Enhanced high-rate discharge properties of La11.3Mg6.0Sm7.4Ni61.0Co7.2Al7.1 with added graphene synthesized by plasma milling

In order to improve the high-rate discharge properties of La11.3Mg6.0Sm7.4Ni61.0Co7.2Al7.1 (AB3.0) alloy electrodes, the effects of plasma milling (PM) and graphene addition on their electrochemical properties and kinetics have been investigated. It was found that the discharge capacity of AB3.0 at a high discharge current density was significantly improved after the addition of graphene followed by PM for only 10 min. Moreover, the high-rate dischargeability (HRD) and the exchange current density I0 of the alloy electrodes were also increased. The PM technique exhibits obvious advantages for improving the high-rate discharge properties of hydrogen-storage alloys. •AB3.0–graphene composites were prepared by plasma milling.•Plasma milling and graphene addition showed synergistic effect.•Improvement of high-rate discharge properties of AB3.0 was realized.•Mechanisms of the Enhanced high-rate discharge properties were explained.