GM Volt Forum banner

1 - 9 of 9 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter #1
Lyle, I enjoyed your podcast interviews with A123 and CPI. It's great that you can get that access but there is one question I wish you had asked and that is "what energy density are they targeting for their batteries"? They might not have divulged that information but in my opinion it is the key.

The EESTor energy storage device being developed for ZENN promises 52 KWh in a 336 lb package or an energy density of 0.34 KWH per Kg. I would be very interested in what A123 and LG Chem are shooting for. GM specifications say that the energy in their battery will be a minimum of 16 KWhrs but they don't say what it will weigh. Do you have any information on this? Does GM have a target KWH per kg energy density?
 

·
Registered
Joined
·
1,916 Posts
For BEV only cars and in the long run energy density it will be extremely important, but for limited AER EREV's like the Volt cost is cost and volume energy density are more important. The 1st generation Volt will be limited to 4 seats because of the volume the battery occupies and until price comes down the majority of users will only want AER range that will be utilized regularly.
 

·
Registered
Joined
·
6 Posts
Discussion Starter #3
OK, Koz. Volume density would be useful to know as well. The EESTor claim is for 52 KWHrs in a volume of 1.2 cu ft. I don't know what volume density GM is targeting or what A123 or LG Chem are going to deliver. Do you?
 

·
Registered
Joined
·
495 Posts
Whatever A123 is working on probably won't beat the specs of the EEStor EESU. Here's EESU compared to (non-nanoscale electrode) Li-ion batteries.

Energy Density
EESU: 0.28kWh/kg
Li-ion: 0.20kWh/kg

Production Cost:
EESU: $62/kWh
Li-ion: $300/kWh

Self-Discharge Rate per Month
EESU: 0.01%
Li-ion: 5%

I want to see how well this technology holds up in ZENN cars (as I understand, they are just starting to use them, and planning on releasing a highway capable EV next year). After they prove it as a viable solution, I expect GM to immediately begin R&D of their own and make the switch. Li-ion will never reach $62/kWh. It's a waste even trying.
 

·
Registered
Joined
·
256 Posts
Keep in mind you can only use half of the available energy in the Volt. This effectively doubles the energy density of the EEStore Ultracap when comparing figures.
 

·
Registered
Joined
·
45 Posts
Did I miss something? Last I knew, EEStore products were not available, not verified, and still basically just a rumor, right?



Was there a press release I missed? Where do these figures (especially cost) come from?
 

·
Registered
Joined
·
13 Posts
EEStor only hype?

EEStor is still all hype with nothing to verify they have anything more than a windup toy at this point.
Please compare this to Bob Lutz' comment:

"Now, don’t run to the Chevy dealer and order your Volt yet: The “test mule” I drove - a previous-generation Malibu - wasn’t calibrated properly, and there are an awful lot of tests that this battery must pass before it’s cleared for production."
(from: http://fastlane.gmblogs.com/archives/2008/06/at_last_behind.html)

It doesn't sound like GM has nailed down a battery yet. Just because EEStor is in a quiet period, I don't think Zenn and Lockheed-Martin are wasting their time and money on vaporware. GM must be scratching it's head on this technology.
 

·
Registered
Joined
·
256 Posts
Don't misunderstand I am looking forward to seeing EEStor meet there press releases more than anyone! If true this would change the world more than anything I can think of ever invented.
 
1 - 9 of 9 Posts
Top