Sulfur-containing C2H2O8S2 molecules as an overall-functional electrolyte additive for high-voltage LiNi0.5Co0.2Mn0.3O2/graphite batteries with enhanced performance

The optimization of electrode-electrolyte interfacial properties plays a key role in the stable operation of high-energy density lithium-ion batteries (LIBs) over a wide temperature range. In this work, a functional electrolyte using dihydro-1,3,2-dioxathiolo [1,3,2]dioxathiole-2,2,5,5-tetraoxide (D-DTD) molecules as an overall-functional additive is designed and used to enhance the comprehensive performance of LiNi0.5Co0.2Mn0.3O2/graphite batteries under extreme conditions, namely, a high 4.4 V working potential and a wide temperature range of −30 °C–60 °C. The batteries with D-DTD exhibit stable coulombic efficiency, enhanced cycling stability, and superior rate performance. Specifically, the batteries with D-DTD retain 89.1% of their original reversible capacities after 150 cycles at room temperature, while only 55.4% and 84.0% capacity retentions are obtained from the batteries without additive and with 1,3,2-dioxathiolane-2,2-dioxide (DTD), respectively. Interestingly, the addition of D-DTD to the baseline electrolyte promotes higher cycling retentions of 77.2% (45 °C) and 92.5% (−10 °C) after 100 cycles in comparison to 14.7% and 82.1% with DTD-added electrolyte, respectively. It is demonstrated that D-DTD can participate in the construction of interfacial films on both cathode and anode, which contributes to stabilizing the electrode-electrolyte interfaces and reducing parasitic interfacial reactions of LIBs.