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Using a UPS to charge Li-Ion
#1
I've got a 3KW Braga Moro Memo Plus RTll off ebay and thinking about using it to charge a Li-ion 20s Pack

From the data sheet
 
DC side is 72 Vdc.  It doesn't specify the charge current. It was designed for Lead Acid Batteries 


Has Anyone got experience with UPS chargers ?  How much current do they usually provide to charge the battery and what charge mode they use ?

More pictures
 
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#2
Using UPS' to charge batteries is fine, albeit slowly. Also, the problem is they don't charge with the proper curve, so the batteries will never get fully charged, or they'll take a very long time to do so.
Also, as you brought out, the charging current isn't listed. Probably because it's not much. I would gather the current is close to 5A, maybe 10A at the most. If you read the owners manual for installation and setup, it probably says to let the unit charge for 24hrs or something like that before you put into operation. Most people just drop it in and plug everything up.

It's recommended to use a separate charger to handle the charging of the battery, a separate bms of some sort, and let the UPS be just an inverter and/or automatic transfer switch.
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#3
Agree with @Korishan. If you set your battery so it needs charging (and lower than UPS) you can use a clamp / amp-meter to measure charging current to see what you have.
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#4
Ok

In the meantime

Are there any CC/CV chargers for 72 Volt packs ?
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#5
I don't think I'd trust one of these too much, make sure you're using a good BMS, but there's tons of 72V/84V max chargers on eBay: https://www.ebay.com/itm/84V-1-4A-Lithiu...3726594543
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