The
goal is a five-minute charge for any car's battery pack; a rate that
would match the time it takes to refill the tank on a gas-powered car.
Published June 8, 2012
Engineers at Hydro-Québec’s research institute in
this Montreal suburb say they can recharge a lithium-ion battery cell
in just one minute.
That speed is the current state-of-the-art for solving one of the big
problems with electric vehicles — how to cut the time it takes to
re-juice a depleted battery.
The best fast-chargers now promise to do that job in about 30
minutes. With a 240-volt charger — the most common type — it’s hours.
But before you rush to your nearest EV showroom, you should know the
breakthrough involves recharging just a single 18650 cell, the small,
tube-shaped battery that’s used in many laptops and other electronic
gadgets, and, in a pack of nearly 6,700, powers the Tesla Roadster
electric sports car.
Still, it’s a major step in the slow-moving effort to produce batteries that can help make EVs appeal to the mass market.
The goal, says Karim Zaghib, who heads the Hydro institute’s battery
research team, is a five-minute charge for almost any battery pack; a
rate that would get drivers back on the road in about the same time as
filling a gas tank.
That level of performance is reasonably close, Zaghib says. But he
won’t provide details: The institute and its partner in this research,
the U.S. Department of Energy, have applied for patents for the
technology and they’ll reveal nothing until that’s complete, likely by
the end of the year.
Skeptics who argue it’s physically impossible to push enough
electricity into a battery to achieve a five-minute charge — several
readers have sent me detailed calculations to “prove” that point — are
just trying to pry a few secrets loose, Zaghib says with a laugh.
This development of super-fast charging is notable enough. What’s
more remarkable is that it’s just part of the groundbreaking research
being conducted at the institute — work that places provincially owned
Hydro-Québec among the global leaders in developing battery technology
for electric vehicles.
Around the world, many government and corporate labs are pushing to
develop the next-generation battery — the one that would make its
inventors rich by giving EVs the same performance, convenience and cost
as internal combustion cars. “Breakthroughs” are routinely announced,
although most come with the caution that sales to consumers are years
away.
No other utility in North America is doing anything like the Quebec
work — certainly not Ontario Power Generation, where, a spokesperson
says, “research and development is no longer part of (its) core
mandate.”
Hydro-Québec has been involved in battery research for more than
three decades and got into lithium-ion in 1995. It “wanted to accelerate
the penetration of EVs and plug-ins as soon as possible,” Zaghib says.
“We want to be recognized for helping to accelerate EVs.”
The utility has electricity to spare — 98 per cent of it from massive
hydroelectric generating stations — and would benefit from increased
demand. Its current capacity could support 1 million EVs, or one-third
of all cars on Quebec’s roads, it says.
Part of its pitch is based on the fact that, although dams on the
province’s northern rivers have had dramatic impact on the James Bay
environment, waterpower is considered a pollution-free, renewable energy
source.
“We’re charging batteries with green electricity,” Zaghib says. “This is the main reason.”
In addition, the institute expects its partners to create jobs in Quebec, making battery components based on the new technology.
Much of that success is due to Zaghib, 48, an electro-chemist who
says he dreams about EV batteries and some nights gets up at 3 a.m.,
excited by a new idea to improve them.
His cumbersome job title — director of the energy storage and
conversion department — belies the passion for his work that he
displayed during a recent tour of the research centre, a half-hour drive
northeast of downtown Montreal.
During the two hours he could spare between meetings, we raced
through research labs spread throughout three buildings, warmly greeting
any of the 37 colleagues he encountered along the way and delivering
thorough and enthusiastic explanations of the development and testing in
each location.
Trained in Grenoble, France, he has been doing battery research since
1986. Over the past quarter-century, he has published more than 130
papers and 85 patents, and edited 11 books. He was developing new
materials for lithium-ion batteries at the Osaka National Research
Institute in Japan when, in 1995, Hydro-Québec came calling.
EV batteries are made up of cells, each containing two electrodes.
One, the cathode (usually a metal compound), is positive. The other, the
anode (usually graphite), is negative. Between them is a liquid called
the electrolyte, as well as a separator (a bit of plastic material that
prevents the electrodes from touching so they don’t short-circuit).
When a typical EV battery is fully charged, each anode is full of
lithium ions. As the driver hits the accelerator, ions flow through the
electrolyte to the cathode, creating an electric current. When most have
made that journey, the battery must be recharged, which pulls the ions
back to the anode, ready to move again when power is demanded.
For sufficient power, the ions must move quickly and in large
numbers. For range, the electrodes must be able to hold a lot of ions.
For longevity, the electrodes must be able to withstand the constant
contraction and expansion as the ions enter and depart, as well as
corrosion from the electrolyte.
Current batteries produce adequate power. But, compared with
gasoline, they store very little energy, so most travel, at best, about
160 kilometres between charges. They’re also very expensive.
Hydro’s institute is trying to devise better compounds for all the
cell components, as well as new methods of applying them, to improve
performance at a much-reduced cost.
However, it doesn’t build batteries or components. Instead, it
develops materials and manufacturing techniques that others can use.
That work has led to more than 100 patents, as well as 15 licensing
agreements with companies around the world (including giants BASF and
IBM) that aim to develop the technologies into commercial products.
Typical of the hoped-for results was an announcement last month
from Focus Graphite Inc. , which owns a graphite mine in Quebec. Focus
announced it would build plants in the province to concentrate and
purify graphite, and then use the material to manufacturer anodes; with
both steps employing processes developed by Zaghib’s team. No money or
job numbers were included, and the plans hinge on market conditions and
financing, but it’s at least part of a coherent plan.
An earlier lithium technology was sold to France’s Bollore Group and
became the foundation for that company’s Bluecar, an EV used mainly in a
successful car-sharing program in Paris.
Battery research is painstaking, because each component comes with
benefits and problems. For example, those that hold more ions tend to
release them more slowly. On top of that, even a small change in a
compound or process can radically alter how the whole thing performs. So
each change leads to a whole new round of tests.
The institute gets $100 million a year from Hydro-Quebec and
licencing revenue. Part of that funding goes to battery research, where
the immediate focus is on compounds that promise more durability and
safety, as well as the ultra-fast charging.
Projects include cutting the cost of an electrolyte that doesn’t
burst into flame when the cell is punctured or compressed — but is 25
times more expensive than the current type.
It’s also working on a silicon-based anode that would dramatically
increase energy storage, and just beginning research into lithium air,
the ultimate, but extremely difficult, technology that promises huge
increases in range.
With plans for the institute to grow to 65 people by 2015, Zaghib, a
father of four, has plenty to keep him busy. He doesn’t mind.
“I love my job,” he says. “I’m not counting my hours.”
Wheels Canada
No hay comentarios:
Publicar un comentario