Envia Systems battery breakthrough for affordable 300 mile range electric cars
Lithium battery startup company Envia Systems plans to announce tomorrow, at the ARPA-E conference, development of a high energy density lithium battery (400 watt-hours per kilogram) which could be the tipping point enabling long range affordable electric cars. Long range electric cars have been possible for quite awhile, Solectria built one in the 1990's, and Tesla Motors has been selling the Roadster and will soon be selling the Model S with battery packs sufficient for 200-300 miles of all electric driving range. What Envia brings to this is higher energy density and lower cost, a combination which would make for an affordable, long range, electric car with a 300-mile range and a price around $25,000 to $30,000.
The company is a Silicon Valley startup founded in 2007, headquartered in Newark CA, and with a prototyping and manufacturing plant in Jiaxing China. The company received a $4 million ARPA-E award in the High Energy Density Lithium Batteries program, as well as significant amounts of private investment from GM Ventures and others.
Envia's technology is a new cathode design for lithium-Ion batteries which the company calls the High Capacity Manganese Rich (HCMR) cathode. It's claimed the design has excellent stability, long lifetime in charge cycles, and a high per cell voltage. The company has also designed anode and electrolyte materials required to build complete batteries. Batteries have a positive terminal (the anode), a negative terminal (the cathode), and an electrolyte mix between the two. Electrons move between the anode and cathode through the electrolyte.
Envia's cathode design is due in part to technology the company licensed a year ago from Argonne National Labs.
The result is a battery that stores 400 watt-hours of electricity per kilogram, compared to the 100-200 watt-hours/kilogram for todays lithium-ion batteries. Envia says its battery cell costs could be as low as $125 per kilowatt-hour. It's difficult to get accurate prices automakers pay for batteries, but it's thought to be in the neighborhood of $5-600 per kilowatt-hour. Together this means Envia has achieved a breakthrough of over twice the energy density of todays batteries, at 1/4 or less the cost.