A
joint research project between the University
of Southampton and
lithium battery technology company REAPsystems has found that a new type of
battery has the potential to improve the efficiency and reduce the cost of
solar power.
The
research project, sponsored by REAPsystems, was led by MSc Sustainable Energy
Technologies student, Yue Wu and his supervisors Carlos Ponce de Leon, PhD;
Professor Tom Markvart; and John Low, PhD, (currently working at the
University’s Research Institute for Industry, RIfI). The study looked
specifically into the use of lithium batteries as an energy storage device in
photovoltaic systems.
Student
Yue Wu says, “Lead acid batteries are traditionally the energy storage device
used for most photovoltaic systems. However, as an energy storage device,
lithium batteries, especially the LiFePO4 batteries we used, have more
favourable characteristics.”
Data
was collected by connecting a lithium iron phosphate battery to a photovoltaic
system attached to one of the University’s buildings, using a specifically
designed battery management system supplied by REAPsystems.
Yue
adds, “The research showed that the lithium battery has an energy efficiency of
95% whereas the lead-acid batteries commonly used today only have around 80%.
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.”
Although
the battery will require further testing before being put into commercial
photovoltaic systems the research has shown that the LiFePO4 battery has the
potential to improve the efficiency of solar power systems and help to reduce
the costs of both their installation and upkeep. Carlos Ponce de Leon, PhD, and
John Low, PhD, now plan to take this project further with a new cohort of
Masters students.
Dennis
Doerffel, PhD, founder of REAPsystems and former researcher at the University of Southampton, says; “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 utilization.
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.”