Other researchers worked on a slightly different power source. It is called a fuel cell. A fuel cell could be twice as strong as a lead-acid battery. But, even today, it is too heavy and costly. Researching was also studied. Drivers wouldn't mind stopping to often for a recharging if it took only minutes. Still another idea was to design a lighter car. Then a regular battery could push it faster and farther. Today many design are being tested. Large and small companies and even people on their own are building electric. Reports say that work is moving ahead.