A full battery system of pre-lithiated phosphorus/sulfurized pyrolyzed poly(acrylonitrile) with an effective electrolyte and improved safety

Abstract

Excessive stress has deteriorated the energy crisis and environmental problems; therefore, introducing a new rechargeable battery system for large-scale energy storage and electric vehicles (EVs) has become a major concern. Recently, phosphorus (P) anode as one of the promising candidates for fast-charging lithium-ion batteries (LIBs) has gained significant attention for safe EVs due to its low cost, high energy density and relatively high lithiation voltage (ca. 0.7 V vs. Li⁺/Li). However, its flammability, unavoidable side reactions with the electrolyte and large volumetric variation (∼300%) during cycling limit its large-scale employment. Herein, a localized high-concentration flame-retardant LiFSI-based electrolyte has been reported to simultaneously construct an elastic and robust LiF-rich solid electrolyte interface (SEI) both at the P anode and sulfur cathode. Thus, a new Li₃P-sulfur full battery system based on the pre-lithiated P anode and the sulfurized pyrolyzed poly(acrylonitrile) cathode was built, delivering a high capacity retention of 97.1% after 600 cycles at 1 A g⁻¹. This battery system avoids some fatal flaws of the Li–S battery, including Li dendrite formation and thermal instability. This work provides an alternative direction to obtain green and long-life batteries for commercial availability.