Constructing a Robust Interphase with 1,1′-Oxalyldiimidazole (ODI) Additive to Enhance the Temperature and Rate Performance of LiNi_0.8Co_0.1Mn_0.1O₂/Graphite Batteries

This work develops 1,1'-oxalyldiimidazole (ODI) as a functional electrolyte additive. This film-forming additive improves the wide range of temperature and rate performances of LiNi_0.8Co_0.1Mn_0.1O₂/graphite (NCM811) batteries. After 1200 cycles at room temperature (25 °C), the discharge capacity retention rate is 51.95% for the battery with a blank electrolyte, and it is 93.18% for that with an ODI-containing electrolyte. With 0.1% ODI, the discharge capacity retention increases from 0 to 75.89% after 500 cycles at 45 °C and increases from 48.51 to 95.54% after 300 cycles at -10 °C. In addition, the rate performance is also enhanced by the introduction of 0.1% ODI. With spectroscopic characterization, the improvement of battery electrochemical performance by ODI is supported. It is demonstrated that ODI tends to preferentially decompose on the electrodes and then participates in the construction of a stable interfacial film with low impedance, resulting in the improvement of battery performance. Not only does this work develop an imidazole-based electrolyte, but it also inspires innovative approaches to creating functional additives that can enhance battery performance.