NEC Says Battery Innovations Could Boost EV Range by 30%

Electric vehicles could run 30% farther by switching to a new cathode-electrolyte combination developed by NEC Corp., according to the company.

NEC says its chemistry cuts weight, boosts capacity and increases energy density about 30% compared with conventional lithium-ion batteries.

The new manganese-based cathodes uses nickel rather than costlier cobalt to raise operating voltage to 4.5 volts from the 3.8 volts typical of lithium-ion batteries. NEC says its architecture increases energy density to 200 Wh/kg from 150 Wh/kg.

The company notes that the improvement simplifies battery construction by reducing the number of cells required to achieve a target output. The new chemistry also could be used to maintain power levels with a battery that is 30% lighter than a conventional unit.

NEC's new electrolyte is a fluorinated liquid that resists oxidation significantly better than conventional carbonate-based solvent. The material suppresses decomposition that would otherwise occur between the cathode and electrolyte. The new electrolyte also reduces battery swelling caused by gas formation to 10% compared with 100% for conventional electrolytes, according to NEC.

The company, which hopes to commercialize its technology within two years, is presenting its results today at the Pacific Rim Meeting on Electrochemical and Solid-State Science in Honolulu.