I am new to this. I just purchased an all in one inverter/charge controller. The charge controller is 48V. To save quite a bit of money, I wanted to use four 12V batteries connected in series. Is it ok to have a 48V charge controller connected to four 12V batteries in series? I know that the bolts coming out of the batteries will be 48. I want to make sure that the same theory works for the power going into the battery system before I make a mistake. Many thanks!
Series of Four 12V Batterries To 48V Charge Controller?
- Thread starter sshaun302
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acdoctor
Solar Enthusiast
“12 V batteries “ is painting with a wide brush but yes that will get you going. There are many 12 volt batteries on the market. Some aren’t desirable at all.
RCinFLA
Solar Wizard
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Check the battery specs to see if and how many stacking is allowed. If specs say nothing about it then likely not stackable. Issue is internal BMS cutout switching MOSFET voltage rating. A BMS's for 48v system need 80v to 100v breakdown voltage rated MOSFET's.
BattleBorn states stackable to four 12 v batteries and they use 100v MOSFET's in their internal BMS.
BattleBorn states stackable to four 12 v batteries and they use 100v MOSFET's in their internal BMS.
Thanks for the responses. I am planning to use something like four 12v lithium batteries....maybe a Zooms Lifepo4 with 200AH. I thought it would work, but was afraid th 48 volts coming in from the charge controller and did not want to make a mistake. I will look at the battery specs before purchasing them. I attached the specs of the all in one system that I bought.
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RCinFLA
Solar Wizard
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You will have to check actual battery spec. Maximum of 51.2v doesn't make any sense for a 48v system as that would be 12.8v per battery or 3.2v per cell which is not enough to charge the battery. That would be nominal mid state of charge voltage. Max full charge would be 16x 3.65v = 58.4vdc.
On Amazon:
" Zooms 12V 200Ah LiFePO4 batteries can be connected in parallel or in series for larger capacity (Max.800Ah), and higher voltage(Max. 51.2V). The Max. energy is 40.96kWh, and Max. Load power is 20.48kWh, which is easy for you to operate the 12V lithium batteries at any time and anywhere. Zooms 200Ah battery is perfect for solar home system"
On Amazon:
" Zooms 12V 200Ah LiFePO4 batteries can be connected in parallel or in series for larger capacity (Max.800Ah), and higher voltage(Max. 51.2V). The Max. energy is 40.96kWh, and Max. Load power is 20.48kWh, which is easy for you to operate the 12V lithium batteries at any time and anywhere. Zooms 200Ah battery is perfect for solar home system"
acdoctor
Solar Enthusiast
If the internal cells of the 12 volt batteries are normal prismatic cells then their safe operating voltage is 2.5 min and 3.65 max. 4 cells per 12 volt battery, 4 batteries in series to make 48 volts. 2.5 volts x 16 cells = 40 volts
3.65 volts x 16 cells = 58.4 volts.
Nominal voltage is 3.2 volts per cell = 51.2 volts
I think that is where the Amazon info comes from.
3.65 volts x 16 cells = 58.4 volts.
Nominal voltage is 3.2 volts per cell = 51.2 volts
I think that is where the Amazon info comes from.
