Herein, the effect of such a short-term high-temperature storage on the performance of LiNi_0.5Co_0.2Mn_0.3O₂/graphite battery under normal cycling (under 1C at 25 °C) is studied by electrochemical characterizations and post-mortem analysis. Due to the thickened Solid-Electrolyte-Interface (SEI) film on the stored anode, the loss of active lithium significantly increases after cycling and leads to increased cathode state of charge (SOC) offset. On the other hand, the thickened Cathode-Electrolyte-Interface (CEI) layer on stored cathode consists of more organic contents due to particle cracking. Such interface degradations hinder lithium ion diffusion, causing increased polarization, SOC offset, and reduced inherent performance of the electrodes. By quantificationally analyzing the degradation factors, it is revealed that the polarization related to interfaces is the dominating factors for battery degradation, and the cathode decay rate is distinctly expedited after short-term high-temperature storage. Additionally, the decreased thermal stability of electrode materials is observed by differential scanning calorimeter (DSC) measurements. In all, the short-term high-temperature storage accelerates the battery aging during normal cycling and reduces the battery safety.

在实际应用中，电池通常要进行短期高温存储（例如80°C数天），这与温度低于60°C的长期存储完全不同。在此，这种短期高温保存对LiNi _0.5 Co _0.2 Mn _0.3 O _{2的性能的影响}通过电化学表征和验尸分析研究了在正常循环（25°C下在1C下）下的/石墨电池。由于存储的阳极上的固体电解质界面（SEI）膜变厚，所以活性锂的损失在循环后会显着增加，并导致阴极电荷状态（SOC）偏移增加。另一方面，由于颗粒开裂，在存储的阴极上增厚的阴极-电解质界面（CEI）层包含更多的有机成分。这样的界面劣化阻碍了锂离子扩散，导致极化增加，SOC偏移和电极的固有性能降低。通过对退化因素进行定量分析，发现与界面有关的极化是电池退化的主要因素，短期高温保存后阴极衰变速率明显加快。另外，通过差示扫描量热仪（DSC）测量观察到电极材料的热稳定性降低。总之，短期高温存储会加速正常循环期间的电池老化，并降低电池安全性。