GM-VOLT : Chevy Volt Electric Car Site

Frank Weber is GM’s straight-shooting vehicle line executive of the Volt program. I had the chance to ask him what was happening with mule development.  At this point there are 35 or so developmental mule vehicles.  Mules are early prototypes that have the full Voltec drivetrain but a borrowed interior and exterior.  Within days the engineering freeze on the first true Volt prototypes or integration cars will occur.

What is the current status of the mules, since you are done with this phase, and where are they in the testing process?
Actually what is happening is we have done all the testing as planned last year. We have been using the winter for winter tests. You are counting in summers and winters. This is a very important phase to test everything under very cold conditions and this is what has been happening now.

So are you still figuring out the control algorithms and computer code?
This is all the standard procedures in a car and you know what to do and we have all those controls incorporated into the cars. But now what’s happening is the true development work that you say OK this is the temperature of the battery, and this is the temperature of the system, and this is what happens when you are plugged in, etc.

There are parameters that we call calibration, you have the basic software functionality on those cars defined, and then we start to calibrate it looking at the temperature and when to we start it, what is the true power of the battery at a certain temperature , etc.

How do you know how the batteries are performing in the mules, and how can you extrapolate forward to know that you hit the right sweet spot to make the battery last 10 years?
What you know is what the behavior is for the cars that we are testing, and then you make an assumption for how a component will behave over time and how it will behave under the same situation in several years.  This is what we call accelerated testing. This gives you some indication of durability.

The piece that is tricky and interesting about the battery is to do a really accurate extrapolation of the true behavior. For a mechanical part this is very simple. For a mechanical part you can replicate its lifetime and find out when it will break.

The battery is electrochemical and its more difficult to make those extrapolations. This is part of the learning we have to do, battery learning between the battery supplier LG and us. By the way this is still the element of risk. This is also why we are unable to get the car out any sooner. It is those things that have to be developed now with the components that are representative of the production vehicle.  There is no way to do this any faster.

Have you started to build the integration vehicles yet?
No this is a different phase. Mule cars are now completed and have been since last year. They were all built on time. Whats happening now is those mule cars are now being tested up until the middle of 2009 and then they are replaced by the next generation of vehicles which are called integration vehicles. It takes a couple of weeks to complete the build.

Are the internal parts on those more refined than the current generation.
Yes, always. Whats true in the development is if you find something you might make a small adjustment to it to improve it. Its an updated version of those components.

Are you going to take those integration vehicles out of the test grounds and drive them around the real world?
Normally you have to be a little bit careful, but since we’ve shown the world the production version we can in principle take them wherever we want.

Will you?
Only if it is value added. There are a couple of interesting streets in the world where development insight is really generated. Then it might make sense to take then out there. By the way the current mule cars are being taken out on the public roads.

People who follow the Volt development closely know that GM has about 35 mules clad in Chevy Cruze bodies.  These have been undergoing extensive continuous daily testing for months.  By the summer we will see the arrival of the first full Volt interior and exterior prototypes, and likely begin to see public test drives.

I had the chance to ask Jon Lauckner who is GM’s VP of global program management what has been happening with control development on the current Volt mules.

GM has already “laid out all of the concepts that we want to use and written a lot of the preliminary code,”  said Lauckner.  He notes the car’s behavior “has to be software driven” and that all the code has already been “put into our mule cars and we’re evaluating and testing it.”

GM has apparently figured out most of how the vehicle will behave. “I would say that conceptually we’re most of the way there if not all of the way there,” in terms of behavioral programming said Lauckner, “but there’s a lot of work to be done still to make sure that the whole thing operates seamlessly.”

Lauckner feels it is imperative GM makes this car absolutely perfect.  He said “we need an experience where people say ‘Wow’ this is really something special. These guys have put a lot of thought into the technology, a lot of thought into the interface between me as a driver and how the car behaving that it tells me the kind of information I need know when I need to know it and that it operates very intuitively.”

“That’s the level of refinement that requires very little explanation for people to understand exactly what going on,” he said.

He says having the car operate completely intuitively and with very little driver explanation is “the reason why we do development.”  He says GM really has to “love this thing a little bit to make sure that you not only get it that it actually works but you get it working in such a way that its completely intuitive.”

As to why this development process seems so long to us he said “we need the time with the car and we need the time over a wide variety of conditions to simulate certain things, so that we can see just exactly how the car is going to behave and what sort of information the driver is going to get to make sure everything works in as seamless a way as we can possibly make it.”

Now that electrification has begun to take hold, the roles will be reversed from present day hybrids.  Instead of a small electric motor assisting the main gas engine, the gas engine will take a backseat.  This is well illustrated in the Volt where the gas engine simply waits until its services are needed only if the battery gets low, a time that in many cases will rarely if ever happen.

Because of this limited functional requirement, gas engines will become increasingly simpler and smaller.  Eventually all of the advanced technology cooked into today’s combustion engines to make them adequately powerful and efficient will no longer be needed.

For the Chevy Volt according to John Bereisa, director of advanced engineering at GM, “All we need is 67 horsepower, enough to maintain the batteries’ charge when the car is cruising at highway speed.”

He explains how the choice for the Volt’s combustion engine was arrived to: “Since there wasn’t time to design an engine from scratch, we looked for the smallest existing engine capable of supplying 67 horsepower, which turned out to be G.M.’s Family Zero design used in Europe, Asia, Africa and the Middle East.”

He also tells us the Volt’s engine when in use will run in a target range of 2000 to 3000 RPM.  He notes “When you map an engine’s power versus r.p.m. versus fuel consumption, the resulting chart looks like the Rocky Mountains. In conventional cars, you’re driving all over that map. But in the Volt, we’re able to keep the engine operating in what I call its happy valley, where it delivers the power that’s required while consuming minimal fuel.”

Bereisa hints at what GM is planning for the Generation II Volt engine.  He says “We’d select a smaller displacement engine for the future, probably less than 1 liter,” and “We’d position the catalytic converter and route the coolant lines to minimize heat losses.” He adds not surprisingly “the engine for the next Volt will definitely be as simple and as light as possible.”

And so the gas-powered combustion engine shall ride off quietly into the sunset.

Source (New York Times)

A Chevy Volt article appears in the Washington Post today.  Questioned is whether the Volt will be sufficient to resuscitate GM or whether it is too expensive and its competition too fierce.

An Obama administration official gave the first word of what the Task Force on Autos though of their Volt prototype test drive, “The Volt certainly shows promise, but it is no panacea for what ails GM in the near term.”

At a price possibly close to $40,000 it is proposed that the car is too expensive for most people. Not mentioned is the $7500 tax credit already approved for the first 500,000 buyers of the car. Bob Lutz is quoted as saying “Over time the costs will come down and be competitive with conventional cars, although right now that’s not the case.”

Lutz is also quoted as saying Cadillac could have been the first brand to get this technology.  He said “Doing it in a Cadillac would have made it financially easier to do, but on the other hand we wanted something that’s boldly applicable, Our big 5 million-unit global path is Chevrolet. With the Volt we can sell it around the world.”

My favorite part of the report is how it is mentioned that the Volt has “inspired a legion of fans.”  Apparently there is a popular Volt news website with over 47,000 people signed up as being interested in buying the car.  Id love to check it out, but the url wasn’t mentioned.

Source (Washington Post)

On March 11th, the world heard about a new breakthrough in lithium-ion battery technology. Researchers Gerbrand Ceder and Byoungwoo Kang created a new technique that gives lithium-ion batteries a 100 fold increase in power density. These new batteries when moved from lab to factory could allow charging at 100 times the speed and release of 100 times the power of batteries in use today.

This technology may apply well to small batteries such as those in a cellphone that one could charge in 10 seconds using typical household current. To recharge an electric car using such a battery at maximum rate, though potentially only taking 5 minutes, would require much more massive currents than whats found in the typical household.  But it could enable the possibility of rapid public charging stations.

In general, electric vehicles (EV) need batteries with high energy density so that they are light and compact and can store many miles worth of driving energy. Power density is also needed to a lesser extent to release sufficient bursts of energy for acceleration and hill-climbing.

Hybrid (HEVs) batteries need better power density to assist the gas engine in high power situations, but energy density is less important. Thus, an automotive battery is usually described in terms of power to energy ratios. A high PE is good for HEVs, EV requirements are lowest, and PHEVs are in between.

GE automotive battery expert Herman Weigman told GM-Volt.com of this new breakthrough “a battery of such high power density is only of interest to HEV’s (and military pulse power applications), where you need to install power capability over a 1~30 second time frame.” He was less enthusiastic about its use in EVs noting “an EV is only interested in Energy Density (Wh/kg and Wh/Liter) and the cost of that energy ($/kWh)… they will never use the (new) technology.”

I was able to obtain a very brief Q & A with Byoungwoo Kang, the key MIT scientist who created the breakthrough battery:

What type of energy density do your cells have, and are they superior in that regard to standard LiFePO4 batteries?
Our development is related to increase power density, not energy density. The energy density of our material is similar with standard LiFePO4 batteries.

What is the total number of cell cycles you have achieved with these?
Under Lab conditions, we tested the cell for at least 100 cycles. At that time, there was no capacity fading.

Do you see these cells being better for HEV or EV automotive applications?
Our strategy sharply increased the power density of the LiFePO4. Also, LiFePO4 has great thermal stability (No Explosion). These properties makes our material more likely feasible for HEV or EV. However, if you see these two properties are more important than others like energy density, our materials can (be used) for portable devices.

Norwegian electric automaker Think has recently been on the brink of bankruptcy but was rescued by US lithium-ion battery manufacturer EnerDel.

Now they are coming back from the dead with new plans to travel across the Atlantic.

Today they announced plans to build an electric car manufacturing plant in the United States. The company is in discussions with eight states including Michigan to build the plant which will begin production at 16,000 per year and be able to ramp up to 60,000 per year.

Think CEO Richard Canny said “We see ourselves playing a small but potentially growing role in re-inventing the U.S. auto industry by bringing back new manufacturing jobs to the U.S. to replace internal combustion engine vehicles that are expensive to operate and maintain with clean, efficient electric vehicles.”

Think is working with both A123 and EnerDel on developing lithium-ion packs for the cars and runnig developmental prototypes exits. They will also be applying for advanced vehicle technology loans from the DOE.

The initial vehicle will be the 2-seat Think City that has a 112 mile electric range and a top speed of 62 mph.

The pricing is not yet announced but the goal is under $20,000 minus battery lease and with incentives. U.S. production is expected to start in 2010, with the first-year volume of 2,500 units being available to pilot and demonstration fleet projects.

The Think OX is the 4-door hatch model which would come later.

Source (Th!nk)

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