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peer-reviewed The full text of this article will not be available in ULIR until the embargo expires on the 16/05/2020 We report the use of assemblies of SnS nanocubes as lithium‐ion battery anodes. The particles are deposited in dense, conductive thin films with high gravimetric capacity using electrophoretic deposition, negating the requirement for binders or conductive additives. Although SnS nanocube ensembles display both alloying and conversion modes, a significant benefit to capacity retention during long‐term cycling was observed by limiting the upper cutoff voltage to 1 V. In this alloying‐only regime that is more realistic for practical use, a discharge capacity of 552 mAh g−1 was delivered with a loss of only 0.08 % per cycle observed over the 400 charge/discharge cycles. We further show that the Li2S formation that occurs in the first lithiation acts as a buffer to the expansion and contraction, though crucially this effect is optimized if this species is not cycled further (>1 V). The SnS nanocube electrodes are tested in both half‐cell (HC) and full‐cell (FC) configurations and are analyzed by using ex situ SEM and EIS analysis. Finally, the electrophoretic deposition of SnS nanocubes onto a 3D textured current collector is demonstrated to increase the mass loadings

peer-reviewed Here we report an interesting observation on anode materials for lithium ion batteries that undergo combined conversion and alloying lithiation processes during cycling (CAMs). These materials are generating interest as low cost and high capacity alternatives to graphite. We find that common testing protocols (CTPs) are unsuitable for assessment of CAMs due to their distinct multi‐step lithiation characteristics. CTPs involve reporting total gravimetric capacity in a half‐cell configuration alone (opposite Li foil), without individual analysis of each process; energy density and the problems associated with wide discharge voltages are not addressed. Through isolating the individual lithiation processes of a model system (Cu2ZnSnS4), we determine that the conversion processes are highly unstable, whereas the alloying processes exhibit remarkable capacity retention. We demonstrate that inclusion of the conversion processes in cycling actually reduced full cell energy density when compared with alloying alone. This indicates that CTPs may well underestimate the stability of CAMs. It is apparent that the true advantage of CAMs lies in the synergistic combination of the capacity of the alloying portion, and the stability provided by the uncycling Li2S buffer material. Finally, we prescribe a set of testing protocols for a meaningful assessment of new CAMs.