An American company, Envia, has tested a new lithium-ion battery that will allow an electric car to travel 300 miles at half the price of the current model. The battery has set a new world record in energy density, and the company aims to ready it for large-scale production in a mere 18 months. If it holds up to the hype, the battery will allow companies to slash the price on electric cars like GM’s Chevy Volt, which currently sells for $41,000.Via Meadia is cautiously optimistic these promises will deliver, although many of these “breakthroughs” fail to materialize after the flurry of press releases and breathless publicity has passed. We can wait to applaud Envia’s achievement until the battery is actually being used in cars that are selling in significant numbers. Last time we checked, there weren’t many Volts on the road.That said, we certainly hope to see more progress in this field. Battery technology is a choke point in many industries that need better, cheaper and more effective storage of power. Envia receives funding from the U.S. Department of Energy and GM, among others. In general, Via Meadia supports this kind of partnership and investment in research, provided that research funding doesn’t turn into production subsidies.Whether or not this particular battery concept pays off, it’s worth noting that unpredictable technological innovations like these mean that linear projections about future CO2 emissions are basically hot air.