Researchers have developed a novel method to produce high-performance ultra-thin lithium metal anodes for next-generation batteries using vacuum thermal evaporation. This technique creates lithium anodes with a passivation layer approximately 10 times thinner than conventional extruded lithium, resulting in significantly improved battery performance. The study published in Communications Materials.
The evaporated lithium anodes exhibited much lower charge-transfer resistance and more uniform lithium plating and stripping during battery cycling compared to extruded lithium. In full cell tests, batteries with evaporated lithium anodes demonstrated triple the cycle life with NMC622 cathodes in carbonate electrolyte and 30% longer cycle life with LFP cathodes in ether electrolyte. They also showed higher first cycle Coulombic efficiency and improved fast-charging capability at high C-rates.
Detailed analyses revealed the evaporated lithium had a smoother surface morphology with larger grains and fewer impurities than extruded lithium. The vacuum thermal evaporation technique allowed precise control over the lithium layer thickness, with 25 μm anodes produced to match commercial extruded lithium.
The researchers propose this scalable method as a promising approach for producing high-performance lithium anodes for next-generation high energy density batteries. They suggest it could enable further optimization of lithium metal anodes, potentially even allowing for passivation-free anodes through subsequent protective layer evaporation.
This work represents an important advance in addressing key challenges facing lithium metal batteries, particularly dendrite formation and limited cycle life. By fundamentally altering the surface properties of lithium metal anodes, this technique offers a promising route to unlocking the full potential of lithium metal battery chemistry.
Reference: High performance ultra-thin lithium metal anode enabled by vacuum thermal evaporation,
Nicolas Rospars, Mohammed Srout et al., Communications Materials 2024, DOI: 10.1038/s43246-024-00619-9
Source: Nature Communications-Materials
