Redistributing Cobalt and Tungsten From WC –Co Soft Scrap Toward Sustainable Cathode and Coating Materials for Lithium‐Ion Batteries

The scarcity of cobalt and tungsten causes unstable supply and sharp price fluctuations, emphasizing the urgent need for recycling and redistribution strategies. Herein, we develop an efficient upcycling route for recovering high‐purity tungsten carbide and cobalt from cemented carbide (tungsten carbide–cobalt) soft scrap via mechanochemical ball milling and solvent extraction, and resynthesizing it into lithium‐ion battery cathode materials. In this process, the residual nickel impurity is repurposed as a stabilizing dopant, reinforcing the layered framework at the cobalt sites of LiCoO 2 and suppressing lattice collapse even under high‐voltage cycling. Benefiting from nickel incorporation at cobalt sites, the resynthesized LiCoO 2 exhibits markedly reduced c‐lattice shrinkage and suppressed phase transitions at high voltages, evidenced by in situ X‐ray diffraction. Such dopant‐induced stabilization enables remarkable electrochemical durability, as resynthesized LiCoO 2 preserves over 60% of its capacity after 1000 cycles at 4.3 V (1 C) and retains 86.78% after 200 cycles at 4.5 V (0.2 C). Simultaneously, the tungsten carbide fraction is converted into tungsten trioxide and employed to modify nickel‐rich layered oxides, mitigating interfacial degradation and improving durability. This cross‐sectoral upcycling strategy exemplifies a circular economy approach by converting cemented carbide soft scrap from hard‐metal applications into cathodes, directly linking industrial waste streams to the lithium‐ion battery supply chain.