Marshall Miller, Senior Development Engineer
Institute for Transportation Studies, UC Davis
Ingrid Lobet: You have heard some of the praises they are
singing of this Altairnano battery, what do you think?
Marshall Miller: Well some of those attributes are actually
quite good. One of the problems about batteries in the past was that a battery
would not be able to be charged enough times in its life. In other words, it's
battery life would be too small for the lifetime of the vehicle. You would have to replace the pack.
If it's true that this battery has the life they say, then
you would certainly not have to replace the battery and that would
significantly lower the cost.
Another concern for lithium ion batteries has been safety.
In the past the concern has been that if the batteries are charged improperly,
they can catch fire. But some of the new technologies have improved on that
problem and now the belief is that fire is really much less of an issue.
So other companies are also taking out the carbon and
replacing it with something else?
Marshall Miller: Yes there are some companies that have
looked at the power tool market. And are marketing batteries for that
market. And those are the
batteries that are being looked at for the next generation of electric
vehicles.
And in our lab we are testing batteries from A123. They are being sold for power tools and
when we test them in our lab, they certainly have properties that are at least
similar to the Altair batteries. We have not tested cycle-life, but some of the
other properties, such as fast charge, are fairly similar to the claims being
made by Altair.
Ingrid Lobet: What do you think of this startup company
Phoenix Motorcars?
Marshall Miller: There have been traditionally several
problems with battery electric vehicles.
One problem is the range and that is a function of the energy density of
the batteries. Lead acid batteries, which are fairly cheap, have much too low
an energy density to be practical in an electric vehicle. In other words, for a large or mass of
batteries, you still only have 40-50 miles of range.
The benefit of Li ion technology is that its energy density
is significantly higher than lead acid and it's higher that nickel metal
hydride. The hope is with these batteries is that the weight of the vehicle
would not be prohibitive for 200 miles.
But the biggest problem I have seen with commercializing
electric vehicles is the cost. The
cost of the battery. And one
thing--with the cycle life being large, you do not have to replace the battery
pack. But still, it has been
expected that Li ion would be too expensive to be practical in commercial
vehicles--at least moderate cost commercial vehicles. So cost is still n my
mind, the outstanding factor that has to be brought down to make battery
vehicles commercialized.
Ingrid Lobet: Phoenix is relying on zero emissions vehicle
credits to be able to sell the cars at a moderate price at first.
Marshall Miller: Well that's probably true. The battery
costs and vehicle costs at low volume would be significantly higher and will
prohibit consumers from purchasing them. With credits you can bring that cost
down. And that is certainly a policy that people have felt is important for
governments, in order to push these tehcnologies
But in my mind is--once you get past a relatively small
number of consumers, when you want to get into the mass market, what will you
do, the government will not give credits for electric vehicles when they are
being purchased in large quantities, so then it would be important for the cost
to be comparable with conventional vehicles.
Ingrid Lobet: Do you believe that that the lithium titanate
represents a breakthrough or is that hype?
Marshall Miller:
Well I am not so certain. Lithium ion batteries have been around for a
while and we have tested them in our labs for at least five years now. The properties of the battery, with the
exception of cycle life, have not changed a lot. It may be that the Altair
battery haas a slightly higher power density, in other words, for a given weight, it can produce more power to the
vehicle. But the power density of conventional lithium ion batteries has been
high. The energy density has also not been a problem. They store quite a lot of
energy for a given weight, and have a lot of power for that weight. The real
problem has been the cost, and potentially the cycle life. The real issue has
been cost and to a lesser extent, the range of the vehicle, which of course is
related to battery size--weight.
The cost to me is still a major concern and in my view that
was the dominant problem why the ZEV program did not move forward in
Calfironia. Both the government and the auto manufacturers believed that
battery electric vehicles were too costly to sell on the market.
Ingrid Lobet: Phoenix has an idea where you could bury a
large battery underground at filling stations the same as fuel tanks are
buried. It could charge up at night on off-peak power and then be available
with a pump handle, metered just like gas.
Marshall Miller:
Technically, it is certainly possible. The battery packs you mentioned --a 35
kWh battery-- I see no reason why you couldn't charge that in the 10 minutes to
essentially the full charge. The
question is whether you could install the electronics necessary for that high
power and whether public officials would consider that a safe situaiton--
charging at that high power.
We do that with those currents, not quite the same power
and voltage, but at our lab we charge at very high power and we do charge
lithium ion batteries in 6-7 minutes. In our lab it's not considered unsafe,
but there may be issues in a public fueling station. It's certainly technically
feasible, certainly a possibility, whether it is practical and we will see it
in the future, is a question.
In our lab, the real question is, environmentally-minded
people see the need for a change in our oil-based transportation structure, the
question is, to what? There are four options. One is battery electric, hybrid, fuel cell, and vehicles
that use liquid fuels from bio feedstocks. The really exciting thing is WHICH
holds the most promise and which will be commercialized first, and will there
be more than one that will play a major role in the next ten years.
Ingrid Lobet:
Many people seem to put stock in the plug-in hybrid.
Marshall Miller:
I always thought plug-in hybrids had the same problem as battery
electric vehicles, their battery pack makes them significantly more expensive
and therefore possibly less likely to make major market penetration, so it has
to do with the size of the battery pack and the cost of the battery pack.
We at the Institute are looking at plug-in hybrids again
because we want to see what the costs and environmental benefits would be and
so on. We looked at these issues 6
or 8 years ago. And in my mind with the cost, it wasn't so exciting. Today it's
possible the battery technologies might have lower costs so I might have have
more confidence in that and therefore able to predict a lifetime cost for the vehicle that is
in the ballpark of a conventional vehicle and therefore potentially able to be
mass marketed.
A number of elements still contribute to the cost being
quite high.
One issue for Lithium ion batteries and other batteries for
electric vehicles is they are not produced in big volume, so we don't know the
true cost. We can call the manufacturers and ask them, but most likely they
will give us an inflated cost because they know they will not be selling them
in high volume, we don't have a market where these are produced in high volume.
Ingrid Lobet: What if there were an angel, someone like a
George Soros were to build a battery factory?
Marshall Miller: Well certainly the cost would be lower,
how much lower, I'm not an economist, I don't know. The hope is to get the cost down to a factor of two higher
than conventional lead acid batteries for the same energy storage. Even at that
cost, the cost of the battery pack is fairly expensive, like $6,000 dollars for
a vehicle that would go 100 - 125 miles or so.
The question, as you bring the price down, where does it
plateau? How low can you get it, low enough to be mass marketable? I think that
is something no one really knows at this point.