Cathode interfacial engineering to enhance cycling stability of rechargeable lithium-ion batteries

Abstract

Lithium-ion batteries (LIBs) have been considered as state-of-the-art power sources. However, the long-time cycling stability, as well as thermal stability ascribed to the flammable liquid electrolyte, need much more improvement. Here, we propose a facile and scalable strategy, in which Li1.5Al0.5Ge1.5(PO4)3 (LAGP) was coated on LiCoO2 (LCO) by ball milling and sintering process to stabilize the cathode/electrolyte interphase. As a result, the cycling performance is remarkably improved. LAGP-LCO/Li cell delivers stable cycling over 1000 cycles with capacity retention of 97.8%. And high rate capability of 130.6 mAh g−1 at 5C can be achieved. Moreover, the electrolyte cannot be ignited, which dramatically avoid thermal runaway and battery failure. This investigation provides a new avenue in reinforcing the cycling stability and safety of lithium-ion batteries.