Reuters: Ener1 Inc will be able to cut the cost of batteries for hybrid electric vehicles by 50 percent once its lithium-ion technology amasses scale, Chief Executive Charles Gassenheimer said on Friday. The company, which has yet to sign a supply agreement with a major auto manufacturer, also said it expects to secure two new battery development deals by the end of this year. Those could eventually turn into mass-production agreements. Ener1’s lithium-ion battery unit, EnerDel, is …