Electrochemical Properties of All-solid-state Lithium Batteries with Amorphous FeS<i>_x</i>-based Composite Positive Electrodes Prepared via Mechanochemistry

Abstract

Iron sulfide (FeS x) composite positive electrodes were prepared mechanochemistry and applied to all-solid-state lithium cells. The prepared composites, consisting of Fe, S, Li 3 PS 4 solid electrolyte (SE), and vapor-growth carbon fiber (VGCF), were in amorphous state after ball milling for 10 h. An all-solid-state cell with an amorphous Fe-S-SE-VGCF composite as the positive electrode exhibits a high reversible capacity of 420 mAh per total weight of the composite electrode at a current density of 0.13 mA cm −2 at 25°C. The cell exhibited a capacity retention of 88% after 200 cycles at a current density of 0.64 mA cm −2 at 25°C. The all-solid-state cell using the Fe-S-SE-VGCF composite at a current density of 0.13 mA cm −2 at 100°C exhibited a higher reversible capacity of 550 mAh g −1. The Fe-S-SE-VGCF composite is thus a promising positive electrode material, with high capacity and good cycle performance for all-solid-state lithium secondary batteries.

Dense All‐Electrochem‐Active Electrodes for All‐Solid‐State Lithium Batteries

“…Following careful screening, a series of conductive transition metal sulfides caught our attention. [ 25–28 ] In previous works, pure amorphous transition metal sulfide cathodes were used as the electrode ASSLBs. [ 29–31 ] However, their electronic conductivity (≈10 −3 S cm −1 ) is four orders of magnitude lower than carbon (≈10 S cm −1 ), [ 32 ] and their ionic conductivity is not particularly stable during the charge–discharge process.…”

Recent progress and perspectives on cation disordered rock-salt material for advanced Li-ion batteries

“…It is also possible to synthesize solid electrolytes using the mechanical ball milling method. 150 Therefore, we can apply the mechanical ball milling method to the material synthesis process in sodium-ion batteries. The works of Yabuuchi on DRX structured cathode materials for Na-ion batteries are based on the summary of the above series of studies.…”

High-Packing-Density Electrodes by Self-forming Ion Conduction Pathway During Charge Process for All-Solid-State Lithium Ion Batteries

“…All-solid-state lithium-ion batteries using sulfide solid electrolytes (SEs) have the advantages of high safety due to the absence of liquid leakage and the ability to fabricate batteries in a bipolar stacked structure, which reduces the amount of extra components. − Several oxides and sulfides have been studied as cathode active materials for all-solid-state lithium-ion secondary batteries. − Among them, transition metal sulfides, such as NiS, S–FeS 2 , Co 3 S 4 , S–VS 2 , have attracted increasing attention as cathode materials because of their high capacity by using sulfur redox and low reactivity with sulfide SEs. − In addition, these cathode materials present higher electronic conductivity than sulfur and Li 2 S; moreover, they do not require a large amount of carbon as conductive material for composite electrodes, which results in a high weight energy density.…”