Environmentalists
often use the term “reduce, reuse, recycle” to describe ways that
individuals can shrink their footprint on the planet. But the phrase
applies on industrial scales as well, and a recent report suggests that
there is a way for the renewable energy industry to reuse something in
order to substantially reduce its environmental impact with a similarly
large savings in costs. A couple of weeks ago, the journal Cell Reports Physical Science published an article titled “Taking Second-Life Batteries from Exhausted to empowered using experiments, data analysis, and health estimation”
by a team from Stanford University and Relyion Energy in California led
by Xiaofan Cui. The paper talks about the potential for using retired
car batteries as storage in the electrical grid. The basic premise is
that a typical retired car battery still maintains 70 to 80% of its
energy storage potential, and that 40% of the projected need for energy
storage in the grid by 2030 can be supplied by these retired batteries.
The primary logistical issue for using these batteries is that they
will need to be repurposed, so this study set out to test whether this
issue is a barrier or merely a small obstacle.
The authors tested
eight cells from retired Nissan Leaf battery packs for their ability to
continue supplying electricity once repurposed. The results show that
the reduced-voltage state that comes with supplying grid power instead
of moving a vehicle can substantially extend the usable lifetime of the
battery. While the sample size was tiny and these results do depend
significantly on the health of the battery when it is retired, the
authors did establish proof of concept. And if these results can be
replicated on a bigger scale, the technology has game-changing
potential. I’ve discussed in a previous post
that the cost of battery storage, while declining, remains high enough
to slow down the adoption of renewable energy. But if much of the
needed storage can come from batteries that are otherwise headed for the
scrap heap, that would reduce the overhead enormously while
simultaneously enhancing sustainability. It is worth paying attention
to see how this story develops.
