Graphene Enables Aluminum Current Collectors of 5\nV Class Battery

The\nfive volt-class battery is one promising candidate of high\nenergy density lithium-ion batteries. However, it suffers from limited\nelectrochemical performance due to many problems, one of which is\nAl current collector corrosion. The corrosion greatly affects the\nelectrochemical performance of batteries, so uncovering the Al corrosion\nmechanism and developing its protection strategy in the 5 V-class\nbattery becomes important. Here, we experimentally realize a corrosion-resistant\nAl current collector via graphene protection. The experimental and\ntheoretical calculation indicate that graphene can work as a physical\nbarrier to inhibit direct contact between LiPF<sub>6</sub>-based electrolyte\nand an Al current collector, reducing the side reactions between Al\ncurrent collector and HF originated from electrolyte. What is more,\ngraphene increases the Al corrosion reaction potential, raising the\ndifficulty of electrochemical corrosion. These effects improve the\nelectrochemical performance of the 5 V-class battery, especially the\nrate performance and cycling stability. The work is beneficial for\nthe development of a 5 V-class battery.