No abstract

The electrochemical performances of LiTi 2 (PS 4 ) 3 (LTPS) with a 75Li 2 S-25P 2 S 5 glass-ceramic solid electrolyte (SE) are investigated. In spite of irreversibility of structural changes, LTPS exhibits a high first discharge capacity of 455 mAh g −1 with good cycling retention of 76% at the 25th cycle between 1.5-3.5 V at 50 mA g −1 at 30 • C. In sharp contrast, LTPS with a liquid electrolyte (LE) in a conventional cell loses half of its initial capacity after only 14 cycles. The much poorer performance of LTPS in the LE compared to that in the SE is believed to be associated with dissolution of LTPS into the LE. The results highlight the prospects of exploring electrode materials that are compatible with SEs for all-solid-state batteries.

The performance of nanocomposite electrodes prepared by controlled ball-milling of TiS2 and a Li2S–P2S5 solid electrolyte (SE) for all-solid-state lithium batteries is investigated, focusing on the evolution of the microstructure. Compared to the manually mixed electrodes, the ball-milled electrodes exhibit abnormally increased first-charge capacities of 416 mA h g−1 and 837 mA h g−1 in the voltage ranges 1.5–3.0 V and 1.0–3.0 V, respectively, at 50 mA g−1 and 30°C. The ball-milled electrodes also show excellent capacity retention of 95% in the 1.5–3.0 V range after 60 cycles as compared to the manually mixed electrodes. More importantly, a variety of characterization techniques show that the origin of the extra Li+ storage is associated with an amorphous Li–Ti–P–S phase formed during the controlled ball-milling process.