Dave Solberg is a leading expert in the RV industry and author of the “RV Handbook” as well as the Managing Editor of the RV Repair Club. Today he discusses lithium batteries.
I am considering changing to a lithium battery for my house battery. No solar, just the factory setup. I will change out the charger for lithium. Will my truck have any problems with that? —Chuck
Got your question and it falls in line with another question I got recently from staff at RVtravel.com. Go Power sent them a new lithium battery to “demo” in their Winnebago class A. They wanted help with information on how to set the inverter and wondered if the charger was compatible.
Fortunately, Winnebago has all their construction schematics available online so we were able to get not only wiring diagrams, but exploded view schematics showing where the charger is and the part number.
I was able to find the specific floor plan and locate the charger and the inverter part numbers. The inverter is a Xantrex ProXM 1000 and only runs to a few outlets located in the kitchen and living room. It is not large enough to be a charger, so it does not need to be “set” for lithium as it only receives 12 volts and “inverts” to 120 volts.
Go Power only offers one model of Lithium 100 ah battery, the Sun Cycle GP-LIFE40P-100.
I talked with a technician at Go Power!, and he indicated the battery had a maximum charging capacity of 14.6 volts, as shown on the upper left of this battery. So the charger must not have a “boost” or bulk initial stage charge that would exceed that.
I found the charger in this unit was a Magnatek 7455BT that is owned by Parallax. I contacted their technical department and found this was a special charger formatted for Winnebago that produces a 13.6 volt charge for 8 hours. This means it will not harm the lithium battery; however, it also means it will not charge it to maximum capacity.
If in doubt, contact electrical expert Mike Sokol
This prompted me to contact my “go to” electrical guru, Mike Sokol, as he has conducted exhaustive research on various lithium batteries and charging options.
What I did learn was this type charger will only charge the battery to about 70%, so they would not get the full benefit of the expensive lithium battery. However, it would provide much more power than their current situation of two 12-volt batteries that originally started out as 100 amp-hr to provide 200 amp-hr, but can only be used to 50%, AND… are sulfated beyond useful operation. Lithium batteries can be drawn down to almost 0%.
The options are to get an inverter/charger that matches the voltage for the lithium battery or get a solar system with the proper charge controller. Go Power is a good option for both.
So in your situation, Chuck, I would suggest checking your charger to see what the output is and make a decision on either staying with what you have or upgrading the charger. In that case, I would suggest either Parallax or Progressive Dynamics, and make sure it matches the voltage.
Another question is how much are you going to boondock? In the previous case, they will not be dry camping for much more than an overnight stop at a rest area, so the expensive lithium is a waste of money, in my opinion.
You should not have any issue with your truck. But keep in mind your system should have a charging feature as you drive down the road – from the truck charging system to your house battery.
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