Polysulfide Flow Batteries Enabled by Percolating Nanoscale Conductor Networks.

Nano letters

PubMedID: 24597525

Fan FY, Woodford WH, Li Z, Baram N, Smith KC, Helal A, McKinley GH, Carter WC, Chiang YM. Polysulfide Flow Batteries Enabled by Percolating Nanoscale Conductor Networks. Nano Lett. 2014;.
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.