So I would like to make a simple portable array with two 50 watt panels to use to charge a 12 volt 100ah battery. If the batteries are battleborn lithium and I keep the currant low can I go straight from the panels to to batteries or should a charge controller still be used? Maybe a smaller charge controller.
Portable backup Solar battery charger voltage question
- Thread starter Jgoodman
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Ampster
Renewable Energy Hobbyist
You will need a charge controller to make sure your battery gets charged to the correct voltage.
Basically so it doesn’t overcharge the battery, yes
chrisski
Solar Boondocker
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So the excess voltage does not fry the batteries or trip the BMS.
Not sure what happens when you over voltage a Lithium Cell, but when you put too much voltage in a Lead Acid Cell, the acids whether AGM, GEl, or FLA start to bubble. FOr FLA going a little high is the equalization (maintenance phase), and when I did this it the bubbling was so much it sounded like a stream.
Ampster
Renewable Energy Hobbyist
Over voltage and too much time at high voltage can reduce the life of Lithium cells.
So if the batteries get to low the bms trips and won’t run, and if the batteries bms trips then my scc goes off too. So how do I use a system like two panels and a charge controller to bring the charge back up on a battery where the bms has tripped?
chrisski
Solar Boondocker
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Set right the charge controller will start charging before the BMS kicks in. THe BMS is for In Case of Emergency (ICE).
Set the charge to the Battlborn spec sheet, absorption and float.
If the BMS needs to be rest because of low voltage, look in the BB manual. THe reset may be automatic after charged enough. My experience right now is with a cheap BMS with no readings, and if that has tripped, I will unplug the panels and it resets the BMS. No instructions in my manual.
I have started using a better Overkill BMS, and that appears that the low voltage discharge resets automatically by shuts off at a per cell voltage I set it to and waits to recover to a higher voltage I set, and regardless has a set amount it waits.
Not sure what Battleborn does.
Set the charge to the Battlborn spec sheet, absorption and float.
If the BMS needs to be rest because of low voltage, look in the BB manual. THe reset may be automatic after charged enough. My experience right now is with a cheap BMS with no readings, and if that has tripped, I will unplug the panels and it resets the BMS. No instructions in my manual.
I have started using a better Overkill BMS, and that appears that the low voltage discharge resets automatically by shuts off at a per cell voltage I set it to and waits to recover to a higher voltage I set, and regardless has a set amount it waits.
Not sure what Battleborn does.
