Charging DIY solar generator from a battery bank.

[dudeatlarge]

I have a diy 100 amp 12v solar generator with a 100 amp bms. I also have 800 amp 12v battery bank in the bed of my pickup. It is comprised of 4 200 amp batteries with 200 amp bms. I want to charge my 100 amp unit from the battery bank. Can I just plug them together with appropriate size cable to charge my diy 100 amp unit?

Tia, Doug

 

[Rednecktek]

The big battery is going to try to charge the small bank in a real hurry which is likely to to spark big and could trip the BMS.

 

[rodrick]

Highly recommend a dc to dc charger, if connected directly when there’s a big voltage difference it could end badly it’s just like connecting batteries in parallel you charge to same voltage then connect

 

[Vigo]

Im seeing 20a dc-dc charger for $56 and 40a for $71 (after applying coupons) with same day shipping on Amazon:

$56 20a

 

[dudeatlarge]

Thanks for the replies and recommendations. I didn't figure that it work out to well . I will get a small dc to dc charger to run into the cab of my truck to charge the 100 amp battery box.

Thanks again, Doug