LiFePO4

[droid_ca]

I'm thinking about getting some LiFePO4 batteries and would like to use a solar panel with it. Does anyone know anything about this as I've found lots of conflicting information about it

[Shadow Catcher]

Unless you have a good source they will not give you much bang for a whole lot of bucks. On top of this they appear to not have great life cycles approximately 500 for one source.
The question probably should be what do you want to use the batteries for?
The place to ask the question might be http://www.wind-sun.com/ForumVB/index.php

[droid_ca]

thanks shadow catcher for that link I searched and found one 3 page article on it and to sum it up by switching to the new lifepo batteries there was a savings of.....
LiFePo, 54 usable AH, equals $4.77 / AHAGM, 37.5 usable AH, equals $4.61 / AH
And the weight!!:LiFePo, 5.51 lbs x (4) cells = 22.4 lbsAGM, 52 lbs
And the size!!:LiFePo: 8.5" x 2.4" x 4.5" or a bank of approx 8.5" x 10" x 4.5", or 383 cu in.AGM: 10.2" x 6.6" x 8.3" or 559 cu in.
That is all awesome until you confront the BMS. Do you really need a $200+ Battery Mgmt. System?

[Shadow Catcher]

It might be worth talking with the folks at Progressive Dynamics, if this becomes economically viable they might be able to program one of their units to work. Or you might find that it already works. If you have a link to a 12Volt ish battery pack that is not mega dollars I would love to see what is available.

[droid_ca]

alot of the stuff I've been finding has been used for the electric bikes and some of them are super crazy for the amount of ppwer that they hold you might need a dc to dc converter but that wouldnt be that bad

[wannabefree]

Li batteries require special care when charging. You cannot use a car battery charger. You'll spend $500+ on the battery, $200 on a decent charger and have an excellent battery that weighs a fraction of the lead the rest of us haul around. Whether the life/cost trade is worth it is an open question. I looked into them a couple years ago and couldn't justify the cost. The price hasn't really dropped much since then. Again, don't use a charger meant for lead acid. You'll turn your pricey batteries into bricks in no time.

[droid_ca]

there is a good deal on them now on another forum where there is a massive group buy and it'll be somewhere near 200 a kilowatt and I have charger already but thanks for the heads up