Abstract: Methods and systems for electrolyte regeneration are provided, which regenerate a spent alkaline electrolyte (SE) comprising dissolved aluminum hydrates from an aluminum-air battery, by electrolysis, to precipitate aluminum tri-hydroxide (ATH) and form regenerated alkaline electrolyte, and adding a same-cation salt to an anolyte used in the electrolysis to supplant a corresponding electrolyte cation. The regeneration may be carried out continuously and further comprise mixing the SE and the same-cation salt in a salt tank configured to deliver the anolyte, removing the regenerated alkaline electrolyte from a catholyte tank configured to deliver the catholyte, and filtering the ATH from a solution delivered from the salt tank to the anolyte. Optionally, the salt may be a buffering salt, and in some cases chemical reactions may be used to enhance the regeneration by electrolysis.