Superwettable High-Voltage LiCoO 2 for Low-Temperature Lithium Ion Batteries

Abstract

Lithium-ion batteries with both low-temperature (low- T ) adaptability and high energy density demand advanced cathodes. However, state-of-the-art high-voltage (high- V ) cathodes still suffer insufficient performance at low T, which originates from the poor cathode–electrolyte interface compatibility. Herein, we developed a shallow surface Zr-doped and Li + conductive Li 2 Zr(PO 4 ) 2 (LZPO) interspersed massage-ball-like LiCoO 2 (LZPO-LCO). The surface-interspersed LZPO can induce an electrolyte superwettability of LZPO-LCO, which helps to form a high-quality cathode–electrolyte interphase with strong stability and low interface resistance. Without changing electrolyte, even at a low T of −25 °C and a high V of 4.6 V, LZPO-LCO shows an ultrahigh capacity of ∼200 mAh g –1 at 0.2C and 137 mAh g –1 at 5C, maintaining 94% capacity after 100 cycles with an average Coulombic efficiency of 99.9%. Besides, the fabricated full cells deliver a high energy density of ∼340 Wh kg –1 and maintain 92% capacity after 200 cycles at −25 °C. This work provides a significant leap forward for high-performance low- T cathodes.