Metal halide perovskites have been recently proposed as hopeful materials for energy storage applications. Besides, the quite important electrochemical characteristics of these materials, all the perovskite-based anodes are synthesized at high temperatures (90–150 °C) and with reaction durations of the order of tens of hours. In this work, it has been particularly shown that the direct growth of all-inorganic, metal halide microcrystals free of ligands, provides high-performance and stable electrodes for Li-air batteries. We describe a very simple and rapid method to synthesize well-crystalline and ultra-stable, at both ambient and aqueous conditions, CsPbBr3 microcubes, exhibiting prominent electrochemical performance. In particular, it is shown that during the successive scans in which the Li-ions intercalate and deintercalate, the microcubes-based anodes showed a high specific capacity of 549 mAh·g−1 and operation durability up to 1500 cycles. The large interfacial area between the perovskite electroactive material and the electrolyte along with the increase of the active sites on the exposed microcubes facets favor the Li-ions intercalation. It is concluded that the anodes presented here demonstrate the best electrochemical features among the nano- and microparticulate lead halide perovskite anodes used for Li-air batteries, to date.