Design of symbiosis 3D framework interface for long-life lithium metal batteries

The application of lithium metal in batteries is constrained due to high nucleation potential and uneven deposition. Here, we reported that cellulose film protects lithium by a facile and low-cost method, suitable for high-voltage cathodes in carbonate electrolytes. The cellulose layer can well accommodate the deposited lithium and eliminate volume change in the lithium depositing/stripping processes. Cellulose layer nanofibers are transferred to the surface of lithium foil to form a compact layer of cellulose and lithium metal symbiosis. This can homogenize Li-ions distribution and apply as the lithium deposition sites, decreasing nucleation over potential. The symbiotic layer on the surface of lithium foil has the fast Li+ transmission performance of Li2CO3 and LiF, good electronic insulator capability and strong affinity for Li+, respectively. As a result, Li symmetric cells using the cellulose protected Li exhibited excellent cycling stability over 220 h at 3 mA cm−2. The full cells assembled with a NMC811 cathode (loading of 2.68 mA h cm−2) exhibited high-rate capability and excellent cycle stability, with capacity retention of 71.2 % at 400 cycles.