Optimization of physicochemical characteristics of a lithium anode interface for high-efficiency cycling: an effect of electrolyte temperature

Precycling of lithium (Li) metal on a nickel substrate at a low-temperature (-20 degreesC) in propylene carbonate (PC) mixed with dimethyl carbonate ( DMC) and Li hexafluorophosphate (LiPF6) (LiPF6-PC/DMC) enhanced Li cyclcabi lity in the subsequent cycles at a room temperature (25 degreesC). In LiPF6 -PC/DMC, not only the low-temperature precycling in the initial 10 cycles w as effective in the improvement of Li cycle life but also the first low-tem perature Li deposition followed by room temperature cycling enhanced the: L i cycle life. Such a precycling effect was observed with various current de nsities at the initial Li deposition and the subsequent cycling. When the c urrent density of the cycling was high, improved cycling efficiency was obs erved and the efficiency of the Li electrode undergoing the precycling was dose to that at a constant temperature of -20 degreesC. (C) 2001 Elsevier S cience B.V. All rights reserved.