A novel class of resource-efficient, woven-glass-grid current collectors (CCs) for Li-ion batteries is introduced. These CCs are based on ultra-light multifilament glass threads, woven to a grid and surrounded with a thin metal layer (equivalent to a 1 µm-thick metal foil) in a roll-to-roll physical vapor deposition process. This saves > 90% of the required Cu and Al metals and reduces the mass of the CCs by > 80%. At the same time, the gravimetric capacity of anodes with graphite and cathodes with LiCoO2 active material increases by 48% and 14%, respectively, while full cells are characterized by an increase of 26%. Thus, the specific energy can be improved by 25%. A complete anode and cathode fabrication process from preparing the CCs and electrodes to cells is described and demonstrated in coin cell format. Coin cells with woven-glass-grid CCs achieved 300 cycles with a capacity retention of 93%, a Coulombic efficiency of > 99.9%, and a higher rate capability until a C-rate of 3C. This technology opens up new possibilities for designing ultralight CCs with dedicated surface properties for Li and beyond Li batteries.
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