Low temperature studies on rechargeable lithium cells

Abstract Rechargeable lithium cells using intercalating cathodes of TiS 2 , a-MoS 3 , and mixed a-MoS 3 TiS 2 were studied at temperatures from 25 °C to −40 °C. On the basis of conductivity investigations, LiAsF 6 and LiAlCl 4 electrolytes were selected for use in a binary solvent containing 24.4 mass % 4-butyrol actone in 1,2-dimethoxyethane. The Li/TiS 2 and Li/a-MoS 3 TiS2 cells cycled well at 2 mA cm −2 down to −30 °C, but at 5 mA cm −2 at these very low temperatures, cell capacities were significantly lower. At room temperatures all cells performed slightly better in 1 mol dm −3 LiAsF 6 than in 0.8 mol dm −3 LiAlCl 4 in 24 mass % 4-BL/DME. However, at temperatures below −10 °C the latter electrolyte was found to be superior.