The tobacco mosaic virus makes its living by munching on tobacco plants and other vegetables. Researchers have somehow figured out that by slathering the virus onto battery electrodes, it can increase battery capacity by a factor of ten.
The process starts with a strain of virus that's been genetically modified so that one end of it will bond to a metal plate. This hacked virus gets a tasty new home on the leaf of a tobacco plant, and when the entire plant is infected after a week or two, it's crushed and the virus is harvested. The virus gets deposited onto a piece of metal, where the genetic modifications cause one end of each individual virus to stick to the metal while the other end points straight up, creating an entire forest of little virus nanotrees. The last step is to coat the virus forest with a conductive layer, which renders the viruses themselves harmless, makes the structure durable, and turns the whole thing into a functional battery with a capacity up to ten times normal.
This magnitude increase in capacity comes from the the virus nanotrees, which increase the surface area of the electrode by ten times, giving you ten times the room to store electricity. And while the process sounds complicated, it's not. Or at least, it has the potential not to be, once it makes it out of the lab. The virus self replicates, the tobacco plants that it lives in self replicate, and one acre of infected plants yields about a ton of battery virus. The nanostructure builds itself without needing a bonding agent, and once scaled up to an industrial level, it would be easier and cheaper to build batteries like this than it is to make batteries the way we do now.
Increasing capacity by a factor of ten also means that, if you want, you can instead decrease size by a factor of ten while keeping the same capacity. Or, split the difference. Either way, it means batteries are getting an extra infectious dose of awesome.