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Is it a problem if I cant provide the recommended charging amps right away?

MorganCarey

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Jul 19, 2020
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Im trying to figure out if we are making the jump to LiFePO4 right now. We need to replace two of these: https://usbattery.ca/product/us-agm-250/
They have served us for 7 years of light duty but they are done. Basically this is a 12V 260ah bank. If I went out and replaced these today I'm looking at just south of $800 Canadian. I'm not sure I have the stomach for laying down that kind of cash right now on AGM batteries.

Now I'm looking at making a 12V 100ah LiFePO4 battery. All the batteries I'm looking at to build a 100AH bank will claim to have a standard charge rate of around 50 Amps. For example: https://www.electriccarpartscompany.com/Fortune-100Ah-Aluminum-Encased-Battery

I currently only have 260 Watts of 12V Panels which will give me a theoretical max of 21.6 amps. My hope is that if I can go with LiFePO4 now, with my current array, I can then add more panels at a later date to max out a new 40 or even 60 amp controller that I would also have to buy now. (currently on a MorningStar PWM 15 which doesn't support Lithium)

So, as per the thread title.....

If I can ONLY give the new batteries 21.6amps (max theoretical) now due to budgetary reasons, is this going to damage the new batteries?
 
Standard charge rate is just a reference, your batteries will actually be marginally happier at a lower C-rate. 0.2C to 0.3C (20-30A for a 100Ah battery) is pretty standard, and there is nothing wrong with going lower than that.
 
Charge rate really only matters with FLA/AGM. They really need to be charged around 0.1C or per the manuf's recommendations. Bad stuff happens, particularly at LOW current.
 
My 48v 60ah battery only charges at .17 C as that is the best I can do for now.

It may never charge above that rate and I don’t see it as a problem.
 
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