Why are airplane batteries terrible?

[EricJ]

Just now, RobertGary1 said:

But still wild to think about a small car battery at about the same weight is 690 CCA. Or a motorcycle battery at a fraction of the weight and size is 200 CCA.
Maybe aircraft batteries are 1970's technology due to certification costs. I bet the experimental guys don't use these batteries.

-Robert

It's not that wild once you consider the requirements differ considerably for each.   I'd go down the list but I think the items would be pretty evident to most here.   Yeah, some of the experimental folks can and do run non-av batteries, but many run Concordes or Gills.

 

[Hank]

2 minutes ago, RobertGary1 said:

Yea, I was just noticing the red. 5 lbs lighter than the Concorde and double the cranking amps

https://www.optimabatteries.com/en-us/redtop-starting-battery/25

-Robert

So how long would it last in your plane, running your full panel, if the alternator went out? I'm a genuinely curious CB.

[EricJ]

FWIW, Optima reds used to be pretty common in the CB racing community, and I ran them in my race cars (and other vehicles) for many years.   Their reliability and quality started going to crap, and while I stuck with them for a long time because of their soft-fail characteristics (i.e., they were less likely to strand me with a sudden failure on a hot day), the prices were going up while the quality and longevity was going down.   Then I had a couple fail suddenly, without a soft-fail, and so I lost all my reasons to use them.   They eventually got replaced in all of my vehicles as they failed out, and I've never had any desire to go back.  Personally I would not put one in an airplane, especially not knowing how it would behave across repeated significant pressure changes.

I have no experience with yellow tops, but they've been around forever, too, and they're also just an AGM battery. 

 

 

 

[carusoam]

7 hours ago, ArtVandelay said:

Let me guess...you use a battery minder.

So it appears Concordes last a long time when treated like love ones: on a battery minder.
Gills don’t last long, when not on a battery minder (for some reason they aren’t loved).

Lesson is not Gill is worst than Concordes, but aircraft batteries are fragile and requires a battery minder.


Tom

Gills have their own branded Gill battery minder....

Gill batteries die in year two... even with the special extra expensive battery charger...

I’ll sell the battery charger if you are interested... 

Best regards,

-a-

[ArtVandelay]

Gills have their own branded Gill battery minder....
Gill batteries die in year two... even with the special extra expensive battery charger...
I’ll sell the battery charger if you are interested... 
Best regards,
-a-

My Gill lasted 3 years, my Concorde 2.


Tom

[Andy95W]

My Concorde is about 8 years old.  It has never been on a battery tender of any type.

I do fly regularly and I have a modern voltage regulator from Plane Power that is adjustable for voltage.  I have mine set for 14.1 volts.  Charging voltage actually varies from about 13.9 to 14.2 depending on temperature.

I wonder if those who are reporting poor life with Concorde batteries also have poor performing old voltage regulators.

This is from Concorde's service information manual:

[RLCarter]

10 minutes ago, Andy95W said:

I wonder if those who are reporting poor life with Concorde batteries also have poor performing old voltage regulators.

Also if they are flying long enough to fully charge the battery after start up, the starter is a huge draw on batteries 

[Jerry 5TJ]

Several vendors are offering small and light Li batteries for experimental aircraft.

A few Li chemistry batteries are certified for turbine aircraft.  Many Cessna Caravan have been converted, for example.

The True Blue TB17 is a fine looking 28V Li certified battery that's about the right size to replace long-body Mooney batteries --  TB17 Datasheet

The TB17 battery is approved for installation into the Bonanza A36.    It costs about $6,500 list, tho it should last for a long time compared to a lead-acid battery.    

[ArtVandelay]

My VR is set to 13.9V and I fly a minimum of 45 minutes usually. So that’s not the issue. It was down for engine overhaul for 4 months, otherwise the plane is active.


Tom

[RobertGary1]

10 minutes ago, ArtVandelay said:

My VR is set to 13.9V and I fly a minimum of 45 minutes usually. So that’s not the issue. It was down for engine overhaul for 4 months, otherwise the plane is active.


Tom

Is this a modern Concorde battery or the wet type you can add water to?

a lot of local dealers like the wet type because the shelf life before you add the water/acid is longer  

-Robert

[jaylw314]

3 hours ago, RLCarter said:

Also if they are flying long enough to fully charge the battery after start up, the starter is a huge draw on batteries 

If you crunch numbers, it's not.  Even if the starter used 360 amps, running it for 6 seconds should only draw 2 amp-hours.  That's less than 10% of battery capacity.  If you have an alternator that puts out 70 amps, in theory it would only take a couple minutes to restore that power, although in reality it will take longer because it won't pull 70 amps.  I notice on my ammeter before starting the typical load with everything running is about -15 amps, and right after starting it climbs to +5 amps, so I figure the battery is charging at around 20 amps.  After about 10 minutes, it returns to zero, which seems to fit the numbers (at least within the same ballpark).

[ArtVandelay]

Is this a modern Concorde battery or the wet type you can add water to?
a lot of local dealers like the wet type because the shelf life before you add the water/acid is longer  
-Robert

Concorde AXC


Tom

[carusoam]

9 hours ago, ArtVandelay said:

My Gill lasted 3 years, my Concorde 2.


Tom

What battery will you go with next?

How do you feel about being in the minority of Concorde experience? 

 

Best regards,

-a-

[Andy95W]

50 minutes ago, carusoam said:

What battery will you go with next?

How do you feel about being in the minority of Concorde experience? 

No kidding.  I've never heard of anyone- until now- with Art's experiences when operated the way that he does.

 

2 hours ago, ArtVandelay said:

My VR is set to 13.9V and I fly a minimum of 45 minutes usually. So that’s not the issue. It was down for engine overhaul for 4 months, otherwise the plane is active.


Tom

I feel your pain, Art, batteries ain't cheap.

Are you reading voltage directly, or through something like a JPI engine monitor?  There can be some losses from the main bus to the avionics bus, so your actual charging voltage could be much higher.

Other than that, I'm at a loss.  Please let us know if you ever find any resolution.

[ArtVandelay]

I feel your pain, Art, batteries ain't cheap.
Are you reading voltage directly, or through something like a JPI engine monitor?  There can be some losses from the main bus to the avionics bus, so your actual charging voltage could be much higher.
Other than that, I'm at a loss.  Please let us know if you ever find any resolution.

I have 2 ways I can measure voltage: JPI and USB outlet plugged into the cigarette lighter, they both agree, both get it off the main bus.
The Gill AGMs are back ordered thru end of September.
Still deciding, did I get a lemon, or do Concordes simply require being tendered if sitting? Did the 4 month layoff cause this? When left sitting for a week, it struggles to turn the engine over, if just a few days, it seems ok. And no, I’m not leaving the cabin lights on. I’m due for my annual next month so before I replace it I will check to make sure I don’t have a parasitic drain.


Tom

[Hank]

@ArtVandelay something isn't right. I had a 10-week annual this year, a four week wait then three weeks at MSC on a ferry permit [Jan through June this year]. No charging, no tender; my Concorde AXC has always crunk right up! Just turned 3 years old and going strong.

[carusoam]

At annual... clean all the connections...

light corrosion has a way of showing full voltage, but not allow the full amperage to flow... (appearing like an ill battery)

Then again... at annual, the battery is going to see a capacity test... that will show its health...

Best regards,

-a-

[RobertGary1]

1 minute ago, Hank said:

@ArtVandelay something isn't right. I 

Batteries are a lot like light bulbs. Some last years some last days and no one can tell which will last longer. 

 

[jaylw314]

47 minutes ago, ArtVandelay said:

I have 2 ways I can measure voltage: JPI and USB outlet plugged into the cigarette lighter, they both agree, both get it off the main bus.
The Gill AGMs are back ordered thru end of September.
Still deciding, did I get a lemon, or do Concordes simply require being tendered if sitting? Did the 4 month layoff cause this? When left sitting for a week, it struggles to turn the engine over, if just a few days, it seems ok. And no, I’m not leaving the cabin lights on. I’m due for my annual next month so before I replace it I will check to make sure I don’t have a parasitic drain.


Tom

Trying to stick an ammeter in line with the battery seems tricky, but doable if you have one.  As an alternative, next time you're expecting the plane to sit for a week, try disconnecting the battery ground terminal.  If there is a parasitic circuit somewhere, you should notice a difference.

[ArtVandelay]

Trying to stick an ammeter in line with the battery seems tricky, but doable if you have one.  As an alternative, next time you're expecting the plane to sit for a week, try disconnecting the battery ground terminal.  If there is a parasitic circuit somewhere, you should notice a difference.

I have to replace the battery anyway, so when I disconnect the battery, I will hook up my multimeter and do some definitive testing. In theory the master relay should prevent this.
The only parasitic circuits bypassing the relay is the cabin switch and possibly the clock keep alive circuit, yes?


Tom

[jaylw314]

16 minutes ago, ArtVandelay said:

I have to replace the battery anyway, so when I disconnect the battery, I will hook up my multimeter and do some definitive testing. In theory the master relay should prevent this.
The only parasitic circuits bypassing the relay is the cabin switch and possibly the clock keep alive circuit, yes?


Tom

That and any unknown mucking around by previous owners... 

[EricJ]

17 minutes ago, ArtVandelay said:

I have to replace the battery anyway, so when I disconnect the battery, I will hook up my multimeter and do some definitive testing. In theory the master relay should prevent this.
The only parasitic circuits bypassing the relay is the cabin switch and possibly the clock keep alive circuit, yes?


Tom

That's worthwhile.   It's how I found that the avionics shop had wired a current-sucking clock directly to my battery, which would go dead in about five days.

[RobertGary1]

8 minutes ago, EricJ said:

That's worthwhile.   It's how I found that the avionics shop had wired a current-sucking clock directly to my battery, which would go dead in about five days.

Sounds like a bad clock. That's how its supposed to be wired.

-Robert

Edited September 11, 2019 by RobertGary1

[EricJ]

1 minute ago, RobertGary1 said:

Sounds like a bad clock. That's how its supposed to be wired.

-Robert

Not when it has its own battery.   Plus it was a bad clock.   Just a bad install for a number of reasons.   My hangar fairy rehabbed my LC-2 and that got put back in to solve the problem.

 

[Igor_U]

Years ago my dad had a 2nd car at the vacation place... it would often have a weak or flat battery after few weeks or month sitting idle.

Eventually he disconnected the clock and it never happened again. It turned out stock clock would drain it; perhaps being bad. YMMV.