Coping with a dead cell phone while you’re on the go could become yesterday’s problem, thanks to a new organic photovoltaic solar cell that could recharge a standard lithium-ion battery, even in low-light conditions. Scientists at the University of Warwick and spinout Molecular Solar have created an organic photovoltaic (OPV) cell that generates enough voltage to recharge the lithium-ion batteries of portable electronic devices such as e-book readers and cell phones without connecting multiple individual cells in a series. The cells are cheap to produce, lightweight and compatible with flexible substrates. Professor Tim Jones in the lab. He and others at the University of Warwick, and spinout Molecular Solar, have created an organic photovoltaic cell that generates enough voltage to recharge a standard lithium-ion battery, even in low-light conditions. Courtesy of the University of Warwick. Standard lithium-ion batteries need 4.2 V; the team for the first time demonstrated 7 V using an ultrahigh-voltage OPV cell. “We have taken a big step toward cheap-to-make solar chargers which can top up your devices whenever they are being used — both indoors and out,” said professor Tim Jones, one of the project’s leaders. “A small lightweight solar charger no bigger than a credit card can be fitted to the battery of an e-book reader, for example, and constantly top it up with power while you are reading it — even if you are sitting inside on the sofa.” The team hopes to make cheap OPV chargers commercially available soon through Molecular Solar. The study was published online in Advanced Energy Materials (doi: 10.1002/aenm.201200560). For more information, visit: www.warwick.ac.uk