By optimizing the main materials in lithium‐air batteries, namely sulfolane as electrolyte solvent, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as electrolyte salt, carbon paper as current collector, and Li2O2–C hybrids as positive electrode materials, a performance of 800 cycles with a specific capacity of 1000 mAh g−1 (based on the total mass of positive electrode materials) and an average energy efficiency of 74.72% has been achieved in this work and for the first time reported in the field of lithium‐air battery. Sulfolane‐based electrolyte and carbon paper current collector play the most critical role in building such a lithium‐air battery of high cycle life. The findings described here are expected to benefit the pursuit of green, sustainable, and high‐performance lithium‐air batteries.

International audienceCathode structure plays a vital role in lithium-air battery for that it can provide space for discharged products accommodation and free path for oxygen, e− and Li+ transport. However, pore blockage, cathode passivation and degradation all result in low discharge rates and poor cycling capability. To get rid of these predicaments, a novel highly conductive dual pore carbon aerogel based air cathode is fabricated to construct a lithium-air battery, which exhibits 18 to 525 cycles in the LiTFSI/sulfolane electrolyte at a current density varying from 1.00 mA cm−2 to 0.05 mA cm−2, accompanied by a high energy efficiency of 78.32%. We postulate that the essence lies in that the as-prepared air cathode inventively create a suitable tri-phase boundary reaction zone, facilitating oxygen and Li+ diffusion in two independant pore channels, thus realizing a relative higher discharge rate capability, lower pore blockage and cathode passivation. Further, pore structure, carbon loading, rate capability, discharge depth and the air's effect are exploited and coordinated, targeting for a high power and reversible lithium-air battery. Such nano-porous carbon aerogel air cathode of novel dual pore structure and material design is expected to be an attractive alternative for lithium-air batteries and other lithium based batteries

Conversion-type batteries with electrode materials partially dissolved in liquid electrolyte exhibit high specific capacity and excellent redox kinetics, but currently poor stability due to the shuttle effect. Using solid-electrolyte separator to block the mass exchange between cathode and anode can eliminate the shuttle effect. A stable interface between the solid-electrolyte separator and the liquid electrolyte is essential for the battery performance. Here we demonstrate that a stable interface with low interfacial resistance and limited side reactions can be formed between the sulfide solidelectrolyte β-Li3PS4 and the widely used ether-based liquid electrolytes, under both reduction and oxidation conditions, due to the rapid formation of an effective protective layer of ether-solvated Li3PS4 at the sulfide/liquid electrolyte interface. This discovery has inspired the design of a β-Li3PS4 coated-solid electrolyte Li7P3S11 separator with A c c e p t e d m a n u s c r i p tsimultaneously high ion conduction ability and good interfacial stability with liquid electrolyte, so that hybrid Li-S batteries with this composite separator conserve high discharge capacity of 1047 mA h g -1 and high 2 nd discharge plateau of 2.06 V after 150 cycles.

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