Believe it or not, but the
next generation Lithium-ion
batteries will be produced
from rice husk, an abundant
agricultural waste. Tesla’s
electric cars still depend on
Lithium-ion batteries, a
great technology which was
mainly commercialized by
Sony more than twenty
years ago. Today, right from
laptop to tablets to mobile
phones – everything’s been
powered by Lithium-ion
batteries. Now is a time for
recharge and change! Like
technological advancements
are made in every field,
Lithium-ion batteries’ being
an important component of
renewable energy methods
and essential for modern
technological progress is
also expected to perform
better.
Lithium-ion batteries are
still one of the best as well
as expensive components of
any type of electric cars,
which is one of the reasons
why the electric or battery
powered vehicles still
depend on economic
subsidies. But there are
other niggling issues too.
For instance, Lithium-ion
batteries cannot carry as
much energy as petroleum-
based fuels do, suffer from
low recharge period, and
have lingering safety issues.
Clearly and evidently, that
is also a transitional
technology. Significant
efforts are being made to
replace the graphite anodes
with Lithium-air batteries.
Lithium-ion batteries
comprise an anode and
cathode immersed in
Lithium solution. Scientists
are pondering at replacing
the graphite anodes with
silicon ones, which will
boost the battery’s lifetime
by 30 to 50 percent. Now, a
Korean team of researchers
have proposed an unusual
source for that silicon – rice
husk.
Rice husks are
approximately 20% silica by
weight. Silica is the similar
material that constitutes
sand. For a third of world’s
population, rice is the staple
crop; more than hundred
million tons of rice husk
piles up. Since, the
technological breakout
happened has not been
confirmed, rice husk will
invariably be recycled into
animal feed. The silica that
comes from the rice husk is
prearranged in a nano-scale
structure, because of which,
repeated cycles of swelling
and shrinking will not cause
the silicon to fall apart. It is
a known fact that silicon
expands more than 300
percent and then shrinks
back down as charge goes
down.
It is not the first time
researchers have looked
upon rice to reproduce
silicon. Being durable and
flexible, silicon is expensive
to produce, but rice husk as
the alternative for graphite
anodes has those properties
naturally. Rice silica forms
the outer covering around
the kernel so that pathogens
and insects cannot invade.
You might find rice husks in
your cell phone battery in
the future but there are lot
of kinks that have to be
addressed, some quite
significant. The purpose of
looking at rice husk as an
alternative was to find a
low-cost silicon source.
Positively the battery data
must be better and scientists
are spending their time on
it. Meanwhile, profits of
silicon anodes continue to
beckon. In spite of swelling
and shrinking and
difficulties of degrading
Lithium, the growth of more
energy-dense batteries still
attracts most of the
researchers. Perhaps, that is
why Lithium-ion batteries
get lots of popularity in the
field of electric rice.
