Aluminum-based alloys are promising anode materials for metal--air systems, yet parasitic hydrogen evolution and micro-galvanic corrosion in alkaline electrolytes remain central barriers to high anodic efficiency. Motivated by prior evidence that an Al--Co--Mn composition near 20 at\% Co improves polarization resistance after thermal exposure, this work develops a process--structure--performance framework that couples heat-treatment-driven microstructural descriptors to electrochemical film properties and anode utilization. A designed heat-treatment window is applied to Al--Co--Mn alloys spanning Co and Mn contents around the reported optimum. Corrosion behavior is quantified using open-circuit stabilization, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization in \SI{3}{M} alkaline electrolyte, while functional anode metrics are obtained through hydrogen evolution rate measurements, mass loss, and galvanostatic discharge. EIS data are interpreted using a physically motivated two-time-constant model separating charge-transfer resistance and passive-film resistance, enabling a direct mapping between film stability and hydrogen evolution suppression. The results demonstrate that heat treatments that homogenize intermetallic distributions and reduce cathodic connectivity increase passive-film resistance, shift pitting potentials to more noble values, and raise anodic efficiency under discharge. The proposed workflow provides a transferable methodology for optimizing multiphase aluminum anodes by jointly maximizing protective-film integrity and minimizing parasitic hydrogen evolution.

aluminum anode,Al--air battery,alkaline corrosion,electrochemical impedance spectroscopy,hydrogen evolution,heat treatment,intermetallics,anodic efficiency