I live full time on a boat. For a solar system this means shading problems because of all the rigging. I wire my panels in parallel because of this. On cloudy days or days when we put a heavy load on, like running computers or run the watermaker we need to fire up the engine and charge the batteries. I have a 70a alternator controlled by a 3 phase charge controller. Right now my battery bank is two T105 Trojans 225a. But they are failing after 3 years. The reason I want to switch to Lifepo4.
I know there are problems that need addressing to do this safely.
1) when the BMS sees that the battery is full it shuts off the charge current. This would fry an alternator. I have a solenoid that connects my house batteries and my engine start battery When it senses a charging current. So when the Lifepo4 shuts down charging the circuit would still be connected to my start battery. Granted only trickle charging at that point but enough to save the alternator. Any problems with this theory?
or I could purchase a Sterling alternator protection device if my scenario is a little dicey.
2) I understand that a Lifepo4 can suck up everything an alternator can put out. This can overheat an alternator to the point of failing. My three phase charge controller has an alternator Tempture probe that will shut off the alternator if it gets too hot. Anybody have one of these? Does it work as advertised? How else can I safeguard the alternator from overheating while charging a Lifepo4? I could get a DC to DC 50a battery charger to feed the Lifepo4.
I have 3x100w solar, wired in parallel. Going through a 20 amp MPPT controller charging a Trojan T105 flooded battery bank (225a). I will be replacing the 105’s with a 150a Lifepo4.
All input considered.
I know there are problems that need addressing to do this safely.
1) when the BMS sees that the battery is full it shuts off the charge current. This would fry an alternator. I have a solenoid that connects my house batteries and my engine start battery When it senses a charging current. So when the Lifepo4 shuts down charging the circuit would still be connected to my start battery. Granted only trickle charging at that point but enough to save the alternator. Any problems with this theory?
or I could purchase a Sterling alternator protection device if my scenario is a little dicey.
2) I understand that a Lifepo4 can suck up everything an alternator can put out. This can overheat an alternator to the point of failing. My three phase charge controller has an alternator Tempture probe that will shut off the alternator if it gets too hot. Anybody have one of these? Does it work as advertised? How else can I safeguard the alternator from overheating while charging a Lifepo4? I could get a DC to DC 50a battery charger to feed the Lifepo4.
I have 3x100w solar, wired in parallel. Going through a 20 amp MPPT controller charging a Trojan T105 flooded battery bank (225a). I will be replacing the 105’s with a 150a Lifepo4.
All input considered.
