Iron-based sulfides have been deemed as an appealing anode material for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs) for their high theoretical capacity and low cost. However, their practical application is limited by drastic volume expansion during cycling and low-intrinsic electronic conductivity.
Iron is a productive element in the crust, and its oxides, sulfides, fluorides, and oxygen acid salts are extensively investigated as electrode materials for batteries. In view of the importance of electrode materials containing iron, this review summarizes the recent achievements on various binary iron sulfides (FeS, FeS 1. Introduction
Herein, we report a highly electronegative anion oxygen-incorporated lithium iron sulfide (Li 2 FeS 2–x O x) cathode material with enhanced structural stability, intrinsic conductivity, and improved electrochemical performance.
Moreover, the research on sulfide all-solid-state batteries (ASSBs) with metal fluoride cathode is still lacking. Herein, four kinds of iron fluoride materials are applied to the sulfide all-solid-state lithium battery system for the first time to investigate the best cathode and corresponding methods.
The synthetic methods of iron sulfides are discussed. Recent progress on various binary iron sulfides' electrochemical applications is overviewed. More attention should be paid on their applications for post-lithium types of batteries. Effective utilization of energy requires the storage and conversion device with high ability.
Lithium sulfide nano-powder material holds great promise as a cathode material and prelithiation agent due to its high theoretical capacity and as an indispensable precursor for sulfide solid electrolytes. However, its industrial application is greatly impeded by problems of low purity, large particle size, and high cost.