Batteries offer perhaps the greatest opportunity for innovation in the technology realm. Whoever figures out a way to pack a bigger punch into a smaller space will undoubtedly make a lot of money, which perhaps explains why Seeo is seeing so much interest from investors.

The Hayward, California-based company develops rechargeable lithium-ion batteries, and it has just announced the closure of a $17 million Series E round.

But what’s perhaps most interesting about this deal is who’s putting up the cash. The round is being led by Samsung’s investment arm, Samsung Ventures, though earlier investors Khosla Ventures and GSR Ventures are also participating.

Given Samsung’s lofty position in the consumer electronics space, it clearly has a vested interest in seeing better batteries come to the fore. But its involvement here isn’t so much about ensuring it can cram more juice into the next incarnation of its Galaxy smartphones.

According to Seeo, it will use the cash injection to expedite the commercialization of its DryLyte advanced lithium polymer batteries, which sport an electrolyte that enables better energy density, specifically for use in electric vehicles (EVs).

Seeo currently has cells (though not in use commercially) capable of operating with an energy density of 350 Wh/Kg (watt-hour per kilogram), but it’s now targeting 400 Wh/Kg — around double that used in most electric vehicles today. But safety is paramount when developing such batteries, and this is the crux of the technology Seeo is working on.

Non-flammable

Seeo’s DryLyte “solid” polymer electrolyte is non-volatile and non-flammable, which means it can be used at a much higher temperature. Seeo is striving to replace the standard flammable liquid-based electrolytes, typically found in lithium-ion cells, with its own creations.

Why would Samsung be interested in this? Well, it may not be as random as it first seems. Samsung has previously filed for patents in both the U.S. and South Korea for technology that can be used in electric vehicles. These include technology required for making “tires, motors, as well as on-board electronics for information sharing between the car and driver,” as the Wall Street Journal has previously reported.

Samsung has previously denied it plans to enter the electric vehicle space directly, but its tentative steps in that direction would certainly suggest otherwise. Samsung SDI, a subsidiary of the Korean electronics giant, has in fact been working on lithium-ion battery cell technology with BMW since 2009, and the two companies recently announced an extension to their deal for two EV models in particular (the BMW i8 and i3).

This latest funding round takes Seeo past the $40 million mark since its inception back in 2007. It’s probably also worth mentioning another notable previous investor — Google.org, Google’s philanthropic division, was part of Seeo’s $15 million round back in 2011.

Seeo emerged from the Lawrence Berkeley National Laboratory and was developed initially with sponsorship from the US Department of Energy.