Past exam of the MPhil in micro- and nanotechnology enterprise course of the University of Cambridge / 2023 / Paper 1 / Section B / 11 / i / Solution

On discharge, lithium is oxidized at the negative electrode:At the positive electrode, carbon monofluoride is reduced:The net conversion reaction is thereforeFor general ${\mathrm{CF}}_x$, replace Li, lithium ions, electrons and LiF by $x$ equivalents per carbon atom. The carbon–fluorine bonds are consumed in forming different solid phases, rather than lithium simply intercalating reversibly into an unchanged host.