Electrochemical performances of the Li2S-P2S5 solid electrolyte (SE)-acetylene black (AB) composite electrode materials were examined in all-solid-state lithium secondary batteries. The xLi(2)S center dot(100 - x)P2S5 (x = 80, 87.5, 90, 95 and 100 mol%) SEs with the addition of AB were partially used as an active material with lithium source in all-solid-state cells. The cell using the 80Li(2)S center dot 20P(2)S(5) SE-AB composite electrode exhibited the largest charge capacity of 240 mAh g(-1) (normalized by the weight of 80Li(2)S center dot 20P(2)S(5)) in the xLi(2)S-(100 - x)P2S5 SEs. The relation between the obtained charge capacities and the electrical conductivities of the components of the composite electrodes was investigated. (C) 2013 Elsevier B.V. All rights reserved.