Battery charging

kevin47881

Final Approach
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Time to fly!
The relatively new 12v battery in the Cherokee was TU when I went to the field this morning. Trying to jump it off with the tractor was unsuccessful.

In an attempt to save the battery prior to replacing, can I use the same battery charger on the plane as I do for my stuff around the house? If so, what setting is best? Trickle charge or hot charge? Maintenance free or conventional? Disconnect the battery cables?

Logic tells me that a battery is a battery but just want to make sure. BTW, it is a wet cell unit.

Thanks for the insight!!!
 
You can try to trickle charge it- about 1/2 amp-hr for 36 hours. But it's probably sulfated up the wazoo.

You should check your bus voltage when the bird is net running- anything above 14.2 V will be too much (boil off all the electrolyte).

My suggestion- if it's an outdoor bird, buy a "Solargizer" which is a pulse 40 mah battery maintainer. Put the solar panel on the glareshield, and run the wires out the doorseal into the oil hatch to the pigtail that you install on your battery (strap tie it to the oil filler). Get some proper equipment. Cheaper than batteries every 2 years.

If your charging voltage is correct, you'll have the next battery for so long you'll have to look in your logs to find out when you last replaced it.

If you have elec. power at the aircraft, use VDC's 12V battery charger/pulse maintainer.

(No pecuniary relationship with that company). Bruce
 
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Thanks, Bruce.
The bird is hangered so the solar option is out, albeit one heck of an option! I'll look into the VDC.

My charger has two options; 2 amp and 10 amp. Would 24 hours at 2 amps with the auto cutoff work?
 
You might be able to do a smidge better on price than this....there are two versions, the 12112 and 12117.

http://www.pacificbattery.com/batteryminder.html#anchor4

I have three of the older ones (12112) and two of the newer, I can't tell the difference. They go into idle mode at 100% batt. voltage, in which 40 mah pulses at the piezo resonance freq. of FeSO4.

Fort Hood uses them on the tanks.
 
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It never ceases to amaze; ask a question and within 1.5 hours answers and advice are rolling in.

Thanks, Bruce and Dave!
 
Kevin, go figure on this one the number of dead batteries in my past.

".....there's gotta be a better way......"
 
Thanks, Bruce.
The bird is hangered so the solar option is out, albeit one heck of an option! I'll look into the VDC.

My charger has two options; 2 amp and 10 amp. Would 24 hours at 2 amps with the auto cutoff work?

Probably not. If the problem is a liberal dose of sulphate in the battery, a simple charge will put a surface charge on the battery but it will not deep charge. The chargers Bruce and others are recommending use pulses of charging current to knock off the layer of sulphate so that the cells can thoroughly charge.

It is a completely different technology.

-Skip
 
In an attempt to save the battery prior to replacing, can I use the same battery charger on the plane as I do for my stuff around the house? If so, what setting is best? Trickle charge or hot charge? Maintenance free or conventional? Disconnect the battery cables?

Logic tells me that a battery is a battery but just want to make sure. BTW, it is a wet cell unit.

Thanks for the insight!!!

We use an aviation specific charger/desulfator, but I can't remember the brand, I'd have to go to the hangar and look. Bird is plugged in anytime she's in the hangar.
 
It's a VDC model slightly down floating point ($90).
The $150 models also compensate for temperature.....
 
The relatively new 12v battery in the Cherokee was TU

Relatively new?
if it is still in the warrantee period I would ctc the mfg and see what they want you to do. For eg, Gill has a salvage procedure for dead batteries as such.
 
Relatively new?
if it is still in the warrantee period I would ctc the mfg and see what they want you to do. For eg, Gill has a salvage procedure for dead batteries as such.

The battery was installed less than 2 months ago. Will contact Gill!
Thanks, Dave.
 
They go into idle mode at 100% batt. voltage, in which 40 mah pulses at the piezo resonance freq. of FeSO4.


A couple of questions if you don't mind ...

1. What is a 40 mah pulse?

2. Why do you care about the resonance of Iron Sulfate in a lead-acid battery? And what is piezo resonance?

Jim
 
A couple of questions if you don't mind ...

1. What is a 40 mah pulse?

2. Why do you care about the resonance of Iron Sulfate in a lead-acid battery? And what is piezo resonance?

Jim


1) I suspect that he meant 40 ma (milliamp), not 40 mah (milliamp-hour). Then again 40 mah would be 144 Joules which could be used to describe the energy in the pulse but I doubt that's what was intended.

2a) Probably another mis-type, should be Lead Sulfate.

2b) The Piezo effect refers to a dimensional change in a matrix in the presence of an electrical field. An object with this property will have a resonant frequency and excitation at that frequency will produce the maximum physical motion for a given excitation power. That said, I think this is mostly hype from the BatteryMinder folks as the sulphate (PbS04?) isn't likely to have any particular shape, dimension, or resonant frequency and I'm not certain it's got much of a piezoelectric property either.
 
1) I suspect that he meant 40 ma (milliamp), not 40 mah (milliamp-hour). Then again 40 mah would be 144 Joules which could be used to describe the energy in the pulse but I doubt that's what was intended.

2a) Probably another mis-type, should be Lead Sulfate.

2b) The Piezo effect refers to a dimensional change in a matrix in the presence of an electrical field. An object with this property will have a resonant frequency and excitation at that frequency will produce the maximum physical motion for a given excitation power. That said, I think this is mostly hype from the BatteryMinder folks as the sulphate (PbS04?) isn't likely to have any particular shape, dimension, or resonant frequency and I'm not certain it's got much of a piezoelectric property either.

1. And I'm not sure what a 40 mA pulse is going to accomplish, even over an extended period of time. Most desulfator designs use a rather heavy slug (> 10A) of current for a relatively short duty cycle (from <1 to a maximum of 5%) to break up the sulfate mass and get the lead oxide plate exposed to the electrolyte.

2(a). Probably lead sulfate; I was just curious to figure out how iron got into the mix.

2(b). Agreed, but in my limited experience it is only crystalline substances (quartz, Rochelle salts, etc.) that exhibit the piezo effect. Lead sulfate DOES have a crystalline form, but the common form in an aqueous solution is a white amorphous solid, not crystalline.

Jim
 
Agreed on all points.

1. And I'm not sure what a 40 mA pulse is going to accomplish, even over an extended period of time. Most desulfator designs use a rather heavy slug (> 10A) of current for a relatively short duty cycle (from <1 to a maximum of 5%) to break up the sulfate mass and get the lead oxide plate exposed to the electrolyte.

2(a). Probably lead sulfate; I was just curious to figure out how iron got into the mix.

2(b). Agreed, but in my limited experience it is only crystalline substances (quartz, Rochelle salts, etc.) that exhibit the piezo effect. Lead sulfate DOES have a crystalline form, but the common form in an aqueous solution is a white amorphous solid, not crystalline.

Jim
 
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