We propose self-expanding lithium-ion transport channels to construct a fast-charging anode and realize high-performance fast-charging Li-ion batteries. The self-expanded Li-ion transport channels can be enabled by a self-reversible conversion of chemical bonds with different bond lengths in the anode driven by the interactions with Li ions during cycling, reduce the energy barrier of Li-ion transport and allow a fast Li-ion solid-state diffusion, whereby the severe voltage polarization and Li metal plating are effectively eliminated. Our proof-of-concept demonstration of the self-reversible conversion of chemical bonds on the surface of graphdiyne successfully verifies the self-expanded Li-ion transport channels, self-accelerated Li in-plane/out-of-plane migration, and superior fast-charging capability with a high capacity (342 mA h g-1 ) and an ultra-long lifespan (22 000 cycles) under extremely fast-charging conditions (6 C rate, 1 C=744 mA g-1 ), even at low temperatures (-10 °C).
Keywords: electrochemistry; fast charging; graphdiyne; ion-transport channels; lithium-ion batteries.
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