A Multifunctional Electrolyte Additive With Solvation Structure Regulation and Electrode/Electrolyte Interface Manipulation Enabling High-Performance Li-Ion Batteries in Wide Temperature Range

Improving the tolerance of Li-ion batteries (LIBs) to extreme temperatures and climates worldwide is vital to their global uptake. However, LIBs call for more strict requirements for the key components when operated in a wide temperature range, especially synchronously desirable interfacial kinetics and thermal stability. Here, a novel multifunctional electrolyte additive, N-tert-butyl-2-thiophenesulfonamide (NTSA), to fabricate stable LIBs under wide-temperature conditions, is reported. The Li-ion solvation structure in the electrolyte is regulated and involves less coordinated solvents (particularly fluoroethylene carbonate), leading to superior Li+ transportation. The effective NTSA additive is preferentially decomposed to form a uniform electrode/electrolyte interface with abundant multiphase inorganic Li-F, Li3N, and Li-S species simultaneously on the cathode and anode surface. The resulting inorganic-rich interface can not only boost the interfacial Li-ion transfer kinetics at low temperatures but also protect the active material and enhance the thermal stability of the interface and LIB devices at high temperatures. By adopting the NTSA-containing electrolyte, LiCoO2||omega-Li3V2O5 LIBs can be stably cycled in a wide temperature range between -30 degrees C and 80 degrees C, delivering a high capacity of approximate to 100.1 mAh g(-1) (0.2 A g(-1)) at -20 degrees C and high capacity retention of 94.5% after 200 cycles (0.5 A g(-1)) at 55 degrees C.

Automated summary

A novel multifunctional electrolyte additive, NTSA, is reported to fabricate stable Li-ion batteries under wide-temperature conditions. The NTSA additive regulates the solvation structure of Li-ion in the electrolyte, forming a uniform inorganic-rich electrode/electrolyte interface and enhancing interfacial kinetics at low temperatures and thermal stability at high temperatures. LiCoO2||omega-Li3V2O5 LIBs with NTSA-containing electrolyte exhibit stable cycling in a wide temperature range and deliver high capacity and capacity retention.