The battery that never runs out.

The battery that never turns out in your lifetime.
University of California, Irvine [UCI] breakthrough may extend the life of computers, smartphones and appliances

Mya Le Thai a PhD student at UCI has accidentally ended up with a battery claimed to last more than 100k cycles, 400 years [extrapolated results]. 

The results was published in ACS energy letters, April 20, 2016.

source; https://news.uci.edu/feature/better-batteries-through-chemistry/