Si-alloy negative electrodes for Li-ion batteries

The use of Si-alloys as negative electrode materials in Li-ion cells can increase their energy density by as much as 20%, compared to conventional graphite electrodes. However, several technical challenges related with the massive volume expansion associated with Si-alloy lithiation have impeded their implementation. A number of advances in recent years have occurred in the understanding of these challenges and in means of overcoming them through new materials, electrolyte additives, binders and electrode formulations. Here, the current understanding of these challenges and the latest advances in the field are reviewed.