In October 2013 the state of California mandated
gigawatt-scale energy storage onto its electricity grid,
following Germany’s lead earlier this year.
While not front page news, this decision by two very
different, very influential and very hi-tech economies
signifies a milestone nevertheless. For it marks the point
in time when we stopped asking how renewables might
suit the grid and started asking how we might adapt the
grid to suit renewables.
Grids and microgrids – particularly renewable-ready
grids – require energy storage that can simultaneously
smooth instabilities and shift energy to better cope with
peak demands. Such storage must be always ready.
That means ready not only to shift energy from noon to
the evening peak, but also ready to rapidly accept and
rapidly deliver very high rates of charge.
Such highly responsive storage – or ‘active storage’ – is
difficult to implement; few storage technologies do
it well. But put a lead-acid cell and an ultracapacitor
together in a common electrolyte and suddenly your
energy storage becomes more than just available for
occasional use – it becomes an UltraBattery®, a true
constant-use storage technology.
The outstanding benefit of the UltraBattery® is its
long life under cycling operations at partial state of
charge. Three national laboratories in the USA have
undertaken independent UltraBattery® testing programs
for Hybrid Electric Vehicles (HEV) and grid applications,
demonstrating the longevity of the UltraBattery® under
low-rate and high-rate cycling.
Many batteries claim lifetimes of hundreds of partial state
of charge cycles. Some claim over one thousand cycles.
In Sandia National Laboratory high-rate, partial state-
of-charge tests (about as demanding as a battery test
gets) UltraBattery® cells ran for more than 20,000 cycles
maintaining essentially 100% of their initial capacity.
East Penn Manufacturing UltraBattery® VRLA VRLA receives recovery charge
Endurance of UltraBattery® Technology
5,000 10,000 15,000 20,000 25,000 0
Results from Sandia National Laboratory testing in 2012
display the endurance of UltraBattery® technology in
demanding partial state of charge applications.
And that’s just the start. The same characteristics
make UltraBattery® a standout choice for HEVs. In an
Advanced Lead Acid Battery Consortium’s (ALABC)
test, an UltraBattery® pack recorded over 100,000 miles
of real-world courier duty in an HEV in the demanding
climate of Phoenix, Arizona. No significant loss in battery
capacity was found.
A simulated driving test is ongoing on a lab-based
UltraBattery® pack. No conditioning or equalization
charges have been performed during the test. No major
decrease in the pack voltage has been observed. Five
thousand full capacity turnovers have been performed
and the test has just completed 1. 2 million partial state
of charge cycles.
And you thought you knew batteries.
Get ready to meet UltraBattery®. Active storage for
the renewable-ready grid.
Two quiet revolutions – the grid waking up to energy storage and
an in-cell ultracapacitor overturning a century of lead-acid chemistry
– have suddenly made UltraBattery® the storage technology to
watch. And the test results keep getting better…