Changing AGM battery orientation?

stereoman405

I'm looking at getting some lightly used Absolyte IIP's. (A very high end sealed AGM.) These things are mammoths weighing in at 700lbs each so I'm limited in my storage options.

They are basically a large flat rectangular shape with their posts on the ends and have been oriented as such for 2.5 years. I would like to orient them so that the post are on top instead (essentially have them resting on their butts).

Is there any harm that can be caused to do this? I realize they will be very 'tippy heavy' this way, but I'll make sure to design heavy duty brackets accordingly.

westbranch

Re: Changing AGM battery orientation?

S-man, the units are quite stable once arranged in a 12 v or greater V configuration. Stability increases with the number of cell-rows connected. It is not the connections between the cells but the frame being bolted together. Here is a pic , sorry I couldn't locate the manual online. you can see the frame bolting in the pic. http://www.solarhome.org/browseproducts/GNB-6-90a09-6-Cell-12v-Absolyte-IIP-Industrial-Sealed-Battery.HTML

The reason for the horizontal configuration is that the electrolyte will not 'optimally' wick to the top of the ~24 inch height of the cells.

There is a small loss of capacity in the long term by having them upright, I noticed this when I had mine upright. Seemed to come back (marginally) once on their sides.

HtH
Eric

stereoman405

Re: Changing AGM battery orientation?

Unfortunately I'm pretty limited on space up at the cabin so the only real way I can figure out to put these things is tipped up with the posts upright. Sounds like you're saying its doable, just not ideal.

Am I risking permanent battery damage / shortness of life, or just diminished capacity? Diminished capacity I can do since these are probably overkill anyways....

stereoman405

Re: Changing AGM battery orientation?

PS - Looks like those manuals specify that horizontal is the only way to set them up, but then says you can go vertical in a "single cell 50G configuration"..... What the heck does that mean?? :grr

BB.

Re: Changing AGM battery orientation?

Pretty much everything in the solar RE system is bullet resistant... You are not going to hurt a well designed system with "improper" operation (too little sun, too much load, etc.).

EXCEPT FOR THE BATTERY.

• Most batteries probably die from under charging / over discharging (aka deficit charging).
• Storing/operating lead acid batteries below 75% state of charge for weeks/months at a time--sulfate hardening will kill battery capacity.
• Over Charging--Boiling batteries dry and/or too much "equalization" / high voltage charging. Causes water loss, positive grid corrosion, and erosion of plates. AGM's/Sealed batteries are very sensitive to overcharging because if they vent, the water/electrolyte is lost forever.
• Poor maintenance/bank layout. Wiring problems, poor parallel wiring layout, unknown bad cells (opens/shorts) buried somewhere in the bank causing loss of bank capacity/unknown discharges.

Read the Battery FAQ's--they are very helpful:

Deep Cycle Battery FAQ
www.batteryfaq.org

I like a Battery Monitor and Hydrometer (if flooded cell)--as well as an accurate DVM. If you have lots of parallel strings--a DC Clamp Amp Meter would be very handy for monitoring string heath (check for balanced current flow during heavy charging/loading).

In the end, too little charging and too much (relative to charging/state of charge) load is not good news for the battery bank. For your needs--a backup genset + charger is probably mandatory.

Still can be a good idea... Run the genset (under 50% load or a bit more) for a few hours every few days--and use the batteries for 24x7 quite low average power use.

-Bill

crewzer

Re: Changing AGM battery orientation?

50G info.

VRLA batteries are not EQ'd in the conventional FLA sense, which helps to mix up and de-stratify the electrolyte. Accordingly, they are usually built/installed in a a rather short vertical dimension. This helps keep the electrolyte from stratifying (higher/heavier SG at bottom, lower/lighter SG at top) which can destroy a battery's plates.

HTH,
Jim / crewzer