New battery could lead to cheaper solar power

Posted by Kate Taylor

A new type of lithium battery developed by the University of Southampton and lithium battery technology company REAPsystems is claimed to improve the efficiency and reduce the cost of solar power.

"Lead acid batteries are traditionally the energy storage device used for most photovoltaic systems," says student Yue Wu. "However, as an energy storage device, lithium batteries, especially the LiFePO4 batteries we used, have more favourable characteristics."

A lithium iron phosphate battery was connected to a photovoltaic system attached to one of the University’s buildings, using a specifically designed battery management system supplied by REAPsystems.

"The research showed that the lithium battery has an energy efficiency of 95 percent, whereas the lead-acid batteries commonly used today only have around 80 percent," says Yue.

"The weight of the lithium batteries is lower and they have a longer life span than the lead-acid batteries reaching up to 1,600 charge/discharge cycles, meaning they would need to be replaced less frequently."

"For all kinds of energy source (renewable or non-renewable), the energy storage device - such as a battery – plays an important role in determining the energy utilisation," says Dr Dennis Doerffel, founder of REAPsystems and former researcher at the University of Southampton.

"Compared with traditional lead acid batteries, LiFePO4 batteries are more efficient, have a longer lifetime, are lighter and cost less per unit. We can see the potential of this battery being used widely in photovoltaic application, and other renewable energy systems."