Posted: Sat Apr 28, 2007 1:28 am Post subject: Re: Electric cars viable since late 1990s. Politics the prob
The Ovonics were suitable for any normal driving in virtually all climates. EV1s did have packs which would overheat while being flogged around in the deserts of California and Arizona with heavy accelerations and repeated bursts to 80 mph, and then promptly recharged, but otherwise, the problem was minimal. You'd really have to be abusing the hell out of the car in 110 degree weather and recharging it often to get it to overheat from what I've heard.
These are the same Ovonics that Aerovironment could repeatedly charge from 0-80% in 20 minutes with no noticable impact on life and no noticable problems.
Panasonic's batteries mostly corrected the overheating problem with reduced internal impedance. Never heard of any RAV4 pack overheating.
Please understand that I do not speak from experience on this issue as I've never driven an EV1 or RAV4 EV.
NiMH tend to do better in cold climates than warm. In extreme heat, the BMS for an EV pack might be set to allow less current draw or less charge current so as to prevent overheating if the temp got high. _________________ The unnecessary felling of a tree, perhaps the old growth of centuries, seems to me a crime little short of murder. ~Thomas Jefferson
Posted: Sat Apr 28, 2007 10:19 am Post subject: Re: Electric cars viable since late 1990s. Politics the prob
The_Toecutter wrote:
The Ovonics were suitable for any normal driving in virtually all climates. EV1s did have packs which would overheat while being flogged around in the deserts of California and Arizona with heavy accelerations and repeated bursts to 80 mph, and then promptly recharged, but otherwise, the problem was minimal. You'd really have to be abusing the hell out of the car in 110 degree weather and recharging it often to get it to overheat from what I've heard.
These are the same Ovonics that Aerovironment could repeatedly charge from 0-80% in 20 minutes with no noticable impact on life and no noticable problems.
But didn't the EV1s you mention have active cooling for the batteries during charging and driving, or was it only during charging? (I've read conflicting reports.) Same for the NiMH batteries in the Ford Ranger EV and S-10 EV, as mentioned in these links?
NiMH battery versions of the '99 cars will be produced at the end of 1998. It was confirmed that battery cooling was a major issue, and that this technical problem was solved by using the air-conditioner to force cool air into the battery tunnel.
My interest stems from the possibility of using Ovonics in my own project, but if they require active cooling that makes it less feasible. _________________ The shovel with a wheel - The Wovel.
http://wovel.com/
Posted: Fri May 18, 2007 3:01 am Post subject: Re: Electric cars viable since late 1990s. Politics the prob
Quote:
But didn't the EV1s you mention have active cooling for the batteries during charging and driving, or was it only during charging? (I've read conflicting reports.) Same for the NiMH batteries in the Ford Ranger EV and S-10 EV, as mentioned in these links?
I believe the active cooling was only during charging. I may be wrong though.
Quote:
My interest stems from the possibility of using Ovonics in my own project, but if they require active cooling that makes it less feasible.
I would highly recommend active cooling for them if you intend to use them for a vehicle capable of highway speeds. It would be nice to have access to the Panasonic EV95, as they greatly mitigated the overheating problem. Oh well. At least EV bones has a few used large format Ovonic modules, at like $500 a piece.
I may eventually use a set in my GT6, but I wouldn't go about it unless I had an absolutely foolproof way to prevent them from overheating. But consider that this car is being built for high power and high performance. Most vehicles equipped with Ovonics should fare ok without any active cooling(during charge or discharge) if they are driven modestly and charged slowly. _________________ The unnecessary felling of a tree, perhaps the old growth of centuries, seems to me a crime little short of murder. ~Thomas Jefferson
Joined: Nov 01, 2005 Posts: 796 Location: Euro high horse bastard on the run
Posted: Fri May 18, 2007 3:27 am Post subject: Re: Electric cars viable since late 1990s. Politics the prob
Hi Toe, we are probably both leaning more towards the efficiency side of things for EVs. But just for the performance freaks the following kitcar could be a great glider for this application. Using the bigger Zilla controller which could supply upto 800HP peak this would be a blast. Incl. high voltage pack of high discharge pulse capable batteries like Hawker/Oddyssey or some li-polymers if budget is not a problem.. So Tesla Roadster killer for sub $50k is perfectly feasible..
Note, FFR kits are the leaders of the racing kitcar industry in the US and in the int. comparison as well. According to their forum, someone in northern CA is supposedly building the first electric one..
Posted: Fri May 18, 2007 3:51 am Post subject: Re: Electric cars viable since late 1990s. Politics the prob
I once considered building an electric GTM Libra, until I realized that the price was too far out of my range.
That car you posted is just plain sexy. I'd love twin ACP drivetrains, a 1,400 pound pack of Kokam Li Poly, and a 3-speed transmission with the 3rd speed optimized to allow 200+ mph top speed in a body like that. Think about it, < 200 Wh/mile at 60 mph is possible with a car of that sort, yet you'd be able to have blistering performance when you want it. _________________ The unnecessary felling of a tree, perhaps the old growth of centuries, seems to me a crime little short of murder. ~Thomas Jefferson
Joined: Nov 01, 2005 Posts: 796 Location: Euro high horse bastard on the run
Posted: Fri May 18, 2007 4:28 am Post subject: Re: Electric cars viable since late 1990s. Politics the prob
Very nice, but your dream setup with double ACPs and Kokams is above 100k.
I was more thinking about the more affordable "white zombie" approach - 2000A DC Zilla, 300V system, Oddyssey lead acids 16-26Ah cells capable of 750A from their 6kg of weight etc..
Another setup, like ProEV "electric Imp" double Siemens Simoverts (2x100kW AC inverters a bit less at the motors).. Simovert combos with ~50kW motors could be sometimes found at discount for cca $4-5k each. So, then it depends only on the batteries (range demands) if you can make it bellow say $60k..
Btw. did you try to contact Electrolux/Husqvarna about the Firefly batteries (for their garden equipment) in your area? They are due Q4 2007- Q1 2008. So far from my limited experience they were pretty much annoyed that there is an interest just for the Firefly batteries. The Firefly co. presumably wants to delay its OEM automotive production and cash out on big deals with Detroit and the army, which is kind of silly, because the guys from Detroit are not comming and the asians seem to place bets heavily on lithium instead. In my view, the best approach would be to get the next gen lead acid technology on the market as soon as possible be it hobby market first etc.. _________________ DOOMerotron: at all-time high [8.1] out of 10..
Posted: Fri May 18, 2007 4:56 am Post subject: Re: Electric cars viable since late 1990s. Politics the prob
A 200+ mph supercar for $100k would really be quite a bargain considering the asking price for such cars is usually $200k or more!
I badly want access to 80+ AH Firefly batteries. Another affordable ticket to 200+ miles highway range, if only they'd be willing to sell. _________________ The unnecessary felling of a tree, perhaps the old growth of centuries, seems to me a crime little short of murder. ~Thomas Jefferson
Joined: Nov 01, 2005 Posts: 796 Location: Euro high horse bastard on the run
Posted: Fri May 18, 2007 5:41 am Post subject: Re: Electric cars viable since late 1990s. Politics the prob
Unfortunately, I doubt the first production run of Fireflys will be as high as 80Ah cells, they are targeting powertools-smaller lawnmowers and garden tractors. So given the higher discharge properties in comparison to AGMs - one can reasonably assume it won't be above 50Ah..
There are some older news reports and pictures as they test those Electrolux/Husqvarna garden tractors in their lab, and if I recollect it correctly, they were ~55Ah..
But even mid range voltage AC systems in efficient glider can make use of these 12V@55Ah, think AzureDynamics/Solectria inverters can start from cca 144V battery nominal voltage pack, right? There are few other similar AC system companies..
78kW @ 312V (peak) - 38kW @ 312V (cont.) => this would be a blast in ultralights such as Loremo or some 450kg Lotus7 style kitcars..
http://www.electroauto.com/catalog/accontrol.shtml _________________ DOOMerotron: at all-time high [8.1] out of 10..
Last edited by Mesuge on Fri May 18, 2007 5:51 am; edited 1 time in total
Posted: Fri May 18, 2007 5:50 am Post subject: Re: Electric cars viable since late 1990s. Politics the prob
Hell, even 50 AH Fireflys would be more than welcome by me! A 348V, 50 AH pack with Zilla 1k would offer 17,400 WH on board. It would be ~600 pounds lighter than an 1,125 pound Optima pack, so 110 Wh/mile at 65 mph would be in grasp for the electric Triumph GT6.
That's 160 miles range!
I'd be willing to settle for a meagre 120 battery horsepower if I could get that range. With a Zilla 1k and Netgain WarP 9" motor, that would still be 0-60 mph < 8 seconds in a 1,900 pound car. To see range jump from a projected 100 miles to 160 miles would be a huge improvement, nevermind the low operating cost.
Anything smaller than 50 AH though, and I'll use conventional AGMs until I can afford better. Conventional AGMs is 0-60 mph in < 6 seconds tire roasting fun, in a fat, overweight 2,500 pound sports car, and about 100 miles range at 65 mph. _________________ The unnecessary felling of a tree, perhaps the old growth of centuries, seems to me a crime little short of murder. ~Thomas Jefferson
Joined: Nov 01, 2005 Posts: 796 Location: Euro high horse bastard on the run
Posted: Fri May 18, 2007 6:11 am Post subject: Re: Electric cars viable since late 1990s. Politics the prob
Well, as they say it's always a compromise..
Nowadays you can have lithium-ion/polymer from TS or Kokam for $.35/Wh volume or ~$.5/Wh in retail pricing. Now -ion can supply only 3C continuous and 5C max. pulse discharge currents without too much affecting the cycle life, -polymer should handle 2x more. And 1500 cycles to 70-80% DoD as opposed to 450 cycles with quality AGMs like Hawker-Genesis-Oddyssey/Exide Orbitals.
So, if you add BMS and run the operational costs per km/mi I think it's apparent that the AGM/gel are out of loop in the area of efficient - not sporty EV applications already.
And in the area of high performance EV - it's still a bit better for AGMs but at the cost of range, not every glider/platform can haul two ~300V packs in parallel, it's just too heavy even with small 16-26Ah (6-11kg-> 400-700kg) cells..
What I'm most worried about in Li-ion/polymer is the shelf life! I suspect it's even 2x less than from NiMH Ovonics, so sub 5-7yrs performance. The situation in Li-nanophosfate like A123/Altairnano should be in this respect a little bit better, but still these are and will remain too expensive in the mid-term.. _________________ DOOMerotron: at all-time high [8.1] out of 10..
Joined: Nov 01, 2005 Posts: 796 Location: Euro high horse bastard on the run
Posted: Fri May 18, 2007 9:17 am Post subject: Re: Electric cars viable since late 1990s. Politics the prob
Firefly> worth reading those new PR articles on their website, haven't been there for a while. No confirmation about the q4/q1 2007-8 for Electrolux/Husqvarna (which is a bad sign) but new announcement about q4/2007 of battery production for the army, hah wanna enlist? Also they mentioned some mauf. agreement with the Crown batt. co.
Also, on more occasions they were presenting with that much sized type of the plate not sure whether it is their "3D" or "3D2" technology but definately looks as a sub 55Ah model. In one article they compare internal resistance with spiral lead acids - AGMs and discharging it 5C in the end with just slight increase unlike the AGM.
Another feature, only 40% capacity loss at -20C so that's sounds all jollygood and promising..
At least from their website they plan to start in automotive with the more powerfull "3D2" - so this will be delayed for several years. Lets hope those basic "3D" will be on the shelf for us mortals and in practice much an improvemt over gel/agm anyway.. _________________ DOOMerotron: at all-time high [8.1] out of 10..
Posted: Sun May 20, 2007 2:34 pm Post subject: Re: Electric cars viable since late 1990s. Politics the prob
I can't wait to have the money to experiment with all these new technologies. I suspect the Firefly batteries could operate just fine if paralleled. _________________ The unnecessary felling of a tree, perhaps the old growth of centuries, seems to me a crime little short of murder. ~Thomas Jefferson
Posted: Sat May 24, 2008 3:14 pm Post subject: Re: Electric cars viable since late 1990s. Politics the prob
Gas is nearing $4/gallon in the U.S., and OPEC has mentioned the possibility of $7/gallon in the U.S. and $200/barrel this Fall. Who here is pissed that this alternative has been denied to us?
These things work dammit.
If you haven't done so, IO sugest you build one. If you cannot afford to convert a car, an electric bicycle will still be better than walking, and can be done for under $1,000 for something that hits 40+ mph. _________________ The unnecessary felling of a tree, perhaps the old growth of centuries, seems to me a crime little short of murder. ~Thomas Jefferson
Posted: Sat May 24, 2008 6:11 pm Post subject: Re: Electric cars viable since late 1990s. Politics the prob
I have to say I'm somewhat underwhelmed with the first iteration
of the Firefly 3D technology in their Oasis battery.
Comparing it to the Odyssey group 31, which you can actually buy right now, it doesn't look that much better.
Odyssey PC 2150:
75 lbs.
CCA: 1,090A at 0°F
Reserve capacity: 200 minutes on 25amps
Deep cycling capability: 400 at 80% DOD
Design life: 12 years
Typical service life: 6 to 8 years
Odyssey PC2150
Oasis:
70 lbs.
CCA: 650
Reserve Capacity: 215 min @25A
Deep cycling capability: 800 at 80% DOD
Firefly PDF
So the Oasis may last twice as long as the Odyssey, which is impressive, but seems to have half the CCA, and everything else is about equal. It will be interesting to see how they price the Oasis. _________________ The shovel with a wheel - The Wovel.
http://wovel.com/
Posted: Sat May 24, 2008 10:24 pm Post subject: Re: Electric cars viable since late 1990s. Politics the prob
Those look appealing IMO! Only ten pounds more than a t-105 but nearly three times the energy output, and deeper cycling actually increases the amount of available energy! As long as those aren't more than ~$400/battery they are definitely cheaper in terms of energy output. _________________
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