Lithium ion conducting membranes for lithium-air batteries

摘要

Materials design and synthesis is critical for reliable fabrication of stable and high-performance lithium-air batteries that are competitive with other energy delivery systems. Intensive research activities have focused on the development of efficient cathode catalysts and stable electrolytes in the past several years and many review articles are already available. This review aims on lithium ion conducting membranes that are barely studied although they are essentially indispensible for building batteries composed of aqueous electrolytes and batteries composed of non-aqueous electrolytes for long-term operation. In a typical lithium-air battery cell, a lithium ion conducting membrane is sandwiched between the lithium metal anode and the air cathode to prevent the lithium metal anode from reacting with poison species (e.g., water, oxygen, etc.) diffused from cathode to anode, leading to a significant increase in lifetime of the battery. A number of solid materials including polymer/polymer-ceramic composites, non-oxide inorganic compounds, perovskite-type oxides, garnet-type oxides, γ-Li_3PO_4 oxides, NASICON-type oxides, and single-crystalline silicon that exhibit good lithium-ion conductivity are comprehensively summarized and discussed in this review. Although only a few of NASICON-type oxides and single-crystalline silicon have been evaluated as the lithium ion conducting membranes in lithium-air battery cells, all of the solid materials summarized in this review and their possible derivative composites are also promising to be developed as lithium ion conducting membranes for lithium-air batteries. This review is also expected to be an advocate for research in lithium ion conducting membranes.