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Old 09-06-08, 06:29 PM   #1
misslexi
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LiFePO4 battery charger question

I just bought a 36v 20ah pack off eBay. Includes pack and BMS, no charger. Do I need any sort of special charger for this or does BMS take care of making sure the pack is fed right?

I found a nice SLA charger here: http://www.batterystuff.com/battery-...C0891-102.html

Is this overkill?
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Old 09-06-08, 06:45 PM   #2
wernmax
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Good question. If the BMS are designed for charging, then yes, they would terminate charge correctly. I use 12V 10ah packs, no BMS, but special 12v chargers just for that specific type of battery. Sans instruction, I don't know how you would know.

Ps, check each cells' voltage to make sure they aren't under 2.45v before charging. Those type batteries can be permanently ruined by falling too low, even once. If they're too low, they may not take a charge, and will heat up instead, eventually blowing the end out. At least, that's what a couple of mine did.
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Old 09-06-08, 08:37 PM   #3
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Thanks for the tip...looking at the eBay batteries, like ping for example, that come with 2-3 amp chargers for "free", I 'm thinking these are not very sophisticated units. Then again a BMS could be one that only monitors the discharge side and not the charge side, or vice versa. I'm hoping for both.

A number of threads I've read indicate a good SLA charger should work fine for the LiFePO4 with integrated BMS.

Brave new world out here, you takes your chances.
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Old 09-07-08, 08:53 AM   #4
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For more technical questions, try endless sphere.
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