No question that battery technology is one of the things that will have to get better before wearables become truly commonplace. There are several areas of necessary innovation that I can think of:
- power density
A flexible battery that’s huge and doesn’t hold enough power is no good. A small battery that holds a big charge but explodes easily won’t find a market. (This all assumes reasonable levels price and manufacturing ease, although I bet that if the other four problems were solved, the market would make liberal allowance for those two.)
Here’s a really good roundup of the current state of battery development from an investment point of view: who’s building, who’s researching, and who’s paying for it. Zinc batteries (much more stable than lithium-based ones) are of particular interest. So are “printable” batteries — another application of 3-D printing, in case you needed another reason to be interested in it.