The cycle performance of Li–O2 batteries is significantly enhanced by using a PU/SiO2/GF nanocomposite separator, which effectively protects the Li anode from corrosion by soluble oxidative intermediates from the ORR, and the dendritic growth of Li crystals during cycling is also inhibited.

The cycle life and capacity of Li–O2 batteries were significantly enhanced by low rate pre-activation, in association with reconstructed homogeneous and compact SEI layers on the Li anode.

Protecting an anode from deterioration during charging/discharging has been seen as one of the key strategies in achieving high-performance lithium (Li)−O 2 batteries and other Li−metal batteries with a high energy density. Here, we describe a facile approach to prevent the Li anode from dendritic growth and chemical corrosion by constructing a SiO 2 /GO hybrid thin layer on the surface. The uniform pore-preserving layer can conduct Li ions in the stripping/plating process, leading to an effective alleviation of the dendritic growth of Li by guiding the ion flux through the microstructure. Such a preservation technique significantly enhances the cell performance by enabling the Li− O 2 cell to cycle up to 348 times at 1 A•g −1 with a capacity of 1000 mA•h•g −1 , which is several times the cycles of cells with pristine Li (58 cycles), Li−GO (166 cycles), and Li−SiO 2 (187 cycles). Moreover, the rate performance is improved, and the ultimate capacity of the cell is dramatically increased from 5400 to 25,200 mA•h•g −1 . This facile technology is robust and conforms to the Li surface, which demonstrates its potential applications in developing future high-performance and long lifespan Li batteries in a cost-effective fashion.

One of the recent challenges in Li-O2 battery technology is the cycle life, which can be severely shortened by cathode passivation induced by discharge product accumulation; this can be eliminated by reducing the amount of discharge products. Herein, we report a feasibility study on the development of a Ga-Sn liquid metal (LM) functionalized multi-walled carbon nanotubes (MWNTs) cathode. In a comparison of MWNT, LM, m-LM/MWNT (pre-mixed LM and MWNTs), and LM/MWNT (LM modified MWNTs) cathodes, morphology analysis showed that small Li2O2 flakes rather than large crystals grown on the conductive Ga-Sn LM and MWNTs of the LM/MWNT cathode only. The decomposition of the flaky Li2O2 on the LM/MWNT cathode occurred at lower charge overpotentials, resulting in low polarization; thus, the cathode passivation and the consumption of the Li anode were both alleviated during the cyclic process. The LM/MWNT cathode significantly improved the cycle life, rate performance and ultimate capacity of Li-O2 batteries.

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