Layered/Olivine Composite Structure-Induced Stable Gradient Interfacial Chemistry toward High-Temperature Lithium-Ion Batteries
Shaoze Tian, Shiqi Liu, Haozhe Du, Runke Zhang, Yulong Wang, Peipei Ding, Jian Wang, Yuming Li, Shu Zhao, Xianwei Guo, Haijun Yu
Abstract
The state-of-the-art layered oxide as the cathode material for lithium-ion batteries has attracted wide attention; however, harsh operations of high-energy and high-safety energy-storage technology at high temperature is challenging owing to the aggravated structural instability and parasitic reactions at the cathodes. Herein, the layered/olivine composite structure architecture is designed at the grain surface to govern constant electrochemistry in a harsh environment, and a gradient LiF interlayer is developed onto the cathodes to suppress the interfacial degradation. By a combination of interfacial-sensitive characterizations and theoretical analysis at the cathode/interface, the formation mechanism of this special interphase induced by the composite structure cathode is revealed. The composite structure cathode could deliver an excellent high-temperature cycling stability with 90.8% retention for 300 cycles in the half cell and 95.6% retention for 1000 cycles in the pouch cell and simultaneously enhances ∼51% of the thermal stability, which broadens the approaches for developing high-stable cathodes that work in extreme environments.