Na-ion Batteries have been considered as promising alternatives to Li-ion batteries due to the natural abundance of sodium resources. Searching for highperformance anode materials currently becomes a hot topic and also a great challenge for developing Na-ion batteries. In this work, a novel hybrid anode is synthesized consisting of ultrafi ne, few-layered SnS 2 anchored on few-layered reduced graphene oxide (rGO) by a facile solvothermal route. The SnS 2 /rGO hybrid exhibits a high capacity, ultralong cycle life, and superior rate capability. The hybrid can deliver a high charge capacity of 649 mAh g −1 at 100 mA g −1 . At 800 mA g −1 (1.8 C), it can yield an initial charge capacity of 469 mAh g −1 , which can be maintained at 89% and 61%, respectively, after 400 and 1000 cycles. The hybrid can also sustain a current density up to 12.8 A g −1 (≈28 C) where the charge process can be completed in only 1.3 min while still delivering a charge capacity of 337 mAh g −1 . The fast and stable Na-storage ability of SnS 2 /rGO makes it a promising anode for Na-ion batteries.

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LiFexMn1−xPO4 exhibits excellent rate capability and superior cycling stability due to its small size, ultrathin structure and uniform Fe doping.

Lithium-air (Li-air) battery works essentially based on the interfacial reaction of 2Li + O2 ↔ Li2O2 on the catalyst/oxygen-gas/electrolyte triphase interface. Operation of Li-air batteries in ambient air still remains a great challenge despite the recent development, because some side reactions related to moisture (H2O) and carbon dioxide (CO2) will occur on the interface with the formation of some inert byproducts on the surface of the catalyst. In this work, we investigated the effect of H2O and CO2 on the electrochemical performance of Li-air batteries to evaluate the practical operation of the batteries in ambient air. The use of a highly efficient gold/δ-manganese-dioxide (Au/δ-MnO2) catalyst helps to understand the intrinsic mechanism of the effect. We found that H2O has a more detrimental influence than CO2 on the battery performance when operated in ambient air. The battery operated in simulated dry air can sustain a stable cycling up to 200 cycles at 400 mA g(-1) with a relatively low polarization, which is comparable with that operated in pure O2. This work provides a possible method to operate Li-air batteries in ambient air by using optimized catalytic electrodes with a protective layer, for example a hydrophobic membrane.