Battery recovery

Homebuilt Aircraft & Kit Plane Forum

Help Support Homebuilt Aircraft & Kit Plane Forum:

BJC

Well-Known Member
HBA Supporter
Joined
Oct 7, 2013
Messages
13,735
Location
97FL, Florida, USA
I have an old 12 volt Concorde lead acid battery that has been out of service for several years. It is down to about 2 volts.

Is it possible to recharge this battery? Any special techniques?

Thanks,


BJC
 

plncraze

Well-Known Member
HBA Supporter
Joined
May 11, 2006
Messages
2,115
Throw it on a charger and see. Several years is quite a while for the plates to sit in the acid at the bottom. If it has the caps that you can leave off watch and see if all the cells bubble. If you have a charger it is free and you have nothing to lose.
 
  • Like
Reactions: BJC

Kiwi303

Well-Known Member
Joined
Jul 22, 2015
Messages
418
Location
En Zed. Aka The Shire.
There are battery reconditioners out there, they essentially eat the lead sulfides off the surface of the anodes leaving bare lead plate again. best used in conjunction with new acid.
I don't know what's on the market there, but just google battery reconditioner fluid, some chargers have a desulfator cycle option as well.
 

TFF

Well-Known Member
Joined
Apr 28, 2010
Messages
15,634
Location
Memphis, TN
You might get something back, but it will be a iffy. I hate batteries as they like exercise even if you don’t want to use them. Keeping track of shelf batteries is a pain. I don’t care how good a battery tender is, you still have to exercise it or it will still go bad. I have not had much luck with the conditioners doing what they say. But if you go talk to the concord rep at Oshkosh, he will tell you the founder would throw old car batteries from his collector cars from dead and bring them back. Best I can do is get about $6 in lead scrap at the battery shop.
 

Martin W

Well-Known Member
Joined
May 14, 2021
Messages
80
I am not offering recommendations .... just relating my experiences.

I bought a 1949 Packard that had not been started for over 10 years .... it had been parked outside during hot summers and freezing winters. Battery was dead of course ..... but I could not easily find a replacement that weekend .... it was 6 volt ..... long and narrow (6" X 18) the type that was often used on old farm tractors of that era.

Impatient to hear the engine run I put the battery on a slow charge for 24 hours .... amazingly it held a full charge , it started the car and I drove it for 8000 miles and sold the car years later and that battery still worked like new.

.......

Had a 3/4 ton Suburban 4X4 .... battery was only 2 years old but went dead and would not hold a charge .... my elderly dad said the bottom plates could be shorting out from the sulfide residue settled in the electrolyte .... so out of curiosity I (very carefully) drained out the old solution and while the battery was upside down I (carefully) aimed a garden hose up into each cell and flushed it out .... a whole bunch of grey sediment came out ..... replaced it with new electrolyte and that battery was like new again and gave service for several more years until I updated to a larger one.

My old dad was a farmer and every fall he would bring all his machinery batteries into the basement and keep them on trickle chargers and keep them at 14 volts .... he said a fully charged battery is "dormant" .... whereas a low battery constantly eats away at the plates trying to keep the charge up ..... his batteries usually lasted 10 to 14 years

....

That's all I know and its not very much.
 

TFF

Well-Known Member
Joined
Apr 28, 2010
Messages
15,634
Location
Memphis, TN
That’s one thing you can’t do with a sealed battery, drain it. All those Gills you had to buy acid for, can also be drained for storage until needed. Kind of a pain to store acid, bad acid. That’s what you would do if you had a good old fashioned bomb shelter.

Fully charged being draws no current if hooked up to a charger. Older batteries that won’t fully top off will boil off trying to get that last bit,or worse really boil. Playing with the acid takes all the fun out though. “I”got a 24v Gill in a friend’s helicopter dying right now. Replacement cost is close to $3000. I hate batteries.
 
  • Like
Reactions: BJC

BJC

Well-Known Member
HBA Supporter
Joined
Oct 7, 2013
Messages
13,735
Location
97FL, Florida, USA
I”got a 24v Gill in a friend’s helicopter dying right now. Replacement cost is close to $3000. I hate batteries.
I hear you, Tom.

My son-in-law installed a new Concorde 24 volt battery in my Cessna A152. It went bad in less than 10 hours. Aircraft Spruce replaced it at no cost, but it kept me from a planned trip. I would like to meet the Cessna employee who thought that it made sense to use a 24 volt battery in a 152.


BJC
 

Martin W

Well-Known Member
Joined
May 14, 2021
Messages
80
I bought a 1949 Packard Deluxe Eight Touring Sedan for my wife, who loves classic cars, circa 1975.

Thanks for the battery info.


BJC
Cool .... sounds like the same car I had ... now if only I could have found a wife like yours who liked classic cars .... haaaa !!

Mine was black , 4 door sedan , straight 8 with a 3 speed standard transmission , true highway car , could cruise all day at 65 mph , that engine was so smooth and quiet you could not hear it running at idle. It was originally bought new by a doctor and he said Packards were a couple notches above Cadillac in those days .

Sold it in the early 1980's to raise money for training on the Bell 47 helicopter.

Which is the complete opposite of smooth and quiet transportation.

Then my wife filed for a divorce .
 

BJC

Well-Known Member
HBA Supporter
Joined
Oct 7, 2013
Messages
13,735
Location
97FL, Florida, USA
My wife’s was green, and had an overdrive. It was a weekend driver, although she did drive it to work (High School special education teacher) occasionally. We sold it rather than renovate it.

Her daily driver, including going to work, for over ten years, was a Boxster. She’s now driving a RS 350.


BJC
 

Martin W

Well-Known Member
Joined
May 14, 2021
Messages
80
Further to long term battery storage .... I write this from memory , and advise folks to make sure it actually works.

Our local fire department has 6 units with diesel engines and double 12 volt batteries in each .... I was friends with the chief and we often had lunch together. Somehow our conversation turned to batteries.

He said a constant paranoia was a firetruck with a dead battery when the alarms came in .... and it happened sometimes even if the batteries were not that old.

He said they had purchased a special battery charger to solve the problem .... apparently a 12 volt battery is actually about 13 volts and if you keep it charged to about 13.5 volts it will last much longer in storage .

Like I said , I am no expert , so do some research .... the information came from the battery charger salesman who set it up .... it was a sensitive (precise) charger that attained a precise voltage.

Sounds a lot like what my dad did with his fleet of batteries .... he checked the specific gravity monthly and kept them charged right up all winter. His oldest battery was 15 years but my young brother borrowed it to test drive a hot-rod project ... no battery box or tie-down and the battery fell thru the wheel opening and smashed on the street.
 
  • Like
Reactions: BJC

wsimpso1

Super Moderator
Staff member
Log Member
Joined
Oct 18, 2003
Messages
8,347
Location
Saline Michigan
I can vouch for the reconditioners working on keeping batteries useful longer and even recovering one with a shorted cell. Our local FBO has been using them on all their working airplanes for six years now, claims doubled battery life. We have one on The Trusty Archer and it seems to have extended battery lives. When I first got one for the house, it took a battery on the tractor that would not fully charge (almost assuredly a shorted cell - 10.8 volts after running on a charger) and fixed it.

The desulfating pulse is a diminishing amplitude high frequency AC pulse - I am guessing it burns any solids free of the plates before they bridge the plates, but I do not know if really does anything for rejuvinating the chemistry of the battery. The battery starts with one plate set of lead, the other of plate set of lead with lead oxide, and sulfuric acid between them. Exactly how this high level of order diminishes, reducing capacity and ultimately shorting a cell, I do not know, but it occurs. I do know that solids fall out of the either the plates or the acid over time, and they take acid (where the great bulk of the energy is stored) out of the mix, so capacity must diminish with solids falling out...

I knew a smart engineer that swore you could usually fix a battery with a shorted cell with a jumper made of a lamp cord and two alligator clips. Set it up on the battery, then go around the corner (in case anything untoward happens to the battery) and very briefly plug in the other end. Another very smart engineer I know heard of it and now swears by the technique. Neither of them are electrical engineers nor battery specialists, and nor am I, so take this all with a grain of salt. Supposedly the 110 VAC would burn any bridging and allow a full charge again. The problem with this idea is that if battery is making significant solids - they are bridging the plates - the battery does not have far to go before it happens again, and the slowly accumulating diminishment of in the battery capacity to crank the engine or power the rest of the system continues unabated.

This very old battery? Toast is my guess, good only for a trade-in on a new one. These batteries slowly self discharge to lead sulphate equally distributed to both plate sets and dilute sulphuric acid between them - which is a dirty and choatic state chemically, and prone to resisting return to charged condition.

Knowing all this about the battery, I suspect that a long sitting battery will will not be rejuvenated by simple acid replacement and a charge - both plates are messed up too, so capacity and cranking amps will be but a shadow of its former self. Maybe charging it as fully with a reconditioner, then replacing acid will recover some of its capabilities. As for rinsing out the battery, I would not attempt that. First is the hazard with the acid. Second is that most tap water is chlorinated and has other imputities likely to poison the system. De-ionized water, like out of reverse-osmosis filter, will have better odds, but compared to a trip over to the auto parts emporium and trading the old one and one Benjamin for a new one, well, I would do the later.

Billski
 

Aesquire

Well-Known Member
Joined
Jul 28, 2014
Messages
2,979
Location
Rochester, NY, USA
Draining and flushing and fresh acid can resurrect a lead acid battery that doesn't come back with just a charge, sometimes.

Another little trick is to drop the battery evenly, carefully, about a foot onto a flat firm surfsce, like a driveway, to break any bridging precipitate. It's weak & porus. Have a hose handy with fresh water and pick a location where if you crack the case the mess is washable and the diluted ( handy hose! ) acid can be safely splattered and hosed away. So NOT by the wife's prize roses or a car! Battery acid is nasty but far down the list of environmental hazards and lots of rinsing will dilute it to harmless so don't be stingy on the hose. ( urine is low PH too. a sewer is fine. Baking soda can help clean area. )

Often a cell shorts because the precipitate builds up to the bottom of the plates, filling the gap deliberately built into a regular lead acid battery. Agitation, draining and rinsing may help. Yes, the plates are eroded, but can keep working quite a while until they turn to lace too delicate to take engine vibrations. ( or road shocks )

Keep in mind you Do look like a Bubba! Watch this! Video when you drop batteries deliberately. For a good reason. ;)
 
Top