Electrode precursor composition

An electrode precursor composition or an electrode for an alkali metal ion secondary cell may comprise: a polymer electrolyte gel matrix phase and a dispersed phase. The dispersed phase may comprise an electrochemically active material, e.g. a lithium transition metal oxide, and a conductive additive. The conductive additive may comprise a tubular carbon material, e.g. multi-walled carbon nanotubes, as a majority component. The conductive additive preferably contains substantially no conductive carbonaceous material other than the tubular carbon material. An electrochemical secondary cell or energy storage device may comprise the electrode. A method of producing an electrode may comprise mixing a polymer, electrolyte, electrochemically active material and conductive additive comprising a majority of tubular carbon component to form an electrode precursor composition and then processing to form an electrode film.