Nanostructured Composite Foils Produced Via Accumulative Roll Bonding as Lithium-Ion Battery Anodes

In this work, we introduce a new nanostructured composite foil (NCF) alloying anode framework for high-capacity anode materials for lithium-ion batteries. These materials are manufactured with an accumulative roll-bonding process, a simple route for the generation of hierarchical nanostructures. The model Sn/Cu NCF system provides volumetric capacities between 1000 and 1720 mA h cm-3, equating to a projected 20-50% increase in cell-level volumetric energy density. The initial electrochemical cycle was associated with an efficient formation process (88-92%) that drastically increased transport kinetics, allowing for rapid lithiation (>8 mA cm-2) on subsequent cycles. The introduction of a multilayered inactive copper matrix successfully eliminated loss of the active material as a degradation mechanism, while loss of lithium-inventory limited long-term cyclability in lithium-limited environments. Further development of this framework to mitigate loss of lithium inventory may provide a promising route toward the production of high-energy battery materials.