Current Density Regulating Lithium Metal Directional Deposition for Long Cycle Life Lithium Metal Batteries

Uncontrolled dendrite formation in the high energy density of lithium metal batteries (LMBs) may pose serious safety risks. Numerous works have been reported to protect separator. However, these methods still couldn’t inhibit the dendrite upward growth to protect the separator, effectively. Here, we introduce a novel “orientated-growth” strategy that makes the depositional interface transfer to the anode/current collector interface from the anode/separator interface. We placed a layer of cellulose/graphene carbon composite aerogel (CCA) between the current collector and the anode (CCA-Li). This layer works as the charge organizer; it induces a higher current density distribution and makes Li prefer to deposit in the bottom CCA layer of CCA-Li electrode. Both in-situ and ex-situ images of the electrode demonstrate the anode part of the cell has been flipped; with the new deposited particles facing the current collector and smooth surface facing the separator. Electrochemical characterization of the electrode in half and full cells showed outstanding cyclic stability and rate capability, with the CCA-Li/LPF full cell able to maintain 94% of its initial capacity after 1000 cycles. We believe that the innovative strategy would promote the leapfrog development for LMBs.