Hi guys. I have an mppt controller 75/15 model HQ1746JV. My question is can this charger charge a 120 AH lithium or do i have to get a special " lithium" charger, and if so, what size should get.
asked
MPPT Controller
Hi @bricki 4 the short answer is yes (provided the battery has either an internal or external BMS) and you have selected the LiFePo4 charging profile (battery settings / battery preset).
The longer answer depends on the number and configuration of your solar panels, the expected overnight discharge of the battery, and the daily load. The 75/15 can take a maximum of 75 volts on the input with a maximum output of 15 amps.
Assuming the battery is 12 volts, there are sufficient solar panels, and you are in a relatively sunny location, it will take at least six hours to recharge the battery from a state of 70% discharge and that is assuming that there is no additional load. Additional loads during the day will slow down the charging process. Lower levels of discharge will speed up the charging process. So the long answer to your questions is 'it depends'. I hope that helps.
