You are actually absolutely correct, silicon and all! https://en.wikipedia.org/wiki/Nanowire_battery https://en.wikipedia.org/wiki/Nanowire_battery The reason

You are actually absolutely correct, silicon and all! https://en.wikipedia.org/wiki/Nanowire_battery https://en.wikipedia.org/wiki/Nanowire_battery The reason why is different and it doesn't solve dendrites, but your conclusions are spot on.