Engineering zinc slurry anodes for high-performance primary alkaline batteries

The anode in Zn alkaline batteries is complex, comprised of zinc powder, gelled electrolyte, and additives, including surfactants. Optimizing the performance of these anodes means improving material utilization and suppressing corrosion of the electroactive zinc, which translates in real cells to higher energy density and longer shelf life. A challenge with optimizing these anodes has been in isolating the performance of the zinc slurry from the rest of the cell components in traditional, high-throughput cell-build studies. In this work, we use a combination of ex-situ and in-situ platforms to understand the effects of Zn content, KOH weight percent in the electrolyte, surfactant type and surfactant level on anode behavior. This is done by using electrochemical techniques including electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR), potentiodynamic polarization (PDP), and constant current (galvanostatic) discharge (CCD). The results of these experiments were combined with a systematic design of experiments (DoE) matrix, allowing for optimized slurries to be realized and tested in-situ in commercially representative cells. This work can aid in intelligently designing zinc slurries for deployment in commercial products.