Maintaining your Batteries

[joshua32064]

I have heard many people comment about how important it is to maintain the water level in your batteries and keep your batteries charged.

This may sound like a stupid question, but if you do not keep your Airstream at home, what is the best way to keep your batteries charged?

I assume that you could always take a generator to the place where your Airstream is sitting, but how long do you have to let it run while attached to the batteries?

Is a Solar panel a viable option? What else can be done to maintain the batteries if you are not out on the road with your trailer for a month or two?

Thanks.

[jcanavera]

I did some study on this topic last year when I found my battery dead on my Safari after 60 days of unuse. What I found was quite revealing. With the master disconnect switch on, and all appliances off I found a draw of .10 of amp.

Considering my battery is an 105 amp hour unit, I could understand why it had insufficent power to run the power jack after 60 days.

Turning the master disconnect off, with the only draw being the propane detector, the draw is .09 of an amp. A figure more more tolerable. When the trailer goes into long term storage in the winter, I pull the battery and take it home.

Here is the complete thread on the subject. http://www.airforums.com/forum...=&threadid=879

Jack

[joshua32064]

Jack,

Thanks for your response. It certainly seems from the thread that you listed in the e-mail, that if I am not going to be using my trailer over 30 days, it would be best to attach some sort of Solar device to maintain the batteries.

Since your original thread, what have you done? Have you tried the Solargizer or Battery Minder?

[joshua32064]

I went to the Pulse Tech web site to get some more information about the Solarizer Solar Charger. If anyone is curious, Pule Tech is the manufacturer of the Solarizer Solar Charger.

From what I see, I can either go with the 5-watt 1/2 Amp model or the 10-watt 1 Amp model. The one thing that the site does say is that these units hook up to 1 12-volt battery or up to 4 four batteries in parallel.

I guess my first question would be, are the Airstream batteries hooked up in parallel? Do you think the 5-watt model is ample to simply keep my batteries charged when I am away from my unit for an extended period of time?

[Silvertwinkie]

Someone posted this a little bit ago. These seem awfully handy......plus the CCD 25' and the 25' Safari I believe have 2- 12v power plugs inside (cig lighter like connections).

http://cgi.ebay.com/ebaymotors/ws/eB...tem=2435689837

Eric

[nds]

I ran across this on the Airstream Links Site.

Phred's Poop Sheets (section on batteries)

I haven't read all the way through it, but what I have seen of his material, he appears to know his stuff. Hope it helps.

[jcanavera]

Originally posted by joshua32064
Jack,
Since your original thread, what have you done? Have you tried the Solargizer or Battery Minder?

I did neither. I just make it a policy turn off the master disconnect switch when I store the trailer between trips. At this point I've been out every 30-45 days since April so the battery still has ample charge to operate the power jack to allow me to get the trailer in the the home driveway.

Once I go into my 6 month winter storage, I remove the battery and bring it home.

I think the real education for me was the amp draw when the the disconnect switch is left in the on position.

Jack

[George Jr.]

Jack,

On my 88 Excella, if you operate the cut off it will blow line fuse in the radio. I have to remove line fuse first. Have you encountered?

[gvanman]

Batteries 101
Let's start at the beginning...
Everybody seems to think that a battery is a battery is a battery.
In reality, batteries are manufactured for 3 types of application:
1) Automotive SLI (Starting, lighting & Ignition).
2) Motive Power - forklift trucks, golf carts, etc.
3) Network Power - standby systems, backup power, etc.
The difference in these applications is like day and night - you have to use the correct battery type for the required application. If you don't, then you won't get the performance from the battery and will be frustrated and/or disappointed.
This is what the applications are designed for:
1) Automotive - Lead Calcium alloy which gives a high current for a short amount of time allowing you to start your engine and run auxiliary loads for a short time. This is not a deep-discharge battery and will not survive too many of these.
2) Motive Power - Lead Antimony alloy which can be repeatedly discharged to 80% of its rated capacity and will give you a good life cycle in this application. In industrial use, this type of battery is designed to give 80% of its rated capacity every day and a life of about 5 years.
3) Network Power - Pure lead or various alloy mixtures which are designed to be float-charged to keep them at full capacity in anticipation of power failures. This type of battery is not designed for deep-discharge cycles and has an expected life of 10-20 years.
There are slight variables to the above 3 applications, but generally, this is what they are designed for.
My general impression is that people are using type 1 - Automotive batteries and expecting them to perform like type 2 - Motive Power batteries in their Airstreams.
That is why I have a problem with battery information websites, such as Phred's - they are too generalized and not focused enough on the application. I am not picking on Phred here - his site is quite good compared to the plethora of other similar sites out there!
Let's take an example such as jcanavera's obsevation:
His battery was unable to allow him to use his power jack after 60 days. I don't know what type of batteries are in this particular application, but assume (dangerous, I know) that they are automotive type. If they were Motive Power batteries, then they still would have been over discharged after 60 days because of the 0.10 amp parasitic load on the battery. The batteries were stated to have a capacity of 105 AH. Using the 80% rule, this gives an available capacity of 84 AH. The parasitic loads give a daily draw of 2.4 amps, so the battery can only provide this for 35 days before the battery is fully discharged to 80% of capacity. Any further load after this time will deeply discharge the battery. An important point here - over discharging a battery at a very low current is much more damaging than over discharging a battery at a high current! If, as I suspect, this was actually an Automotive battery, then it would have been toast much sooner!
Here's a tip when buying a battery - look for the capacity to be stated in AH (Ampere Hours) at the 6-hour rate (C6). This usually indicates that it is designed for cycling duty as per type 2 - Motive Power. Also ask for the cycle life at the 6-hour rate and expect this to be at least 300 duty cycles. Type 1 - Automotive batteries are usually rated at the 20-hour rate (C20) or only show CCA.
Hope that somebody finds this useful.
Cheers,
Dave Harris

[jcanavera]

Originally posted by George Jr.
Jack,

On my 88 Excella, if you operate the cut off it will blow line fuse in the radio. I have to remove line fuse first. Have you encountered?

No.

Jack

[john hd]

Originally posted by jcanavera


No.

Jack

YES!

leave the univolt pugged in and open the battery disconnect, goodbye radio fuse.

been there done that.

john

[dscluchfc]

Ok....so what is the proper way to do this to not blow the radio fuse...I keep blowing my fuse if I am plugged into shore power, but it is all ok if I am boondocking.

How do you work it to not blow the fuse?

[jjonesnc]

Dave, Thanks on a great post on Batteries! I am sure it will be very useful to many!

[davidz71]

Joshua,
I've had the Pulse Tech Solargizer 5 watt model for over 2 years. I've left my trailer for over a month at the hunting site and no electricity. The batteries are used from Friday noon through Sunday noon and then charge with no use until the next Friday. The 5 watt seems to have them topped off when I return on Friday. It is hooked up to one of my 105 amp hr. Delco Voyager batteries but the other is charged at the same time due to the way they are wired. The 5 watt should keep it charged but if in doubt go with the 10 watt if you have any parasitic appliances. Oh heck, just unplug them. I've been impressed with the Pulse Tech product. Also check www.batterymart.com for the BatteryMinder solar charger maintainer.

[wingfoot321]

George Jr.,

My 1987 manual states that plugging the trailer into 120 volt power withthe master switch off will blow radio fuses and may damage other 12 volt components. The master switch is meant to be used when storing the vvehicle for long periods of time.

Apparently, the master switch is only to be used to isolate the battery when unplugged. The above is almost a direct quote from the manual.

[TomW]

My owner's manual does not specify anything about the battery. I figure when I finally get a battery (major repairs in process right now) I will look for one that fits the footprint of the battery tray, and follow gvanman's advice on the proper type.

Does anyone else's owner's manual make a specific recommendation? If so, what is it?

Thanks,
Tom

[gypsyartist]

I'm new at these forums, and can't seem to find where to post a question.
I have a 2007 19' Safari Bambi . When the batteries ar e put on store mode something is draining the batteries. I know the batteries are good when i connected a different battery and it too was drained in a day. The dealer said there have been problems with the LP gas detector draining it so I have disconnected it to see if it could be the drainer. I also disconnected a power wire connected to the water filter that had a tiny red blinking light when everything was supposedly shut down. This seems like poor design if the LP gas detector is draining the battery. I know I can disconnect the cables, but isn't that what the "store battery switch"is supposed to do? Any body have this problem?
I've read some of your battery storage suggestions and found all the info helpful. I have a solar panel to maintain the batteries, but I really suggest having a Honda generator as a piece of mind back-up. With the current mystery battery drain situation and having the power jack going dead on me, I just whip out my handy Honda generator and abra kadabra, POWER. I have the 1000w, but highly suggest springing for the 2000w. I keep it in my truck bed tool box all the time.
Sooo, back to my problem of the constantly drained batteries, anyone have the same problem?

[Relentless]

Yes, I had that problem. The solution is don't unplug the brake breakaway plug. That's what I did. Since the brakes are electric, when I pulled the plug the brakes set and drained the batteries within 24hours, even with the battery disconnect switch off.

Please don't ask me why I did that. It took a service tech about 5 min. to figure it out. Your batteries should last a minimum of 3 weeks in storage with the disconnect switch off.