High performance Li–CO2 batteries with NiO–CNT cathodes

Rechargeable Li–CO2 batteries are promising energy storage systems for reducing fossil fuel consumption and mitigating the “greenhouse effect” due to the use of a reversible reaction between lithium and CO2. However, current Li–CO2 batteries still suffer from several unresolved problems such as high charge potential and low coulombic efficiency, and hence more efforts are required to optimize their electrochemical performance. In this work, a composite of sheet-like NiO dispersed on carbon nanotubes was prepared via a solvothermal method. The composite was employed as an efficient air cathode for Li–CO2 batteries, with very high coulombic efficiency (97.8%) and good cycling stability (40 cycles). This study provides new strategies to develop cheap and abundant catalysts to improve the performance of Li–CO2 batteries.