No arguments here…definitely was a conspiracy and capitalism at its finest that led to patent ownership that kept companies from producing large size NiMH batteries for EV use. Thank you Ovonics and Chevron! And in my opinion they shot us all in the foot---the head start they had in this was squandered by their keeping this technology from the market and allowed investments in lithium cell technology to jump ahead leaps and bounds. Few folks rave about NiMH batteries anymore, particularly since the cost of lithium keeps dropping and more and more manufacturers are switching to the easier to make lithiums instead of the NiMH batteries.
I had a set of NiMH batteries from an EV1----some of the cells were too dead to be revived.
I gave them to another fellow EVer here in Portland as I couldn’t trust them and didn’t want to get into mixing/matching cells and having to reband them to the right tension. My experience with those and smaller scale NiMH batteries led me to not be a big fan of NiMH.
I’m not a big fan of lithium either though.
Waiting to be convinced by quality and pricing.
-Myles
From: electricboats@yahoogroups.com [mailto:electricboats@yahoogroups.com] On Behalf Of Don Parsons
Sent: Sunday, November 14, 2010 1:16 PM
To: electricboats@yahoogroups.com
Subject: Re: [Electric Boats] Picking batteries
Myles,I agree partially,
The exception being for a home powerbank they are the answer even with their high cost and lower performance. In the long run you will save.
What pisses me off is we are being cheated out of their potential.
Not even future potential, but 1970's potential!
That 70's patent is way past expiration but is being held from us. Why.
Our military supposedly is sitting on 40 year old technology. The notion is absurd.
The Be Utility Free Chinese made NiFe is old technology compared
to the Eagle-Picher technology and that is now 40 years old.
Where could NiFe be now if Excide hadn't shelved it.
Sadly we may never know.
If any of you can get your hands on the T-van batteries then I think they would be worth a try in a boat.
I believe there was a post in 2009 by a member who said he had some dead T-van batteries he was going to try to revive. If you read this let us know if they worked.
Hope I didn't rant too much.
Don Parsons
--- In electricboats@yahoogroups.com, "Myles Twete" <matwete@...> wrote:
>
> >A Peukert exponent of 1.00 means that there is no Peukerts effect at all
> and that the battery will deliver the same amount of energy at any discharge
> rate. I would guess that the Peukert's exponent for Nickel Iron batteries is
> higher than 1.00
> >Eric
>
>
>
> No doubt. References online claim virtually no Peukert effect for any of
> the Nickel chemistries including NiCd, NiZn, NiMH.
>
> I'm sure he just was parroting these. Worse, the weblink he offered drawing
> folks to his personal Peukert calculator page does not provide any support
> for the 1.0 Peukert exponent claim.
>
>
>
> From the brief looking I've done, I'd guess that the effective Peukert
> exponent for NiFe is below 1.05, and once you're down that low, unless
> you're drawing high-C loads, I don't think you have to worry much about it.
>
>
>
> I think the major beefs against NiFe batteries are:
>
> . Cost
>
> . Relatively high self-discharge rates
>
>
>
> And those weigh enough against them that we don't appreciate the uber-long
> life of them. Charge/discharge inefficiency isn't much of an issue for many
> of us, but high initial cost and self-discharge rates are.
>
>
>
> -Myles Twete
>
No comments:
Post a Comment