Batteries

[BobThompson]

A question about batteries. I have had an AGM bat. as a house bat. in my comm. truck for 8 years. When I need to replace those in the MH I might do the same, but has anyone investigated Lithium Polymer or Lithium Titanate? They are supposed to have twice the power per pound without the problem of thermal runaway associated with Lithium Ion. Just wonderin'. Bob T

[ottffss]

While you are technically correct, the current state of Li-xx for moho use is still a tad experimental. I'd love to switch..... But..... I'll wait just a couple more years...

BTW - AGMs can also have (very rare) thermal runaway issues... I've seen one on a Lifeline AGM and they practically came in person to get it back. The new Li concoctions have far, far less than the "older" Li blends almost to the point the new Li seem to be practically inert in that category. That is pretty nice.

Read through the following - very carefully. Have a large pocketbook handy and numerous reference gurus available. There is still a fair amount of rocket science and experimental "it's not supposed to do that" involved.

The current lithium-ion in an RV guru is Technomadia at:
http://www.technomadia.com/category/life-on-the-road/technology/lithium-ion/

[wa8yxm]

The LIthium batteries are still a bit on the expensive side, but then so is AGM in my book, considering that if your AGM lasted 8 years a cheaper flooded wet cell may well have gong 10 or more. AGM does have a few advantages in SOME cases though, Normally RV's are not on that list.

But more power per pound.. THAT... Is desierable, Very Very Desierable.

[Perry White]

Only AGM battery I run is under the seat on my Harley's. They don't last long without Battery Tender.

I use cheapest 6 volt flooded I can get and check level twice a year and spray white Lit grease on the terminals and forget about them. No corrosion and no problem. I use RO water to top off..

["007"]

I have two AGM's for house and a 10 year old starter battery that hasn't missed a start yet.
The Bird System keeps them all fully charged with coach plugged into house outlet.

[Luv2go]

I've taken the plunge. Here's a quote from an unrelated post regarding my experiences with them:

...and my coach batteries are 400AH total of Thundersky lithium iron phosphate batteries. The chassis battery is the original Motorcraft Lead Acid.

I used to have 1000AH of cheap AGM lead acid batteries as coach batteries, but their capacity was badly degraded after only a few seasons, so I replaced them last spring. I suspect I killed them by letting them get sulphated (still have them, are desulphating them and will be using them in a solar energy system in our house).

The nice thing about the Thundersky batteries is that they weigh about 180lb instead of 1000lb so the coach is now underweight again. I get more usable energy out of them as the old lead acid as they can be 80% discharged 3000 times before you lose significant capacity. I would only discharge my old batteries about 30% before recharging them and they still only lasted 3 years! They also have a great charging profile, taking max amps until almost 100% charged and do not require an absorption stage.

The bad thing is they cost over $2k (for 400AH at 12V) and they are only available from small EV (Electric Vehicle) suppliers, the one I used with was hard to deal with and would not recommend, his web page is no longer up so I assume he went out of business. Also they like to float at 14V, which should be a little high for the lead acid chassis battery when the BIRD connects them together. So far I've not had to water the chassis battery so maybe it's not.

Note I would not have used these if I could use flooded lead acid batteries, but I chose to install the batteries in a location that was good for weight distribution on the coach, also it would have been difficult to properly vent them and impossible to check electrolyte level.