A lithium-air flow battery has minimal cathodic product precipitation, thus extending capacity. The lithium-air flow battery includes a flow electrolyte, flowing proximal to the air cathode, the flow electrolyte having little to no intrinsic lithium ion content. Operation of the lithium-air flow battery generates a lithium-ion concentration gradient across the flow electrolyte, with the lowest lithium-ion concentration adjacent to the air cathode. The extremely low lithium-ion concentration at the cathode, combined with the flow condition at the cathode, results in a minimum of solid product accumulation at the cathode, enabling the cathode to catalyze oxygen reduction for an extended duration.