Devitrified silica minerals glass was obtained from stoichiometric tanohataite (LiMn2Si3O8F) mineral prepared by melt quench route. Low-quartz and cristobalite (∼19.5 %) were developed in glass during melt cooling and casting the glass melt. However, a scanning electron microscope (SEM) for the devitrified glass showed nanoscale particles scattered in a few crystallized spots. When it was tested as an anode for lithium-ion batteries, a relatively high initial capacity of ca.785 mAh g−1 was obtained at 50 mA g−1 as an initial discharge capacity. Very good stability with excellent capacity retention (sometimes it exceeds 100 %) was observed based on the 2nd discharge capacity until the 500th cycle with about 100 % coulombic efficiency. The sample showed good rate capability as it still delivers a capacity of 26 mAh g−1 after increasing the current density 40 times of magnitude. Also, it is a flexible material as after this considerable load, it can restore 185 mAh g−1 after returning to the initial low current (50 mA g−1). The electrochemical performance was supported by electrochemical impedance (EIS) measurement, which showed a decrease in EIS and an increase in lithium diffusion upon extended cycling. This unique electrochemical performance for this multicomponent non-crystalline glass was formerly supported by XPS characterization, which emphasized the presence of Mn4+ in the synthesized sample.
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