We need energyenergy/ˈen.ər.dʒi/L1能量the power that makes things work or move from the sun and the windwind/wɪnd/L1风moving air. The sun does not always shine, and the wind does not always blow. So we need batteries to store this energy. Scientists in Belfast made a new battery, and it is cheapcheap/tʃiːp/L1便宜的not costing a lot of money.
Old batteries use a metal called vanadium. It is hard to find and costs a lot of money. The new battery uses ironiron/ˈaɪ.ərn/L1铁a common metal. Iron is easy to find and costs very little. The scientists 3D-printed the battery and shared the design for free. "It is fun to see our work help everyone," said Dr. Bailey.
