FORTUNE -- Venture capitalist John Doerr today said at TC Disrupt that the real energy "game changer" would be tripling battery life, rather than the incremental increases we've seen over the past several years. Then he said that he has invested in a start-up that has pulled off the feat in a lab, but declined to identify it.
I'm not 100% certain, but the company Doerr referred to may be Quantumscape, a stealthy San Jose-based startup led by former Infinera (infn) co-founder and CEO Jagdeep Singh. Investors include Kleiner Perkins Caufield & Byers (where Doerr is a partner) and Khosla Ventures.
Quantumscape's website says nothing beyond that it is seeking "a new future through better energy storage."
But we know that the company's technology began at Stanford University, which received an ARPA-E grant for a project that was supposed to create a "quantum leap forward in energy storage." More from the proposal:
"Researchers will seek to develop an 'AllElectron Battery,' a completely new class of electrical energy storage devices for electric vehicles. The new battery stores energy by moving electrons rather than ions and uses a novel architecture that has potential for very high energy density."
A recent Quantumscape job posting suggests that the company is still focused on car batteries, although there also has been past mention of military applications. The company also recently leased an 87,000 square foot facility
Doerr declined to confirm for this story, adding that Kleiner Perkins has "several battery investments." According to the KP website, others include Amprius, Aquion Energy, eSionic and Primus Power.
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