Battery Compartment

[Elkman]

For my part I wanted to be able to go more than 2 days before needing to recharge my RV's two house batteries using the generator and the idea of saving a couple thousand dollars which is roughly 1 percent of the cost of the RV made no sense then and does not now.

I dd not buy a new motorhome to save money or economize on our travel costs which are going to be much higher than staying at hotels and eating at restaurants. The net cost of the RV over the period of time we hope to be using it is about $20,000 a year plus $2400 a year in storage fees.

I understand about not wanting to buy unproven or rapidly changing products but this is not the case with lithium-phosphate batteries which are very close to being a commodity item.

[reo33064]

Originally Posted by Elkman

Pure AGM only means that "pure lead" is used with the glass mat. The sale pitch is that they will last for 3 times as many charge and discharge cycles (about 900) as a regular flooded lead acid battery. On the other hand there is still the issue of damage if taken below 50% SOC. The charge cycles published show only 400 cycles if the batteries are taken down to 80% SOC as compared to 2000 charge cycles with lithium-phosphate under the same conditions.

With lithium-phosphate the SOC can be brought to 10% (safety shutoff with most) and they will recharge in a third the time of a lead acid battery and they will support from 2000 to 3000 charge cycles depending on the depth of the discharges.

I love Lithium batteries. I had 2-1000 amp hour (same size as your 2-AGM's) in my Roadtrek Agile that run the AC for 4-5 hours without any generator running. Light weight, quick charge, thousands of charging cycles.

[Phil G.]

Other than the $$$ they cost ... the problems with switching to lithium coach batteries in a currently owned RV is that in addition to buying them, you have to also do one or more of the following:


1. Probably buy and install a different built-in charger/converter than what came in the RV.
2. Probably install an isolator to make sure that the lead acid chassis batteries are not directly connected to the lithium coach batteries whenever the chassis engine is running.
3. Maybe add a 2nd, or change to a much larger capacity -> engine alternator.
4. Or address both 2. and 3. above by installing a battery-to-battery charger for the lithium battery(ies).

What thousands of us current RV owners need for an easy switch to lithium coach batteries is a "true drop-in" lithium replacement for our existing liquid acid or AGM batteries that doesn't require any other system changes. I'd love to change to lithium batteries in our otherwise excellent currently owned Class C if it didn't mean messing around with other complex and/or $$$ system changes in order to use the lithiums.

(My coach's 12V Group 31 AGM batteries are true deep cycle ones and are rated for 115 amp hours each, Another AGM battery manufacturer even offers 12V Group 31 AGM true deep cycle batteries that are rated for 125 amp hours each.)