What are some of the safety issue of this car, are they different than standard cars, are you going to have to do different kinds of crash test safety?
We already have a standard program of very rigorous tests. Well run crashtests of all sorts, because frankly were looking to sell this vehicle globally. So we know that we’ll have to meet all the U.S. regulatory requirements for crash, we have to meet all the European regulatory requirements for crash, the one’s that exist in China and all the other countries around the world. So we are going to run a huge series of tests on tis thing which is pretty much what we do for any passenger car or truck that we build.
Clearly the fact that we have a battery pack running down the middle of the car we will definitely pay attention to whats going on in that particular area. But thats not such a bad place. If you want to put a battery somewhere thats not such a bad place to put it, because its quite well protected with a lot of crush space around it.
So again too early to talk about how all thats going to play out but clearly were building simulation models in that area too, and we know that we have to take care of all this stuff. We have to look after all of the aspects of safety; charging it, crash, you name it.
Is the car planned to have a 50:50 weight balance as has been quoted?
Maybe they (the journalist) talked to me and got slightly off track, but heres what I would say, maybe we can get this one accurate. Typically a front drive car has upwards of 60 to 65% of its weight on the front axle, OK, because its got a drive system in the front and an engine, and a passenger compartment, but relatively unladen in the rear so they tend to be more biased with front end mass. Now I’ve got a sizable battery pack, maybe 160 kg, maybe a little more, maybe a little less, and I’m going to put that right in the middle of the car. That will most certainly change the front to rear weight distribution, right? So the whole car will weigh more but the weight distribution will be less mass on the front axle as a percentage of the total. Because Ive taken and Ive put this relatively large mass right down the middle of the vehicle almost dead in the middle of the two axles.
Where will the combustion engine sit?
In the motor compartment in the front where it always is (together with the electric motor). They will both be in the motor compartment. So again if you think about it thats the kind of mass and kind of location that we have in our front drive vehicles, so again its probably going to be a vehicle that has 60 to 65% of the mass on the front axle. But then I put this mass in the middle and although the vehicle will weigh more overall the mass distribution will be better.
So not necessarily 50:50?
No, not 50:50 but clearly shifted in that direction.
This entry was posted on Monday, January 28th, 2008 at 6:00 am and is filed under Engineering, Original GM-Volt Interviews. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.
Jan 28th, 2008 (6:55 am)Thanks Lyle,
The new look of the site is fine and more readeable. Where may I find the waiting list count ?
We now have an estimation of the battery pack weight.
An ANR26650M1 cell weights 70grs, has 7.6 wh of energy, and gives 3.3V.
See :
http://www.a123systems.com/#/products/p1 or http://cactus-modelisme.com/Documents/A123.pdf
Can anyone make something with those data ?
Well, I propose : 160 kg means 2,285 cells that produce togheter 2,885 * 7.6 wh = 17,366 wh or a little more than 17Kwh.
Seems close to the original data but I am not an engineer, …
Jan 28th, 2008 (7:56 am)Excellent questions as usual, Lyle. Nice new look.
Some feedback on the new look:
1) Putting the “quote” feature back would be wonderful.
2) Please, please, please, put comment numbers in. It really makes
referencing so much easier.
3) I agree with Jean-Charles, the waiting list count needs to show
prominently.
Thanks. Rashiid.
Jan 28th, 2008 (8:05 am)*shrug*
Not a big fan of the site revamp. Too much going on, seems far too busy. Perhaps it’s me getting old.
I was under the impression that each (back) wheel had its own motor. How is that both motors are under the hood? Maybe I haven’t been paying enough attention.
Jan 28th, 2008 (8:21 am)Lyle: Great job !
This is the first order of business when I come into the office and log on.
Rashiid:
I know that Texas is a long way from where you are at, but I hope some day to shake your hand and say howdy to you and other VOLT supporters. I really look forward to our first VOLT rally.
Jan 28th, 2008 (8:37 am)Brian, the car will not have a motor for each rear wheel, you may be thinking of the Volvo EV concept.
Jan 28th, 2008 (9:23 am)Early reports did have the volt on a virgin chassis with traction motors at all or 2 wheels. Now we have a car taking shape on the cobalt platform with a single drive a/c motor on a probably reworked trans axle assembly. To keep costs down, which is great..The concept car looked like a 100k car but now were closer to the real deal that’s ok with me!! Because as I’ve said in other posts if the car comes in at 25plus to start all you’ll see is prius sale’s take off more..especially if the volt turns into a cobalt ev with a back-up generator and fancy bodywork…good luck gm
Jan 28th, 2008 (9:24 am)I also like the #’s on the threads .If thats not doable with Lyle’s new format perhaps we can start numbering our own posts according to the last one we read before posting. I sure we will get a few with the same # but it would still help.
I often have to make note of where I was on a post in order to finish reading later as we get 60-70 replies on a single post before I get home from work!!
Jan 28th, 2008 (9:57 am)I just love this blog.
I have a question? If Volt is going to use batteries for the first 40 miles, what is going to heat the car?
I know cars are passively heated by the excess heat for IC engine. Anybody know?
Ash
Jan 28th, 2008 (10:06 am)Post #8
Good idea, bill …I’ll start the ball rolling.
Jan 28th, 2008 (10:08 am)Post #10 (corrected)
OOOps …Ash beat me to the draw.
Jan 28th, 2008 (10:36 am)Post # 11
*Ash #7*
I have read that they will be liquid cooling for the battery but I’m sure they will have to bring they temp up some more to heat the interior of the car. there would have to be some friction heat loss somewhere they can capture rather than use battery power to heat an element.
Jan 28th, 2008 (10:47 am)#12
I think we have read before that there will be electrical heating and AC.
And Jean-Charles, #1: Don’t forget that some percentage of that weight will be packaging, cooling system, etc.
Jan 28th, 2008 (10:53 am)I heard it was some kind of electric exchanger Heat you turn it on it runs like hair dryer only bigger. Cold air it reverses polarity of the exchanger thus it gets cold and that’s the A/C.
Jan 28th, 2008 (11:01 am)Post #14
Re: battery heating… my guess is GM will use electric strip heaters & heavily insulate the battery like we do on spacecraft. High-quality insulation can reduce the amount of energy to keep the battery warm, even in very cold climates, to surprisingly little. (The exterior of a satellite can be around -300 degs & they all have batteries that must be kept MUCH warmer).
I’d also guess that the heat pump GM will undoubtedly use for the passenger compartment can also be automatically activated for those fairly infrequent times the battery needs cooling, and that they’ll route a water/ethylene glycol mix or something similar thru the piping incorporated in the battery pack for cooling purposes.
Jan 28th, 2008 (11:06 am)Post #15
Slightly off topic, but Lyle has recently placed a lot of very high quality photos on the sire’s “Gallery”. The following link is a Volt concept cutaway showing more details than I’ve seen anywhere else….
http://www.flickr.com/photo_zoom.gne?id=2173007580&size=o
Jan 28th, 2008 (11:36 am)Post #16
Tom M. #4: Someday we will meet. I look forward to the first
Volt rally also.
Jan 28th, 2008 (11:53 am)Post #17
Brian M #12
OK Brian, in fact doing the computations, i tought of that and also 70grs is the weight of the core cell (that means I think without the protection envelope). So If we take the assumption that 16Kwh is what the battery pack must produce, we must count on 2,105 cells instead of 2285. That makes 147 kgs of net weght and we are left with 13 kgs for what is left (cooling, regulation, …)
But perhaps the ANR26650M1cell from A123 is not the one used in the battery pack. Does anyone have an info on that topic ?
Jan 28th, 2008 (12:23 pm)Post #18
Am I correct that the Volt will be front drive only? From the image in post #15 – it looks this way … and I assume that it would be cheaper to build.
P.S. I like the new look – but as others have said: we NEED post numbers!
Jan 28th, 2008 (12:45 pm)Post #19
Yep, it’s FWD …the result is 1) the range is maximized by putting the battery where the drice shaft for an AWD would be, and 2) the car has bucket seats & a console in the back seat. I call it a “4-door sport sedan”. Neat, huh?
Jan 28th, 2008 (12:47 pm)Post #20
PS: An EDIT or REVIEW function would be nice too, since we techno-weenies don’t spell too well!
Jan 28th, 2008 (12:56 pm)Post #21
Nasaman #20, this techno-weenie uses Firefox, which has a built in dictionary.
If I’m paying attention, it tells me what words I typed / misspelled incorrectly.
Jan 28th, 2008 (1:12 pm)Yes – Front wheel drive with a single electric motor driving the car. There is no transmission, but a differential/axle assembly to deliver power from the electric motor (which is in the engine compartment along with the gas motor) to the front wheels…
Jan 28th, 2008 (2:06 pm)#23 (I think)
nasaman, #15:
Very cool cutaway. Thanks.
Jan 28th, 2008 (2:07 pm)Lyle
This new look for this website is not that attractive and hard to read.
I think you might need to go back to the old version.
G
Jan 28th, 2008 (2:26 pm)#25
I like the older version that numbers our comments for us, and for the crappy eyesighted ones, the names of who typed the comment are almost impossible to read. On another note, I am really looking forward to meeting a lot of regulars here when the first get together is arranged. Hopefully before we get our own volt, then definatley for many years after. Two more years will be too long to see the people behind the names and great comments I read every day.
Jan 28th, 2008 (3:19 pm)#26
A Reuters article on Yahoo this morning reports that Chrysler is offering $100,000 buyouts to reduce its Detroit area workforce by 10,000 jobs. The article also notes that GM announced earlier in January that it was offering buyouts to 46,000 workers. It also reports that Ford is offering buyouts to 54,000 workers.
Remember when the Monday Night Football games used to get within a few minutes of the end, and Dandy Don Meredith would break into his rendition of “Turn Out the Lights, the Party’s Over”?
Jan 28th, 2008 (3:38 pm)FWIW I preferred the old style as well. It seems as though everyone is shouting with the large type and it can be difficult to follow esp w/o numbered posts.
BTW did anyone catch the bio/electric car episode on TWC’s Forecast Earth w/Natalie Allen? Pretty good show.
Jan 28th, 2008 (4:14 pm)I liked the old style better as well.
Jan 28th, 2008 (4:16 pm)This new format does seem to load faster though.
Jan 28th, 2008 (4:36 pm)Post # 30
It has been loading faster for the last 2 weeks or so..
I’m thinking they are either giving Lyle more bandwidth, or he is
on a better server.
Strangely, we haven’t really heard from Lyle today concerning his
new layout.
Lyle? You there?
Jan 28th, 2008 (4:40 pm)Electric cars almost have to be FWD or AWD. The reason is regenerative braking. 80% of your stopping power comes from the front wheels. To recapture that you must have a motor on the front wheels.
(I liked the old comment style as well. The new ones are too wide. It’s a fact that wider text is harder to read… hence thin columns in newspapers and magazines.)
Jan 28th, 2008 (4:50 pm)Is it good to brake on the front wheels only? Regen needs to kick in before the friction brakes. Then with greater demand, the friction brakes start, with front disk, and rear drum.
I had thought maybe there was a regen generator on the rear wheels. Maybe not.
Jan 28th, 2008 (4:50 pm)I bet you actually do most of the braking on front. thats why some cars have front disc.
Jan 28th, 2008 (5:00 pm)Exactly. The reason that 80% of your braking comes from the front is that the car’s momentum keeps pushing it forward. For a long time most cars came with front disc/rear drum. Now that most cars have 4-wheel-disc, the rear discs tend to be much smaller and you may notice that they wear out much slower.
Of course you don’t brake on only the front wheels, you want to have some redundancy.
Regen brakes can work with friction brakes simultaneously so there’s no concern about wasting energy.
Jan 28th, 2008 (5:03 pm)Hey guys
I am receptive of your feedback on the new format. My goal was to get a lot of the important older posts onto the front page, which I think we’ve done. This will help out new people, it wont matter as much to regulars who have been following closely.
The site is also wider now which is a benefit.
I am not happy with the small font of the commentators name and lack of numbers either, I have asked the designer (this is a professional custom design BTW) to fix that..I hope he will soon.
Anyway its a work in progress so bear with us. I will take all feedback into account.
Furthermore the forum is supposed to move to a much upgraded and integrated version soon with all of the older posts and users ported into it.
Consider this GM-Volt gen 2.
Jan 28th, 2008 (5:27 pm)Post #36.
Thanks Lyle for the update.
Jan 28th, 2008 (6:01 pm)Lyle,
Thanks, Just wanted to add that I was also confused by the poster’s name appearing below the post. This is not standard for any site, especially the very popuar V-bulletin, so new users may be a little confused.
Keep up the good work.
Jan 28th, 2008 (6:22 pm)New look , and new chages I see. Well, I just need to learn how to navigate it , I am a little lost.
Jan 28th, 2008 (6:24 pm)Where is the waiting List?
Jan 28th, 2008 (6:35 pm)Regen brakes can work with friction brakes simultaneously so there’s no concern about wasting energy.
Well, I agree with all but this. As soon as you start dissipating heat to slow down, you are wasting energy. You only want those to kick in if you must stop faster than regen can handle.
Now I am speaking theoretically. As an armchair theorist and engineer….There may only be so much you can get from regen.
But I want to hit my brakes gently, and not have friction brakes kick in.
Jan 28th, 2008 (7:24 pm)Just my 2 cents on new design- it seems like there’s a lot of wasted space on the top right of every page (about 6 square inches of non-functional beige).
Also – could we have the person who’s posting have their name be before their text?
Concerning the interview part 4, it’s interesting he quotes 160kg as a rough battery pack weight- does that hint at a weight reduction goal for the prototypes? The first prototypes from Compact Power weighed 200kg, or 80Wh/kg gross energy density. 160kg would put the gross energy density at 100Wh/kg.
re:Jean-Charles, they’re not using the M1 cells, but a custom flat cell design. So similar chemistries (at least for A123/Conti), but larger, more stackable cells.
Jan 28th, 2008 (8:06 pm)Friction brakes will only kick in if the regen brakes are overwhelmed or the battery is already full. Well, they may also be activated every week or so to keep the rotors from rusting up, and if the car has a system for sensing rain, it may periodically activate the friction brakes to keep them dry in case of an emergency stop.
It’s said that unless you do a lot of hard stopping, the brakepads in a Prius should last the life of the car, to give you an idea of how much regen brakes are used vs. friction. And the Volt will have heavier-duty regen braking than the Prius by way of a bigger motor and battery.
Jan 28th, 2008 (10:33 pm)On the subject of brakes, unless your driving some huge gas sucking monster from the 60′s you have front disk brakes. The brakes are engineered to stop evenly, applying even pressure at all 4 corners. They even coil the front brake lines to ensure all 4 lines are the same length. However the laws of physics come into play and the front tires do take up most of the stopping power.
Jan 28th, 2008 (10:59 pm)It is my understanding that the vehicle will not use the ANR26650M1 cell, or even one of the larger 32 series cells, but a newly developed prismatic cell with improved performance and a more easily packaged form factor.
Jan 28th, 2008 (11:05 pm)Here is the link to the article:
http://www.autobloggreen.com/2007/12/03/evs23-a123-shows-off-new-cell-design-for-volt-battery-pack/
Jan 28th, 2008 (11:28 pm)I have a suggestion for the new design (if it hasn’t been mentioned yet).
I like the ability to quote other posters without having to copy and paste.
Jan 28th, 2008 (11:57 pm)Post #47
Hey Tony, not to detract from the point of your last 2 posts that the A123 cell for the Volt is a new design, but did you notice that the link you give to autobloggreen.com credits gm-volt.com as its source?
ATTN EVERYBODY:
Please number your own posts until self-numbering is restored.
Jan 29th, 2008 (3:10 am)Post #48
I may have a very basic misunderstanding. Please let me know if I am wrong.
I thought regenerative braking happened when the propulsion motor became a generator when electricity was no longer fed to it but the vehicle was still moving. If more braking was needed, the friction brakes were used. I get the feeling from the above comments that the actual brakes are different and generate electricity at the wheels, not via the motor. Please let me know which is correct.
On the matter of friction brake wear, Prius taxis get about three times the mileage before brake pads need to be changed, compared to conventional taxis.
Jan 29th, 2008 (7:08 am)Post #49, reply to Bill, post #48
Bill, you’re halfway there. When the electric motor is off, the crankshaft can spin freely. This is the equivalent of putting the car in neutral.
If the electric motor is set up to produce a constant magnetic field on the crankshaft, the rotation of the crankshaft is converted into electrical current. The stronger the field, the “harder” it is for the crankshaft to spin, and the more current is generated.
This means the brake pedal will basically control the strength of the field. Pressing harder will slow you down faster and produce more electricity. If the regen “brakes” are maxed out or the battery is full, the software will activate the friction brakes to provide extra stopping power.
Jan 29th, 2008 (9:40 am)>> When the electric motor is off, the crankshaft can spin freely.
ASSIST hybrids do indeed operate in that manner.
FULL hybrids don’t have any type of connection like that; instead, there is an indirect linkage via a PSD (Power Split Device).
FULL hybrid decleration begins as soon as the accelerator-pedal is released, before the brake-pedal is ever touched. The smaller of the two motors changes from generator to REgenerator, spinning independently of the engine’s crankshaft. Later when the brake-pedal is pushed, the REgenerating task is switched from the smaller motor to the bigger motor. Friction brakes will join in following that, if needed.
FULL hybrids are very, very different from ASSIST.
Jan 29th, 2008 (3:15 pm)>> FULL hybrid decleration begins as soon as the accelerator-pedal is released
I was really speaking about electric motors in general so I don’t know why you’re bringing this up.
But I will say that I consider it a design flaw if the car starts slowing down and regenerating energy without me touching the brake pedal.
I have experienced this behavior in the Prius and it is infuriating.
Jan 29th, 2008 (4:06 pm)Re: 28963 or self-labeled # 23 Noel
Are there 110,000 auto workers left in the US?
I’ll tell you gang, I love the idea of the US beating the rest of the world to the Volt/E-REV mass production concept, BUT…
The idea of having this vehicle produced across the globe and delivered to us with an US corporation’s (GM) name on it leaves a VERY bitter taste in my mouth. it’s great that our design engineers will have played a major role in the vehicle’s development but that is a very small number of jobs compared to the production line. Those of us that signed Lyle’s list are interested in the volt for one of a few reasons. Among them would be the environment, terminating our dependance on fossil fuels, the possibility of combining this vehicle with home photovoltaics in order to drive on sun power, WHATEVER! I think we should all also factor in the importance that this product could have on our nation’s economy. Remember, “It’s the economy stupid” (sorry, not you). Thousands of manufacturing jobs could be brought home to keep some of our nation’s remaining dollars here at home. We can’t survive as a consumer/service economy for much longer. We HAVE to PRODUCE SOMETHING to bring funds back into our economy!!! Employing thousands of US auto workers would go a long way toward revitalizing a number of hard hit areas in our country.
Government incentives, Tax breaks, union concessions, and a couple thousand extra dollars from the consumer would all be worth it. Lyle, is there a way to begin a “Build It Here” campaign on the site?
It’s been said that the GM big wigs check in on this site every now and then. If you (the reader) happen to be one consider this. There will be very few of us left who can afford vehicles like this if the economy collapses from our massive trade deficit. Picture the add campaign you could create waving that flag and flying that eagle if you can taut this vehicle as nearly all US made (have to be realistic with electronics and what not). Advertise that the car costs 32k instead of 29k because your employing US auto workers in an effort to save our country. Tell the potential buyers about the teamwork you will have created between GM, the UAW and the US govenment in order to make this happen. This type of campaign worked for Saturn when they came out, take it further. Subaru, toyota, etc are all telling us how they are employing US auto workers. Lets see you bring it home.
My bottom line is this. I’m waiting for the Volt for now but, when it comes to crunch time, I will factor in who is getting my dollars. If it comes down to a foreign nameplate assembled/built here vs a GM (or other US nameplate) shipped here by cargo freighter you will lose out. MY DOLLAR IS GOING BACK TO US WORKERS WHENEVER POSSIBLE! Corporations are so internationally entangled that I could care less who’s name is on the bumper.
All right… Enough preaching… Now, back to techs, specs, and dreams…
Jan 29th, 2008 (5:30 pm)Hermie, 4:06 PM:
Thank you very much.
Jan 31st, 2008 (5:14 am)Why are electric wheel motors so expensive ?
You could have x2 wheel or x4 wheel drive with no constant velocity joints.
May be the limitations are unsprung weight, plus the controller would be more complicated if you wanted to impliment stability control ! WOW !
I guess a single AC motor will do for now….
Cheers!