Silicon (Si) Alloying Anodes in Lithium Batteries
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As listed in Table 1368, silicon (Si) alloying anodes provide theoretical capacities more than 10 times that of
intercalating anodes. However, during the alloying/de-alloying reactions, there is a volume expansion up to 300% in the Si alloying anodes. Such volume expansion can break up the electrode, resulting in reduced capacity and shorter cycle life of <200 cycles. Nano particle-Si, Si nano-wires, porous Si and Si graphite blends have recently been proposed to minimize the problems that are caused by volume expansion.

Table 1368. Comparison of the properties of some typical anodes.

  LTO (lithium titanate oxide) Graphite Silicon
Type Intercalation Intercalation Alloying
Theoretical capacity mAh/g 175 330 4200
Voltage vs Li/Li+ (V) 1.5 0.1 0.1
Current collector Aluminium Copper Copper
Main disadvantages Low voltage & low energy density cell Safety issues Volume expansion (up to 300%), poor cycling ability