Battery-diff betw sealed/unsealed

Michele

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Michele
I have a sealed battery in my C176M. The A&P wants to replace it with a battery that isn't sealed. What's the difference between the two types? Which is better and why?
 
I have a sealed battery in my C176M. The A&P wants to replace it with a battery that isn't sealed. What's the difference between the two types? Which is better and why?

What is a C176M? I have had great success with Concorde AGM batteries.
 
Opps, Typo...C172M

Soo, can I just order the sealed battery from spruce or where ever and just plop it in? When I told the A&P I might want to do the job myself, he made like it was a big job that needed special tools and know-how [to install the unsealed]; something about the acid and powering up the battery and so forth.
 
When I asked the A&P about the difference between the the sealed and unsealed, he mumbled some stuff about not having empirical data, but that he didn't think there wasn't much difference.
 
Hi Michele,

Original battery for your plane is a standard lead battery that is not sealed. The non sealed ones have caps that come off and you can get to the individual cells. They also allowed leakage. What your mechanic was talking about was that these batteries will show up with the acid in a separate container and you will need to add it.

The newer style batteries are sealed and you do not need to do anything to them to get them ready to use (like putting the acid in). A style of them is called an AGM (adsorbed glass mat). I personally have great success with AGM batteries made by Concorde. The Gills I have used seem to fail sooner. I should also point out that AGM batteries do require a different charger than you use with a standard lead battery. I would use a sealed one.

Here is the application chart for the Concorde series: http://www.aircraftspruce.com/catalog/pdf/ConcordeFAAEligibility-new.pdf

It looks like you need a size 25. The unsealed is a CB-25. I would go with either the RG-25 or the RG-25XC. http://www.aircraftspruce.com/catalog/elpages/rg_25xc.php

If you want a little extra cranking power go with the XC version.

The replacement of the battery can be done by the owner under 14CFR43 but needs to be recorded in the airframe log book. Use this FAA advisory: https://www.faasafety.gov/files/gsl...Owning Your Own Aircraft [hi-res] branded.pdf

Drop us an update.
 
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Thanks gentlemen, I have all I need to defer that work until I can sort it out and do it myself. First all, I'm not convinced it needs replacing and secondly, he wants to charge $306 to replace it with the unsealed (lessor) model. I can't seem to find the current battery's log entry, but I'll look more carefully as will I'll check the battery itself for any markings that might reveal when it was installed. Frankly it hasn't given me a lick of trouble and starts up like there's a demon inside no matter how cold or what time of day or night this winter. I'll let you know what happens. Thanks again.
 
I just replaced my 182's battery myself. Put in a Concorde sealed AGM with the XC. Works great!

You can do this yourself, really. I am no uber-mechanic.
 
Some installations of a sealed battery will require a 337 and the services of a A&P with IA to execute it.
 
Some installations of a sealed battery will require a 337 and the services of a A&P with IA to execute it.

But, in this case, Michele already has a sealed battery installed...So she won't be changing anything.
 
Some installations of a sealed battery will require a 337 and the services of a A&P with IA to execute it.
And here is the paper work side of it.

She already has a 337 applying the sealed type of battery installed, thus he needs nothing but her own signature to return it to service as per 43-A Para ( c ) Item (24) Replacing and servicing batteries.

I'd stay with the sealed lots less paper work rather than submitting another 337 to remove the STC that been installed buy the guy who installed the last sealed battery.
 
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Doesn't matter what the weight is.

IF, the weight exceeds that of a "negligible" change the FAA blanket approval does not apply.

And even still a new W&B sheet would be needed, and a pilot cannot make one of those either.

So no, you can't just yank the battery and change it without a little leg work prior.
 
I just listened to a webinar on this subject. They stated that changing prop brands is a major change. Changing Battery Brands is a major change.

They stated if I took off my prop and changed it with the same brand, not a major change as long as pitch and length stay the same.Same for battery, stay with the same brand and not a major change.

Myself I do a W/B whenever I do things like this, but that is just me. I am always trying to shave weight so I like to wiegh my plane alot and see if I am reducing weight...
 
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IF, the weight exceeds that of a "negligible" change the FAA blanket approval does not apply.

And even still a new W&B sheet would be needed, and a pilot cannot make one of those either.

So no, you can't just yank the battery and change it without a little leg work prior.

I think we're in agreement. Even if your RG weights to the gram the same as the flooded cell you replaced, it may still require a 337 to be filed.
 
When I asked the A&P about the difference between the the sealed and unsealed, he mumbled some stuff about not having empirical data, but that he didn't think there wasn't much difference.

YOU MIGHT WANT TO FIND ANOTHER MECHANIC--ONE THAT REALLY IS UP TO DATE.
 
It's hard to believe such a simple question has devolved into such a serious issue as legality. I can't find a log entry for this battery and there doesn't seem to be any STC for it in my STC collection. Special rules for the Frickin battery, Geesh! Slowly...I ...turn. I feel like I'm in a nightmare.

So, at this point I need to find out exactly what is in my airplane, find out if it is legal and if it isn't, then find out what would make it legal and then do that. I really can't get to the airport until next weekend, so this will take a while. I'll provide an update when I get more intell.
 
It's hard to believe such a simple question has devolved into such a serious issue as legality. I can't find a log entry for this battery and there doesn't seem to be any STC for it in my STC collection. Special rules for the Frickin battery, Geesh! Slowly...I ...turn. I feel like I'm in a nightmare.

So, at this point I need to find out exactly what is in my airplane, find out if it is legal and if it isn't, then find out what would make it legal and then do that. I really can't get to the airport until next weekend, so this will take a while. I'll provide an update when I get more intell.

Welcome to general aviation Michele! The most over regulated, least understood activity known to the human race...
 
There are differences in the shape, size and fit of batteries that may require the battery box to be altered. These aren't AA or D batteries.
 
It's hard to believe such a simple question has devolved into such a serious issue as legality. I can't find a log entry for this battery and there doesn't seem to be any STC for it in my STC collection. Special rules for the Frickin battery, Geesh! Slowly...I ...turn. I feel like I'm in a nightmare.

So, at this point I need to find out exactly what is in my airplane, find out if it is legal and if it isn't, then find out what would make it legal and then do that. I really can't get to the airport until next weekend, so this will take a while. I'll provide an update when I get more intell.

Look at the paper work that comes with the new battery. The The concord sealed battery will have an STC included with the Instructions for Continued Airworthiness.

If you have no paper work saying the battery TYPE has been changed and you do not want to deal with the STC to make your aircraft legal, then simply order the Gill wet cell battery that came with your aircraft from the factory.
 
You guys are aware that Concorde has a PMA for the C172M, for their batteries to be direct replacement for the original?
They have an STC for aircraft that they don't have PMA, but the FAA has PMAd the Concordes as direct replacement.
 
You guys are aware that Concorde has a PMA for the C172M, for their batteries to be direct replacement for the original?
They have an STC for aircraft that they don't have PMA, but the FAA has PMAd the Concordes as direct replacement.

I understand that is for their wet cell batteries.
 
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