I do research in Li-ion battery anodes.  High performance materials with exceptional charge capacity, cycling capability, safety, and cost are frequently discovered, but the materials almost never have <i>all</i> of those properties at once, and that is essential to getting a product to market.  Most of the new materials with high charge capacity or good cycling performance are very exotic, and thus it is too difficult or expensive to mass produce them.<p>In my opinion, hybrid Si&#x2F;C anodes show the most promise as a material that would realistically be found in Li-ion batteries in the next decade.  Nanowires&#x2F;nanospheres do not seem as promising to me, unless we can find a way to cheaply produce them.