A new approach to flow battery design is demonstrated wherein diffusion-limited aggregation of nanoscale conductor particles at ∼1 vol % concentration is used to impart mixed electronic-ionic conductivity to redox solutions, forming flow electrodes with embedded current collector networks that self-heal after shear. Lithium polysulfide flow cathodes of this architecture exhibit electrochemical activity that is distributed throughout the volume of flow electrodes rather than being confined to surfaces of stationary current collectors. The nanoscale network architecture enables cycling of polysulfide solutions deep into precipitation regimes that historically have shown poor capacity utilization and reversibility and may thereby enable new flow battery designs of higher energy density and lower system cost. Lithium polysulfide half-flow cells operating in both continuous and intermittent flow mode are demonstrated for the first time.

Rapid adoption of lithium‐ion batteries for electronics and electric vehicles requires cost‐effective and efficient recycling of battery components especially the valuable cathode active materials. The direct recycling method transforms end‐of‐life (EOL) cathode materials into battery grade materials with minimal energy consumption and least environmental disruption. In direct recycling, the relithiation step to restore the lithium stoichiometry of the cathode materials is critical. In this work, a novel electrochemical relithiation approach in an aqueous electrolyte followed by a heat treatment for recycling cathode materials in EOL lithium‐ion batteries is demonstrated and analyzed. Using LiCoO₂ as an example, it is shown that the recycled LiCoO₂ materials show equivalent crystal structure, morphology, and electrochemical performance to the commercial LiCoO₂.