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Strategy to Nonlinearly Deplete Irreversible Li Consumption in Si-rich Li-Ion Batteries

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 نشر من قبل Ken Ogata
 تاريخ النشر 2017
  مجال البحث فيزياء
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Despite recent significant developments of Si composites, use of silicon with significance in the anodes for Li-ion batteries is still limited. In fact, nominal energy density is to be saturated around ~750 Wh/L regardless of cell-types under the current material strategies. Use of Si-rich anode can push the limit; however, the prolonged irreversible Li consumption becomes more prominent. We previously showed that repeating c-Li3.75(+{delta})Si formation/decomposition, typically recognized to degrade the anodes, can improve the irreversibility and accumulatively minimize the gross consumption. Utilizing the insights combined with prelithiation techniques, here we provide prototypic cell designs that can nonlinearly deplete the consumption.

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