Hi Guys, In regard to LiFePO4 batteries in RV's I can provide the following advice.
I installed a "Vision" 100 amp Hr LiFePO4 mono cell in our caravan 4 years ago along with a Victron 75/15 Regulator, 2 x 195 watt panels, a Victron Smart Charger, and a Latronics 1500 watt inverter.
Dragged the whole lot around Oz for about 22,000 Klm's (just the West side), over many miles of really bad corrugations, no issues.
Problem was the battery output maxed out at 50 amps, so wouldn't run the microwave or coffee pod machine.
I have just upgraded to 4 x 200 amp aluminium case prismatic cells from Shenzhen RJ Energy Co. Ltd, a Daly 3 port 200 amp BMS.
I have put the 4 cells in a rotor molded plastic box I had, together with most of the foam the batteries came pack in (see pics), there is also foam under the cells, and under the box. This fits perfectly beside the inner wheel arch and the seat frame, and is held in place by 2 pieces of timber screwed to the floor either side. The inverter is under one of the two single beds, with a rotation polycarbonate cover for easy access to the switch.
Unfortunately the BMS I received was DOA, and has been sent back. The batteries are actually marked 210 amp hours, and seem to be very good.
I also bought one of the ISDT BG-8S balancers which Will reviewed which works a treat ( but slow on big batteries).
As I have stated elsewhere, (and mentioned by Will yesterday) with all the buggering around trying to work out what was wrong with the BMS, and testing for Daly tech's must have undone and re tightened the two main terminals about 30 times! End result was a stripped thread on the total negative, I repaired it with a helicoil, and today I did the main positive as well (much better job). unfortunately you can't remove the tang from a blind hole, but it is a far stronger than original (see pics) Those 6 mm. )by about 10mm. deep) terminals are ridiculously small.
Yesterday I ordered 10 of these studs to replace all the bolts currently fitted:
https://tinyurl.com/qsbqbgo
Because the ISDT BG-8S balancer has a programmable low voltage alarm, and I might have to wait 3 or 4 weeks to receive the replacement BMS, I decided to test the batteries without the BMS, keeping a close eye on the individual cell voltages via the ISDT BG-8S balancer (not in balance mode, just voltage).
After installing the battery with home made bus bars and fusing etc. I ran the microwave for 3 minutes at full whack, (about 1100 watts), no discernible battery drop, then made two cups of coffee (Aldi machine) draws about 1500 watts (inverter max). no discernible battery drop.
As I recently also bought a two burner (Aldi) induction cook top, I decided to give that a run. I ran it outside the van on an extension lead with a watt meter connected to the lead. The cooktop has power setting from 1 to 10, (or max 5 on both at once. any setting up to 6 cycles on and off like a microwave, 6 is pretty steady at about 1050 watts, 7 seven seems to be the max at 1350 watts, and 8 jumps to 1600 watts (but still ran ok for about 30 seconds till I switched back to 7. Boiled a large pot of water over about 6 or 7 minutes, all cells still sitting around 3.232 to 3.245 under load, (the battery was not fully charged prior to test). None of the bus bars leads or batteries got the even slightest bit warm either. BTW the two smaller wires on the bus bars are the solar cable and the other one is the shower pump.
As per my schematic I am also going to add a small Victron Battery disconnect on the ELV side because we also run ELV lights when we are not running the inverter for bigger loads if free camping. I don't think I actually need the 250 amp relay I bought because the 200 amp BMS should handle all my loads easily.
End result? Happy Camper!
Problem now is our next holiday was to be right up the east cost to Cooktown, half the bloody country has just burnt to the ground, massive property loss, many deaths, huge wildlife loss, huge evacuations of locals and campers, and it's still going on. So we will have to wait until things are on the mend.
Hope this info is of some use, to somebody.
Cheers
Tex
