Powder XRD patterns of the SbxBi1-x alloys in the as-prepared and annealed states are shown in Figure . The unlithiated starting alloys were prepared via melt spinning followed by thermal annealing. The cooling rate during melt spinning is insufficient to cross the liquidus-solidus gap vertically and produce a single-phase material, which is why a subsequent annealing step is required to form a single-phase compound. As illustrated on the right-hand side in Figure , all XRD patterns are shifted towards lower angles, i.e. larger d-spacing, as the Bi content is increased, which is expected based on the larger atomic radius (148 pm (Bi) vs 139 pm (Sb)) of this element. Although thermodynamic calculations point to the possible existence of a miscibility gap below 140 °C, experimental evidence for this gap is difficult to interrogate experimentally as solid-state diffusion is very slow at these low temperatures. Although the samples described here ere no q enched in an a af er he annealing s ep, here is no evidence for phase separation and complete solid solubility appears to be achieved. As an additional illustration, the XRD patterns in Figure