Dual-additive enabled inorganic-rich solid electrolyte interphase for high-rate lithium negative electrodes

Abstract Constructing a robust, highly conductive solid electrolyte interphase is the key to unlock the high-rate potential of lithium negative electrodes for broad applications. Here we propose a simple yet effective strategy, by introducing a sulfur-containing compound and LiNO 3 as dual additives into a conventional carbonate electrolyte. As an example, 3-sulfolene is found to enhance the dissolution of LiNO 3 , and it works with NO 3 − to regulate the Li + -solvation structure and facilitate the formation of a robust while uniform solid electrolyte interphase rich in Li 3 N/Li 2 S/Li 2 O inorganics, enabling rapid Li + transfer and high interfacial stability. Consequently, Li | |LiFePO 4 cells achieve 81.7% capacity retention after 6,000 cycles at 80 C, while Li | |LiNi 0.8 Co 0.1 Mn 0.1 O 2 cells maintain 81.3% capacity after 500 cycles at 10 C. Moreover, two pouch cells with specific energy exceeding 500 Wh kg −1 (calculated based on total mass of the pouch cells) retain 92.1% and 91.8% of initial capacities after 143 and 149 cycles (charged at 0.1 C and discharged at 0.3 C), respectively. This work provides a general dual-additive strategy to promote the formation of an inorganic-rich solid electrolyte interphase for high-rate lithium negative electrodes.