Electric vehicles that typically weigh more than gasoline-powered cars can easily crash through steel highway guardrails that are not designed to withstand the extra force, raising concerns about the nation’s roadside safety system, according to crash test data released Wednesday by the University of Nebraska. Electric vehicles typically weigh 20% to 50% more than gas-powered vehicles thanks to batteries that can weigh almost as much as a small gas-powered car. And they have lower centers of gravity. Because of these differences, guardrails can do little to stop electric vehicles from pushing through barriers typically made of steel. Last fall, engineers...