Golden_HVAC wrote:
I recently learned that a Lithium battery can accept power at greater than 100 amps. So the RV in question had a limiting device on it to restrict the amperage going into the Lithium battery pack, so not to melt the alternator. In your case, you might have a 20 amp circuit breaker feeding the camper +12 circuit, and that fuse would quickly trip if the truck is 14 volts and the battery 12.5. A auto reset circuit breaker might help, or run a second power line that is sized at 30 amps and a auto reset circuit breaker that size?
it doesn't matter what it can accept, it is not going to force a 30 amp controller or a 40 amp controler to put out more power than they are designed to. The alternator one is a wife's tail, and the video was rigged to be able to do it as a sales gimmick. in reality you will never get enough power through the small charging wires to ever hurt the alternator. The limiting device was most likely a DC to DC charger which will throttle the output from the alternator like you have said but will also provide the proper charge profile to the LiFePO4 battery while you are traveling. this is handy as you can limit how fast it will be able to charge to keep the load low on your alternator while still running larger charge cables to have a lower voltage drop.
the real thing is that they can accept more charge and they will charge more efficiently than a lead acid battery, so if you limit the charge to 30 amps to make sure the load on your alternator is below 50% when everything is running, the LiFePO4 battery will reach a full charge faster. as for 500 watts of panels that's about what I am shooting at especial if you use 120v stuff. The price of panels is dirt cheap, and I set up my systems to be able to recover from the previous night's usage by noon on a nice day. Right now, I have 325watts and I am adding a second one when I add the inverter.
by oversizing a bit, it just makes it, so my batteries stay at 100% from noonish until it gets dark as the panels supply the daytime usage even if I am running the furnace and stuff. but what it is really good at is if I get a few days of bad weather and no charging then when the sun does come out the capability is there to get me back to 100% in one day.
