LOCALIZED HIGH SALT CONCENTRATION ELECTROLYTE

A battery includes a cathode comprising a disordered rocksalt structure and an electrolyte. The electrolyte includes a solvating solvent and a lithium salt that is soluble in the solvating solvent. The electrolyte includes a diluent that is miscible with the solvating solvent. The lithium salt is at least 5 times more soluble in the solvating solvent than in the diluent, and the solvating solvent and diluent are present in the battery at a diluent ratio/solvating solvent ratio of 0.1 to less than 3.0.