In this paper, electrode laminae consisting of carbon fibres embedded in structural battery electrolyte are characterized with respect to their multifunctional (i.e. combined electrochemical and mechanical) performance utilizing experimental and numerical techniques. The Effects of electrode lamina thickness on electrochemical performance are measured. Li-insertion induced longitudinal expansion of carbon fibre electrodes is measured in situ during electrochemical cycling. A previously developed coupled electro-chemo-mechanical finite element model is validated based on experimental data. We expect that the utilized computational framework and experimental data open a route to develop high-performing, both mechanically and electrochemically, carbon fibre based battery electrode laminae for future lightweight structural components with energy storage ability.