▎ 摘　　要

The main hurdle in the practical exploitation of Li-S batteries lies in the difficulty in loading an adequately large percentage of sulphur in the cathode, without a detrimental impact upon the overall structural integrity over the charge-discharge cycles. Here we demonstrate that as much as 88.5 wt% of sulphur could be effectively coupled with high-conductivity graphene (HCG) powder, using a simple one-step ball milling process to obtain sea sponge-like composites wherein sulphur was effectively accommodated within a framework of three-dimensional (3D) networks of interconnected graphene flakes. On the basis of the extremely low defect density, high C/O ratio (24.64) and ultrahigh electrical conductivity (2.05 x 10(5) S m(-1)), the HCG networks provided 3D super-highways for ionic and electronic transport, while enabling self-healing to help maintain structural integrity. The mechanical alloying effects resulted in S incorporation into the graphene lattice, thus helping to retain polysulphides within the cathodes. This resulted in a very effective utilization of sulphur in the cathode, so that Li-S/HCG battery cells were realized to deliver a remarkably high full-cathode capacity, a high areal capacity and energy density, an excellent rate-performance and a high cycling stability (4.78 mA h cm(-2) and 1642 W h kg(-1) at a sulphur load of 6.0 mg cm(-2); 555.7 mA h g(-1) at 5C; 519 mA h g(-1) at 2C after 500 cycles).