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Battery Breakthroughs — Myth or Fact
The battery is increasingly seen as a green energy solution
to liberate society from the dependency of oil. While this crusade is noble and
right, the battery has not yet matured to assume this obligation. Pushing the
boundaries reminds scientists of the many limitations in the battery being an
electronic chemical power source that is slow to fill, holds limited
energy, runs for a time like a wind-up toy, and has a defined life span of only
a few 100 cycles before it becomes a nuisance.
In an age where surprise developments flash before our eyes almost daily, the
battery seems slow in maturing. Improvements achieved since the
commercialization of lithium-ion in 1991 by Sony are pale compared to the vast
advancements in microelectronics. Compared to Moore’s Law, where the number of
transistors in an IC doubles every two years, Li-ion only gained eight percent
capacity per year during the last two decades. This has slowed to five percent
but the good news is a cost reduction of eight percent per year.
Progress is being made but not without roadblocks. Lithium-air proposed in the 1970’s with a theoretical specific
energy resembling gasoline is delayed due to stability and air-purity issues as
the battery “breaths” oxygen from the air. The promising lithium-metal introduced in the 1980s still grows dendrites, leading
to possible violent events if an electrical short develops.Lithium sulfur may be close to commercialization but scientists must
still resolve the short cycle life. The redox-flow battery promises a solution for large battery systems by
pumping fluids from external tanks through a membrane that resembles a battery,
but the system suffers from corrosion.
There is a glimmer of hope to increase the energy density of Li-ion by coating
the anode withgraphene, a layer that is only one atom thick. This is said to
quadruple the energy. Immerging battery technologies will take four years to
commercialize, and there are no heavy lifters or a homerun.
The Joint
Centre for Energy Storage Research (JCESR) is more optimistic.
The organization gathered the brightest minds from US national laboratories,
universities and private enterprises to improve the battery. With a grant of
$120 million from the US Department of Energy, JCESR wants to develop a battery
that is “five times more powerful and five times cheaper in five years.” They
call this the 5-5-5 Plan. Until now, battery development has been methodical
and adding fertilizer might boost the growth for a time, but too much can
poison a tree.
Toyota is also in the race for a new battery; it will be called the “Sakichi
battery” after Sakichi Toyoda, the inventor of Japan’s power loom. (The surname
Toyoda is spelled with a d.) Sakichi Toyoda is often called the father of the
Japanese industrial revolution and it is said than in 1925 he promised a
yet-to-be-claimed prize of 1 million yen for a storage battery that produces
more energy than gasoline. To qualify for the price, the Sakichi battery must
also be durable and quick to charge. The price has not yet been claimed.
Consumers are generally satisfied with battery performance in
portable devices, but the EV calls for a higher demand; cost and endurance will
determine the long-term success. It’s as if the EV sets the threshold of how
far the battery can go.
It makes little sense to use batteries to propel trains, ocean-going ships and
large airplanes. Batteries are simply too heavy. If all engines and the fuel in
an aircraft were to be replaced with batteries, the flight would last under 10
minutes in duration before the fuel was exhausted. Competing against fossil
fuel with a net calorific value that is 100 times higher than the battery is a
challenge. Conversely, petroleum cannot touch the battery that is clean, quiet,
small, and has an immediate start-up with the flick of a switch.
