GM-VOLT : Chevy Volt Electric Car Site

This was a question I had posed early on after the car was first introduced. Engineers responded that it should be pretty quiet.

Humans have been used to driving combustion engine powered vehicles for 100 years.

Electric engines by nature do not make much of a sound. Hidden deep in the body of a high tech, well-insulated car, perhaps no noticeable sound at all to a driver in the cabin.

Of course, the Volt also has an on-board ICE-generator which will kick-in after 40 miles of driving.

This then presents a dilemma, which we’ve discussed before. Will the driver be shocked when the ICE kicks in? Will he/she be puzzled when the acceleraotr is depressed and the ICE continues to hum along at a constant RPM?

We have reported that GM might be planning to artificially program the RPMs of the ICE to give it a more natural interaction with the accelerator pedal.

Now, in an interview with Cars.com, Dave Lyon, GM’s executive director of interior design for North America, admits “One thing we’re debating now is whether an electric should make noise.”, and “We’re debating whether we can dial up noise, just like you can by adjusting the ringer level on your cell phone,”.

He alludes to the fact that the car could alert us to how many all-electric miles it has left, and notify us that the generator is about to fire up.

He says, “the car could advise that if you lower your speed by so many miles an hour, or turn the radio off or turn up the temp on the air conditioning or do all of those that you can make the 20 miles needed to get home.”

Clearly, to design a car like the Volt, many new issues have to be considered .

In our previous post, it sounded as though Mr. Tony Posawatz responded that the Volt will use a DC motor, which seemed surprising.

Readers caught that and I questioned Mr. Posawatz again..he indicated that the Volt has an A/C motor.

Sorry for any confusion.

After a lengthy and healthy discussion about costs of driving the Volt we needed to know at what battery state of charge (SOC) the onboard generator would kick in. GM was kind enough to let us know that was intended to be 50%.

The next question to arise was that once the generator started at what SOC would it stop again as the car continued to drive.

Once again GM has been very helpful and informative and tells us the answer is 80%.

So what do these numbers mean? Mainly it tells us they wish to be very conservative with the batteries. Although A123 Li-ion cells are very robust and can handle repetitive deep discharges to below 20% and up to 100% again, up to 7000 times, GM clearly doesn’t want to take any chances with this very expensive (and possibly leased hardware). By keeping it in this limited range, the hope will be increased reliability and longevity I would have to assume.

Lets see what happens when one drives the Volt.

For the first 40 miles, as we’ve discussed, the battery will drain from full (16 kWh energy) to 50% (8 kWh), this 8 kWh will cost you roughly 85 cents in electricity. If you drive that distance or less, NO GAS.

If you keep driving, the generator will start. It will generate 53 kW of electricity. It needs to restore the pack by 30%, which is 4.8 kW, that would take ~5.4 minutes if the generator was only charging the battery. But at the same time, as the car continues to drive, the battery would continue to drain, so the generator would have to run longer.

GM estimates that in this condition, the combustion engine would provide 50 mpg efficiency.

From what engineering experts in the PHEV/EV field tell me, the battery pack, electric engine, and generator are all on the same bus (not yellow or greyhound folks), which means that one can have current flowing into the battery from the generator at the same time it is leaving to run the powertrain.

This is great stuff, and an engineering process never before witnessed by humankind. Let’s hope it works.

In the coming weeks GM will have the Volt “mules” (cobbled-together, rough and ugly engineering experimental prototypes) up and running with the first gen A123 packs (and CPI). Then these issues will be testable under driving conditions.

Right now, as per Rob Peterson of GM, “the engineers are still working out the optimum charge cycles and control systems”. As per Bart Riley of A123, “The key will be to achieve the life target for the battery across the all operational requirements (temperature, cycling, storage, SOC range)”.

Remember folks, you just can’t get this stuff anywhere else!

We have some new and unsubstantiated information from anonymous sources that GM has decided to remove E85 capability from the Chevy Volt’s on-board internal combustion engine/generator.

One of the promotional points of this concept vehicle when it was first announced was the E-Flex system. The “E” stands for electricity, we understand the concept of the electric motor running on powerful batteries. The “Flex” stands for the fact that the energy both batteries and motor are supplied with could come from various or “flexible” sources. Of course, the engine could run on regular gasoline.

However, the Shanghai Volt concept showed us that the car could run on a hydrogen fuel cell. Other possibilities for the combustion engine included diesel, biodiesel, or 85% ethanol (E85).

We have already heard from Bob Lutz, due to restrictive standards in the U.S., GM would probably not bother putting diesel capacity into the Volt’s engine, after all, most drivers of the car would be going in electric only mode.

Now our sources tell us that GM will also be nixing the capacity to use E85 as well.

This shouldn’t surprise us too much. An engine requires special engineering to handle the very corrosive ethanol. Also, many experts believe the reason for Flex-Fuel vehicles (FFV) at all is to allow car makers to to reduce their CAFE requirements, because the reality is few of these cars actually use ethanol anyway. Try to find E85 at your local gas station.

Since the Volt gets astronomical gas mileage (approaches infinite mpg for the first 40 miles), the engine is just for generating electricity, and since the batteries are adding so much cost to the car, it seems like cutting E85 for the first generation Volt is probably a good business decision.

Remember, you heard it hear first!

What do you think?

[UPDATE: THIS REPORT WAS LATER FOUND TO BE FALSE - ANONYMOUS SOURCE WAS WRONG]

We have been discussing the cost of operating the Volt. In particular I have focused on what the electric cost will be to drive the first 40 miles without gas (or E85). We knew the battery holds 16 KWH of energy, but it hasn’t been clear how much of the battery would be discharged by the end of the first 40 miles of driving. We didn’t know at what battery power level the on-board combustion generator would kick in. Commenter’s here and myself have given our best guesses…

Well it’s official folks, I have heard back directly from GM sources, and the answer is 50%!

This is big financial news and very cool. It means that the Volt will only requre 8 KWH of power to drive the first 40 miles.

This translates to a cost then of 8 X 10.65 cents (U.S. avg) or $0.85 to drive those 40 miles!

It also means, if you wanted to, you would only have to generate 8 KWH of solar power to charge the car. That’s five 200 W panels getting 8 hours of sun.

GM spokesperson Rob Peterson also points out that the average commuter who drives 40 miles per day uses 500 gallons of gasoline per year. Multiplied by every user of the Volt, if the car becomes widely adopted, U.S. gasoline consumption could be decreased substantially.

Today has been a very productive one when it comes to news about the Chevy Volt. I had the opportunity to discuss these and other issues with Mr. Nick Zielinski who is the Vehicle Chief Engineer for the Chevy Volt. The full audio podcast follows below.

First of all, Mr. Zielinksi was able to help clarify what the new A123 contract represents. GM is continuing to work with both A123/Continental and CPI/LG. The “horse race” as he calls it to make the better battery pack is still on. One system has not yet been chosen over the other, and the winner is still expected to be announced in June 2008. What is new is that GM will now work as a much closer partner with A123, and be more intimately involved in Li-ion cell engineering. This partnership will allow GM to have proprietary access to the cells and their engineering, allowing for better final production of electric cars.

Mr. Zielinksi told me that an actual working model of the Volt is currently being built and tested in the laboratory. He agreed that working battery pack prototypes will be coming from both battery teams this fall. Interestingly, it is expected that different test versions of the Volt will be built, each with different battery packs from the two manufacturing teams. He also told me that a decision has been made to use liquid cooling (and not air) systems for the packs.

In terms of road testable models..expect the first ones before the end of this year!

He noted that GM if very pleased with the public appeal the car has and will try to keep the final production model as true to form to the prototype as is possible. He cant be sure of the name staying the Volt, but notes that he’s not the one to ask! The goal of a full mass-produced production car in late 2010 is solid.

We also discussed the issues of heating and AC and how they may affect battery life. Mr. Zielinksi indicates that thermal regulation as its known will be a significant challenge, and that the 40 mile range is predicted with the A/C off. 40 miles remains the current target for all-electric driving, but future versions will likely have more range.

All in all this car is happening at a breathtaking pace. Keep posted here for all the latest, right from the source news, as always.