1 research outputs found
Stabilizing Lithium-Metal Host Anodes by Covalently Binding MgF<sub>2</sub> Nanodots to Honeycomb Carbon Nanofibers
Constructing lithiophilic carbon
hosts has been regarded as an
effective strategy for inhibiting Li dendrite formation and mitigating
the volume expansion of Li metal anodes. However, the limitation of
lithiophilic carbon hosts by conventional surface decoration methods
over long-term cycling hinders their practical application. In this
work, a robust host composed of ultrafine MgF2 nanodots
covalently bonded to honeycomb carbon nanofibers (MgF2/HCNFs)
is created through an in situ solid-state reaction. The composite
exhibits ultralight weight, excellent lithiophilicity, and structural
stability, contributing to a significantly enhanced energy efficiency
and lifespan of the battery. Specifically, the strong covalent bond
not only prevents MgF2 nanodots from migrating and aggregating
but also enhances the binding energy between Mg and Li during the
molten Li infusion process. This allows for the effective and stable
regulation of repeated Li plating/stripping. As a result, the MgF2/HCNF-Li electrode delivers a high Coulombic efficiency of
97% after 200 cycles, cycling stably for more than 2000 h. Furthermore,
the full cells with a LiFePO4 cathode achieve a capacity
retention of 85% after 500 cycles at 0.5C. This work provides a strategy
to guide dendrite-free Li deposition patterns toward the development
of high-performance Li metal batteries