Nanotechnology enabled rechargeable Li–SO2 batteries: another approach towards post-lithium-ion battery systems†
Extensive research efforts have been devoted to the development of alternative battery chemistry to replace the current technology of lithium-ion batteries (LIBs). Here, we demonstrate that the Li–SO2 battery chemistry, already established 30 years ago, has considerable potential to be regarded as a candidate for post-LIBs when appropriate nanotechnology is exploited. The recently developed nanostructured carbon materials greatly improve the battery performances of Li–SO2 cells, including a reversible capacity higher than 1000 mA h g−1 with a working potential of 3 V and excellent cycle performance over 150 cycles, and provide a theoretical energy density of about 651 W h kg−1, which is about 70% higher than that of the currently used LIBs. The nanostructured carbon cathodes offer not only an enlarged active surface area, but also a mechanical buffer to accommodate insulating discharge products upon discharge. Considering the other outstanding properties of the SO2-based inorganic electrolyte, such as non-flammability and significantly higher ionic conductivities, wisely selected nanotechnology renders the Li–SO2 battery chemistry a very promising approach towards the development of a post-LIB system.