it would seem so very simple to have simply given me the price when i asked for it that i am still amazed at how incompetent (can't think of a better description) the alibaba provided connection was...
but anyway with a minimum of fuss the Calib Power people quickly shot me back a $1.35/ah and the names of a couple of BMS producers that they feel alright about... i thought that perhaps they produced their own BMSs which would be a natural business opportunity for anyone who sells the cells....
so i believe that i am on the right track now... there are the cheap multiMULTI cell LiFePO4 packs that they sell for bicycles and such and these can go for less but are built in a completely inappropriate way... and there are assembled systems that go for almost twice what they should but this stuff from Calib looks very good.... probably going to end up at just a bit over 5k for the 48v, 200ah plus a good BMS... didn't understand how to get to these numbers but now that I am there the price tag Calib quotes suits me just fine.....
the combination of longer life (i'll probably go for 3000 cycles with lower DOD), deeper discharge capability in a pinch and lighter weight makes them hard to pass up.... over the long haul they are less expensive than lead acid and certainly give better overall performance...
not here but it was suggested that i run without a BMS..... that would seem to be an attempt to run my diesel with half the oil to save the weight???... it would probably work for quite awhile but when it finally doesn't work the penalty is catastrophic.... to me this is the place where lead acid and Lithium technologies really diverge.... one can get away with simple passive balances when using lead acid but not with the lithium stuff....
just rambling again..... thank you all those walked me through this.... we really ought to mention Calib every once in awhile so that anyone considering LiFePO4 tec will no where to go for some straight answers
From: Eric <ewdysar@yahoo.com>
To: electricboats@yahoogroups.com
Sent: Wednesday, April 18, 2012 1:44 AM
Subject: [Electric Boats] Re: trying to get prices from Alibaba contact (a rant)
Hi Michael,
Like I alluded to before, Alibaba is typically used for large wholesale purchases. I have a friend that is a purchasing agent for a very large corporation, he uses suppliers that show up on Alibaba. Because his company uses more textiles, India can often supply the best prices for orders that fill multiple shipping containers.
I once personally found an obscure extrusion available from an Alibaba vendor, the minimum order was 1000 linear feet, I needed about 3 feet. I changed my design to something more accessable....
You might have gotten a better response from your offshore vendor if you had been looking for 50 complete battery packs or so. Or maybe not.
The last that I did serious price analysis on LiFePO4 cells, the price of complete packs in the US including strapping and cell connectors was about $0.45/Wh. 16 passive BMS modules should cost less than $250. So if your target traction bank size is 10kWh (sixteen 200Ah cells), I would expect to pay less than $5000 with basic BMS capabilities. I know that there are some vendors that will gladly charge twice that for the same capacity. For estimating, I use $.50/Wh for LiFePO4 battery banks. You might find some pricing that looks a little bit better, but once you add in shipping and taxes (plus tariffs if coming from offshore) they all come in pretty close to that figure. An interesting thing is that this price is a little higher than what I found 2 years ago, I'm not sure exactly why but prices for these batteries has gone up around 10% in the interim. Now you know what a reasonable price is and if you find a better deal, you'll know that you've done good.
Fair winds,
Eric
Marina del Rey, CA
--- In electricboats@yahoogroups.com, Michael Mccomb <mccomb.michael@...> wrote:
>
> i am definitely going to be working with "local" suppliers assuming that turns out to be possible... i went the -Alibaba connection route because with a google search it popped up a unit that appeared to be exactly what i needed.....
>
> i guess my intent was simply to report what was happening to a newbie who ventured into the realms of "alibaba" for equipment.... at no time has having done so proven to be helpful
>
> kinda have to wonder what the point of alibaba is being as they seem to go so far our of their way NOT to sell through it....
>
>
Like I alluded to before, Alibaba is typically used for large wholesale purchases. I have a friend that is a purchasing agent for a very large corporation, he uses suppliers that show up on Alibaba. Because his company uses more textiles, India can often supply the best prices for orders that fill multiple shipping containers.
I once personally found an obscure extrusion available from an Alibaba vendor, the minimum order was 1000 linear feet, I needed about 3 feet. I changed my design to something more accessable....
You might have gotten a better response from your offshore vendor if you had been looking for 50 complete battery packs or so. Or maybe not.
The last that I did serious price analysis on LiFePO4 cells, the price of complete packs in the US including strapping and cell connectors was about $0.45/Wh. 16 passive BMS modules should cost less than $250. So if your target traction bank size is 10kWh (sixteen 200Ah cells), I would expect to pay less than $5000 with basic BMS capabilities. I know that there are some vendors that will gladly charge twice that for the same capacity. For estimating, I use $.50/Wh for LiFePO4 battery banks. You might find some pricing that looks a little bit better, but once you add in shipping and taxes (plus tariffs if coming from offshore) they all come in pretty close to that figure. An interesting thing is that this price is a little higher than what I found 2 years ago, I'm not sure exactly why but prices for these batteries has gone up around 10% in the interim. Now you know what a reasonable price is and if you find a better deal, you'll know that you've done good.
Fair winds,
Eric
Marina del Rey, CA
--- In electricboats@yahoogroups.com, Michael Mccomb <mccomb.michael@...> wrote:
>
> i am definitely going to be working with "local" suppliers assuming that turns out to be possible... i went the -Alibaba connection route because with a google search it popped up a unit that appeared to be exactly what i needed.....
>
> i guess my intent was simply to report what was happening to a newbie who ventured into the realms of "alibaba" for equipment.... at no time has having done so proven to be helpful
>
> kinda have to wonder what the point of alibaba is being as they seem to go so far our of their way NOT to sell through it....
>
>
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