Working in tandem, the University of Southampton and lithium battery technology company REAPsystems have discovered that a new type of battery has the potential to increase the efficiency and reduce the cost of solar power.
The study looked specifically at the use of lithium batteries as a storage method for solar power in photovoltaic systems and found that they were a more efficient method than the lead acid batteries currently used in most systems.
“Lead acid batteries are traditionally the energy storage device used for most photovoltaic systems,” said lead researcher Yue Wu, a MSc Sustainable Energy Technologies student. “However, as an energy storage device, lithium batteries, especially the LiFePO4 batteries we used, have more favourable characteristics.”
Data for their research was acquired by connecting a lithium iron phosphate battery to a photovoltaic system attached to one of the University of Southampton’s buildings using a specifically designed battery management system that was provided by REAPsystems.
“The research showed that the lithium battery has an energy efficiency of 95 per cent whereas the lead-acid batteries commonly used today only have around 80 per cent,” added 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.”
The LiFePO4 battery appears to have the potential to improve the efficiency of solar power systems, as well as reducing the cost of both their installation and their upkeep. But more testing will be required before being implemented in commercial photovoltaic systems.
“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,” said 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.”