Battery Upgrade

[Roadrunner]

After our first weekend camping, I think we need a new battery. Recently we installed the Intellipower 9100 and over the weekend the battery got very hot and there was a smell of sulfur. Looks like the battery (previous owner not even sure of age) probably got cooked. I'd like to replace with AGM or gel cell. What is Airstream using in their new trailers? I am also going to order the Wizard microprocessor to help monitor/maintain the battery. For those that have upgraded their batteries, what did you do? Thanks!

Bob
TAC PA-5

[Lumatic]

I put in Intellipower 9245 and an over size Universal 4B 200 amp hour AGM battery about 3 years ago. I have been satisfied with this combination but learned after the fact for optimum performance the converter should be matched with the battery. In this case it is a good match but not the best. I also learned after the fact that Universal in a Chinese battery. No complaints, but if I knew this ahead of time I would have gone with the more expensive Lifeline. You might check in with Randy at bestconverter.com on the specifics. The charge wizard is very handy.

[Steamy1]

I went with a new Progressive Dynamic (Intellipower) four stage charger/converter, then went with two (2) Lifeline (made in USA) 220 amp 6-volt batteries wired in series.

Works great. Randy had recommended the Universal, trying to save me a few dollars, but the connectors were too tall and I wanted "Made in USA" batteries. I sent the Universals back and exchanged for the Lifelines.

The 6-volt seems to be the way to go, though you do have to raise the height of the box about an inch.

[bryanl]

Hot battery, sulpher smell, and other such things do indicate a battery problem. Best to replace.

As far as cost efficiency, stick with a wet cell lead acid battery. AGM batteries are nice but for normal RV use they tend to cost about twice as much for only one and half times improvement. Gel Cell batteries are better for UPS applications and don't do well in RV applications.

Make sure you have the chargewizard for the 9100. That equipment will provide an excellent battery maintenance capability for your batteries between RV outings.

Buy your batteries from a reputable retailer who sells a lot to folks like you and will stand behind his warranties.

How long your batteries will last depends, more than anything else, on how you use and maintain them. Don't discharge below 12.0v (measured after no significant charge or discharge for at least a half hour), recharge promptly with that 9100 and chargewizard, keep out of the heat, and let the chargewizard maintain the batteries between outings.

[Roadrunner]

Bryan, if our AS is not connected to AC for an extended period of time (1-2 months), should the battery be removed and connected to trickle charger. I did speak to the service manager at a large RV dealership and he suggested the wet cell lead acid battery as well...so did the local Airstream service manager. Thanks!

Bob

[bryanl]

A battery sitting will slowly discharge. AGM's tend to discharge at a slower rate than wet cells. This is why they need a maintenance charge as a discharged battery will sulfate and that is how they age.

Trickle charging and float charging is 'old school.' In the last ten or twenty years, better methods have been developed to maintain batteries during storage. The key is to not only provide a full charge (but not too much as it can corrode the plates) like the trickle or float charge, but also to do something to inhibit or reverse sulfation.

I have seen 2 methods for inhibiting sulfation during storage. One is based on a Home Power magazine article from about ten years ago. It is the one used by BatteryMINDer(tm) products and circuits for build-your-own are on the I'net. The other is the approach used by PD's Charge Wizard or the WFCO converters.

If you can find some way to connect the RV to power during storage, the 9100 plus Charge Wizard is very convenient and effective for battery maintenance. If not, then you balance the inconvenience of getting the battery to where it can be properly maintained with the time it would otherwise sit. I'd probably put this balance at about a month or so - longer in winter, shorter in summer.

I am evaluating a BatteryMINDer(tm) solar charge controller for storage off grid. With the 100 watt panel, it should keep the battery in shape as well as provide for the fan I use to keep the Airstream ventilated.

[got2go]

AGM's are the way to go: approx. limit of discharge is max 1% per month; good to about 40 below zero; you can draw them down to nothing and they'll bounce right back (traditional lead-acid batteries are 50% killed if drawn down to zero). you can recharge them thousands of times; virtually vibration proof and maintenance free.

Costly? Yes. But, you get what you pay for.

[bryanl]

re: "you can draw them down to nothing and they'll bounce right back" -- sorry. AGM's, like all lead acid batteries, will suffer if deeply discharged. LOOK AT THE DATA and not the hype! The cycle vs life curves I have seen are similar for AGM and wet cell, just offset a bit.

You don't need the vibration or the positional capabilities of an AGM in RV's. You can find maintenance free elsewhere but even a properly used and maintained wet cell doesn't need much attention. All RV batteries need a proper vented battery box.

The lower self discharge rate can be an advantage if you are storing batteries and just cannot provide proper storage maintenance. You will still have a battery sitting and sulfating, just not as fast. The key here is that the inability to provide proper maintenance means you are going to be increasing costs in shorter battery life no matter what kind of battery you have.

re: "Costly? Yes. But, you get what you pay for" -- not by any objective measure I have seen when it comes to AGM's for RV's. Cost is about twice and benefit about one and a half best I can tell.

AGM's are nice batteries but let's not exaggerate the niceness, what say?

[got2go]

bryan - good points but I was looking at it from the op as a type of "insurance".

Replaced my traditional lead/acid with an AGM in my last boat and it removed a LOT of the issues I had with power alarms; etc.

If I can afford to do it, I'm going with AGM.

Valid criticism though - ALL batts need some type of conditioning maintenance.

[Roadrunner]

Well I finally got around to pulling the battery this weekend. To my surprise I found it to be an automotive battery made by/for KIA. Sears checked the battery and it is definitely gone. Was also told it is a wet cell but sealed. So I guess there is no way to top off the battery. Are these common? Also noticed the battery box is cracked on the bottom from front to back...no wonder we had water coming in around the battery box. It looks like I will be replacing both the box and the battery. In addition, I'll be ordering the charge wizard for our intellipower 9100. Thanks for all of your input!

Bob
TAC PA-5
WBCCI - 4871