Bio-Inspired Stable Lithium-Metal Anodes by Co-depositing Lithium with a 2D Vermiculite Shuttle

Progress in lithium-metal batteries is severely hindered by lithium dendrite growth. Lithium is soft with a mechanical modulus as low as that of polymers. Herein we suppress lithium dendrites by forming soft-hard organic-inorganic lamella reminiscent of the natural sea-shell material nacres. We use lithium as the soft segment and colloidal vermiculite sheets as the hard inorganic constituent. The vermiculite sheets are highly negatively charged so can absorb Li+ then be co-deposited with lithium, flattening the lithium growth which remains dendrite-free over hundreds of cycles. After Li+ ions absorbed on the vermiculite are transferred to the lithium substrate, the vermiculite sheets become negative charged again and move away from the substrate along the electric field, allowing them to absorb new Li+ and shuttling to and from the substrate. Long term cycling of full cells using the nacre-mimetic lithium-metal anodes is also demonstrated.