Concord Sealed Battery not holding charge.

[robert7467]

I bought this 5 years ago and only put a few hours on it. We hooked it up to a power supply when we were doing an avionics install. After having it on a 3 amp charge for 4 days, when I put it back in the plane, I turned on the master switch and watched the voltage rapidly drop to 10 within 3 minutes. I was reading up on this and people are saying to rapidly charge, with around 15 volts and that might bring the battery to life. Basically the battery needs a good workout. I have a truck with 2 batteries and I was thinking about hooking this one up as a 3rd and keeping it in there for a few days. Do you guys think this might work?

[takair]

7 minutes ago, robert7467 said:

I bought this 5 years ago and only put a few hours on it. We hooked it up to a power supply when we were doing an avionics install. After having it on a 3 amp charge for 4 days, when I put it back in the plane, I turned on the master switch and watched the voltage rapidly drop to 10 within 3 minutes. I was reading up on this and people are saying to rapidly charge, with around 15 volts and that might bring the battery to life. Basically the battery needs a good workout. I have a truck with 2 batteries and I was thinking about hooking this one up as a 3rd and keeping it in there for a few days. Do you guys think this might work?

You can try a desulfator, but very likely it will not fully recover.  I assume that the battery was not kept on a maintainer.  5 years is a good life out of a battery that has been regularly maintained (flown and kept charged). Likely hard to recover one that has not.

[larryb]

You need a new battery. I would not waste a minute on trying to fix an old battery. Who wants to scrub a flight when the plane won’t start? Who wants to get stuck away from home? If you have a continental engine the starter adapter can be damaged by a weak battery.

[Ross Taylor]

I'm no battery expert, but I believe doing a rapid charge may do more long-term (or additional) harm.  I'm pretty sure I heard Mike Busch warn against this in a discussion of jump starting an aircraft, saying that the resulting rapid charge from the alternator and VR can damage the battery.  I only have anecdotal observation on this, but our 2017 Concorde battery failed shortly after just such a jump start incident last year.  Maybe coincidence, maybe not...

[tmo]

And if changing, there was a thread about LiFePO4 batteries around here not too long ago...  EarthX

[kortopates]

See your Concorde ICA, it states the battery should be replaced when it falls below 85% of its rated capacity. Secondly it calls for 14.4 or 28.8V Constant Potential charging - so you could try that if you haven't yet. But unless you had a large load on it for those 3 minutes its not anywhere near close. Remember starting the engine is just one purpose of your battery while its more important purpose to keep you out of trouble is to give you 30-45 minutes of time to get down and land after a electrical charging failure. 

ICA http://concordebattery.com/otherpdf/IFCA3.pdf

MM http://batterymanagement.aircraft-battery.com/BatteryDocs/5-0171.pdf

[robert7467]

Thanks for the advice guys! We are going to pull the trigger and buy another battery. I have a hard time buying another battery that I only used for a couple hours. But, it is what it is!

[carusoam]

Robert,

Get yourself a modern battery charger, desulfator, maintainer... look up BatteryMinder.

It may revive the battery you have, somewhat... to get you by for a bit...

realistically the battery you have is in an unknown condition and no longer what you want for Plan A...

It can be good having a second battery around the hangar...  a great job for the unknown player...

If somehow, a battery miracle occurs... there is an official test for battery capacity... have your mechanic test the battery’s capacity... if it passes... it will make a great story on MS...

You will have saved the life a battery... and then retired it with honors...  

PP thoughts only, not a battery expert...

Best regards,

-a-

 

[Ross Taylor]

22 hours ago, Ross Taylor said:

I'm no battery expert, but I believe doing a rapid charge may do more long-term (or additional) harm.  I'm pretty sure I heard Mike Busch warn against this in a discussion of jump starting an aircraft, saying that the resulting rapid charge from the alternator and VR can damage the battery.  I only have anecdotal observation on this, but our 2017 Concorde battery failed shortly after just such a jump start incident last year.  Maybe coincidence, maybe not...

Is it super bad form to quote myself?  Like giving myself a high five?

Is the potential for damage to a battery real, in a situation like this...where a low battery is jump started and then charged rapidly (and ungracefully) by the alternator/regulator system?  Or is this an OWT and my experience was just a coincidence?

I keep my new Concorde on an "aviation calibrated" BatteryMINDer charger now.  But I do carry jumper cables and a plug, in the event we're stuck somewhere without an FBO.  What is the real risk of jump starting and then system charging a low battery?

[RLCarter]

16 hours ago, robert7467 said:

Thanks for the advice guys! We are going to pull the trigger and buy another battery. I have a hard time buying another battery that I only used for a couple hours. But, it is what it is!

Only a couple hours over a 5yr period is probably what took out your battery

[louisut]

A trickle charger like a Battery Minder is a great idea for the amount of flying you do. As for the old battery, remember you can drop it off at Autozone and they'll give you a $10 gift card for it.

[kortopates]

4 hours ago, Ross Taylor said:

Is it super bad form to quote myself?  Like giving myself a high five?

Is the potential for damage to a battery real, in a situation like this...where a low battery is jump started and then charged rapidly (and ungracefully) by the alternator/regulator system?  Or is this an OWT and my experience was just a coincidence?

I keep my new Concorde on an "aviation calibrated" BatteryMINDer charger now.  But I do carry jumper cables and a plug, in the event we're stuck somewhere without an FBO.  What is the real risk of jump starting and then system charging a low battery?

Really high charging rates are essentially "cooking the battery" which is very harmful to it, which is exactly what you're doing when you jump start a dead aircraft battery. You could literally boil the electrolyte out of the battery doing that to the old non-sealed battery's.

Real early in my aviation career I didn't think twice about it myself. But I was a slow learner and did some stupid things. One of them included even pulling my dead battery at an FBO and getting a fast charge to get me going x-country - literally across the country from NJ to CA. Problem was the battery didn't take much of charge at all and wasn't airworthy just like our OP's battery. But this was not a very bright choice on my part as I was very inexperienced pilot departing into less than VFR weather that went front from day to night time. After dark, I had most everything on including the pitot heat and even a an old  Weatherscout  radar. The battery was so far gone that the electrical load between both my panel load and the battery that was sucking up juice since it wouldn't really take a charge was exceeding the alternator output.   So shortly after dark with the higher load, the cockpit went dark at night with some layers of clouds below me. Not the kind of an excitement I want to repeat. Then there were future events I should have known better - but I was a slow learner. But later I took off with a very weak battery at night (very stupid!) that wasn't holding a charge only to get airborne and then went to raise the gear. Before the gear finished coming up, the cockpit , lights and panel all went dark. It was pitch black out there in the desolate area, no moon, no city lights to light up the area,  and I could barely make my way back to find the airport and land by just the beacon. No longer had a radio to re-activate the runway lights. The worse part on that one is I really scared my passenger wife.

So after repeated stupidity on my part I have finally learned. I will never takeoff with a dead battery again, jump started or otherwise. And I'll do every thing I can to avoid killing it completely by attempting to start it up an engine with a near dead battery.  Perhaps some one might learn from my mistakes without need to repeat.

So fast forward to many years later for how I deal with these circumstances now in a similar situation. We were down in Mexico at an airport with no services other than fuel and we arrived back at the airplane to find the battery was very weak. After my wife turned on the master we quickly discovered why - the overhead lights had been bumped on over night. Getting a jump start wasn't possible with a 24V system and no APU on the airport, so being an A&P I went to plan B and went over the hand prop procedures I was about to do with my pilot wife at the controls. Within a couple of try's I had our Continental started up (our engines are easy compared to the big DC-3  P&W Radial engines I learned to hand prop in A&P school). So as much as I hated charging up my battery using my planes alternators, we sat their on the ramp with the engine running and most everything off while the battery charged  and I could see the load on the load meter come down from about 45 amps to start to a more reasonable 15 amps with avionics back on. We were lucky, because the battery was in excellent condition, about a year old, and we didn't entirely kill it trying to start up on a weak battery. In about 20 minutes the charging rate had come down to a near normal rate showing that the battery was taking the charge. If it hadn't we would have spent the night and probably another night before I could have gotten a new battery down there. But since we would be flying through IMC conditions the second half of the trip and landing back in San Diego in rain with low ceilings and we sure didn't need to depart without seeing the battery charge back up. As it turned out that battery lasted just a bit over 5 years - not bad. I've had other experiences where I wasn't so lucky in that 20 minutes on the ramp didn't show the battery was charging so we did shutdown and spent the night to properly correct before departing.

But in addition to frying the battery, the other thing I personally hate to do is to run the alternator that hard to charge a dead battery. As every aircraft owner knows, they're very expensive to replace and service. I have no direct data to prove it, but I can't help imagine I am  at much greater risk of taking out an alternator prematurely running it at 3 times its normal output to charge a dead battery. 

Edited May 12, 2020 by kortopates

[Ross Taylor]

Thank you @kortopates - that response and information demands more than simply hitting a like button...very much appreciated!  In my case, I picked up our E in Virginia and had to get it jumped by the cart to start - then I merrily flew to Arkansas.  I may have cooked our not-too-old battery in the process.  I now carry jumper cables connected to a 3-prong power plug, only for use at a remote or unoccupied strip.  If I need to jump start, I'll do so knowingly.

[robert7467]

Thank you for the information it is very valuable! We have a new battery on the way, but the avionics guy said its perfectly acceptable to hook it up to my truck as a power supply so I can test while I wait for the battery to come in!