Battery Maintainer

RyanB

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Does anyone use a maintainer on a regular basis?

If so, why or why not?
 
I keep my Commander plugged in everyday that she's in the hangar. The Concorde specific battery minder keeps your battery fresh and topped off.

From the web page...

Will the BatteryMINDer extend the life of my battery?
Yes! The BatteryMINDer's desulfation circuitry prevents and eliminates Lead Plate Sulfation. This is the leading cause of battery failure.

What is Sulfation?
Sulfation is the build-up of lead sulfate crystals. Batteries develop sulfate naturally over time, especially if they are left discharged. This leads to loss of cranking power, longer charging times, shorter running times, and a dramatically shorter battery life.

How does BatteryMINDer Reverse Sulfation?
The BatteryMINDer desulfator battery charger uses high frequency electronic pulses (which is different from high voltage). Unlike other pulse type chargers, VDC's BatteryMINDer use a range of high frequencies. This ensures both old and newly forming sulfate will be safely dissolved in the shortest possible time.
 
I don’t use one all the time but will use one periodically, especially when the airplane has sat for a while. I’ve been impressed with the battery minder brand charger/maintainers. They seem to do a good job.
 
Same as GaryM, I have a Concorde battery and the this maintainer. Pretty cheap in the grand scheme of things, and I have power in my hangar, so seemed like a reasonable thing to do.
 
I use a BatteryMinder on my PA-32. Works great. I keep it plugged in when not flying so I always know she's ready to fly. I can also play with the avionics in the hangar without fear of draining the battery. I bought the optional connectors kit and had my A&P install the lead so it is in the GPU port on the empennage. Makes connecting very convenient.

Edit: added photo
20210315_144332907_iOS.jpg
 
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I had one in the flight school and salvaged a few batteries with it. Batteries that had been drained flat when students left the master on overnight. That's a real good way to sulfate that battery and ruin it. The battery desulfator was able to knock most of the sulfate back into solution, though I don't think you ever get it all, especially the sulfate that has fallen off the plates into the bottom of the cells.

The other way to make a battery last a long time is to avoid overfilling it when topping up. If it's not on charge and you top it up to the split ring, it will boil off some of the acid, and besides making a mess on the belly of the airplane, you'll then top it up with distilled water, diluting the acid and weakening the battery. If it's not on charge, just fill the cells to halfway between the tops of the plates and the bottom of the split ring. Both Concorde and Gill will tell you this. When charging, the electrolyte heats and expands, and it also gets bubbles in it that increase its volume.
 
Whatever you decide to do, make sure you use the CORRECT battery maintainer for your battery type. Flooded cell and AGM batteries may require different charging profiles, and battery MAINTAINERS have the correct float voltage for maintenance, while CHARGERS may overcook your battery and boil out the electrolyte.

Having said that, AGM batteries (e.g. Concorde) have very low self-discharge rates compared to flooded cell batteries, and will tolerate 2-3 months of non-use with very little harm. Self-discharge rates of AGM batteries can be as low as a few percent per month. Flooded cells can discharge as much as 2-4% per week, depending on the ambient temperature. I don't use a battery maintainer, but I do keep an AGM battery in the airplane. With my flying frequency, even in the winter, it is enough to keep the battery in good shape.

The downside of an AGM battery is if you let it go flat, it is likely ruined unless you properly recharge it within 24-48 hours. Even then you may have to know some tricks to get it to take a charge. Flooded cells respond to this kind of full discharge abuse a little better. Overall, it's best not to leave your master on and let the battery go flat.
 
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If so, why or why not?
Depends on why you need the maintainer. If your battery is discharging on a regular basis then there is an issue with your electrical system which should be corrected. With a healthy electrical system and following the OEM storage recommendations there may be a need for a maintainer or not. Unfortunately, some people will use a trickle charger to "fix" a problem like parasitic drain which will only continue to damage the battery and reduce its life.
 
Why? The Battery Tender and products like it are “smart chargers.” They keep the battery safely charged without overcharging. If you over charge you will fry the battery. The smart chargers, if left plugged in when the plane is not in use, will extend battery life.
 
The Battery Tender and products like it are “smart chargers.” They keep the battery safely charged without overcharging.
FYI: not all "smart chargers" speak aviation. There are a couple OEM bulletins out there that list some non-aviation chargers by name that will damage aircraft batteries due to overcharging.
 
@RyanB , as you know we keep the Mooney plugged in anytime it’s in the hangar. I don’t remember the brand, but it’s made for aircraft batteries.
 
I fly an experimental with an Odyssey battery. I have a battery specific maintainer but have never used it.

Odyssey batteries maintain a charge very well if left in a charged state and disconnected from the electrical system. From their website:
Can be stored on open circuit (nothing connected to the terminals) without recharging for up to 2 years or 12.00V, whichever occurs first.

Admittedly when the temps get below freezing I don't fly often ...
 
I have a Concorde battery and use the maintainer recommended by Concorde. Neither the battery or the battery maintainer are cheap. I keep it plugged in when not flying.
 
Itty bitty Odyssey battery to spin my 520. Never needed a charger or a maintainer including when stored outdoors all winter in AK. If you need a maintainer you need a better battery.
 
I keep my Commander plugged in everyday that she's in the hangar. The Concorde specific battery minder keeps your battery fresh and topped off.

From the web page...

Will the BatteryMINDer extend the life of my battery?
Yes! The BatteryMINDer's desulfation circuitry prevents and eliminates Lead Plate Sulfation. This is the leading cause of battery failure.

What is Sulfation?
Sulfation is the build-up of lead sulfate crystals. Batteries develop sulfate naturally over time, especially if they are left discharged. This leads to loss of cranking power, longer charging times, shorter running times, and a dramatically shorter battery life.

How does BatteryMINDer Reverse Sulfation?
The BatteryMINDer desulfator battery charger uses high frequency electronic pulses (which is different from high voltage). Unlike other pulse type chargers, VDC's BatteryMINDer use a range of high frequencies. This ensures both old and newly forming sulfate will be safely dissolved in the shortest possible time.
I’m another +1 for what Gary said. I have the same battery/setup. I had them install the quick connect in my left wing locker. Easy to pop open and plug in after each flight. Very happy with it.
 
I fly an experimental with an Odyssey battery. I have a battery specific maintainer but have never used it.
Odyssey batteries maintain a charge very well if left in a charged state and disconnected from the electrical system. From their website:
Admittedly when the temps get below freezing I don't fly often ...
Mine has sat for months for different reasons. I think I have thrown an old charger on it once or twice (did leave the master on once). On the other hand, it is only 7 years old...
 
I keep mine plugged into a maintainer with a desulfator when I'm not flying it. Unfortunately I have to keep my door partially open for that to happen. If anyone has figured out how to mount the plug externally on a Cherokee 140, I'd like to hear/see it. I have a GPU plug port but there isn't room for the maintainer plug in there.
 
On my Cessna, I connect the Concorde maintainer directly to the GPU port using the large alligator clips that came with the unit. Positive to post nearest center..ground to post closest to outer edge. On my Bonanza, I use the adapter cable attached to battery. I leave the cowling unlatched on the battery side while charging. Been doing this for years..
 
If anyone has figured out how to mount the plug externally on a Cherokee 140, I'd like to hear/see it.
With your extensive sheetmetal skills now, why not install your own external maintainer plug? Just keep in mind where you punch that hole will determine if it's a major or minor alteration. Have installed a few plug-ins: mounted small plug next to the GPU plug (if room), dedicated holes in cowling/skin, added a window vents to pass cords through, and even adapting a belly antenna cover plate with a plug...but this one definitely requires some sort of cockpit reminder when plugged in.
Can't you adapt the maintainer to the GPU plug?
FYI: you could adapt the GPU plug easily. The problem is some external power systems require a separate power feed to the GPU relay to energize the electrical system so you are in inducing a load plus running a relay for extended periods. So it depends on your electrical system whether this route will work effectively.
 
How are you guys plugging in? My battery is aft in the tail and would need to leave my baggage door open. Has anyone used a piper style “jump” plug on the side of a Cherokee with a battery maintainer?


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With your extensive sheetmetal skills now

heh heh. I doubt two access panels counts as "extensive" but I appreciate your enthusiasm. I wouldn't know where to start as in sourcing a plug, cover, etc.

Do you have any pictures of the charging ports next to the GPU plug?
 
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I don't know. Pretty sure the GPU bypasses the battery instead of charging on my Cherokee.
Guess I'm lucky, the GPU plug on the Sport goes to the master relay on the battery side. So I can charge the battery thru the GPU plug
 
heh heh. I doubt two access panels counts as "extensive" but I appreciate your enthusiasm. I wouldn't know where to start as in sourcing a plug, cover, etc.
AS pn 11-00500 $30

11-00500.jpg
 
I wouldn't know where to start as in sourcing a plug, cover, etc.
Where there's room in an existing access panel, we've used the Battery Maintainer brand airframe interface kit. Have also repurposed the old style Piper single GPU plugs/receptacles for a charger. They come with a flanged external plug that can be mounted most anywhere. For other options, since most electrical items fall under standard parts, we'd just look for an appropriate commercial connector set up and install it. Have even used 110v marine shore power type connectors/receptacles with success. So there's plenty of options to discuss with your APIA.
 
FYI: you could adapt the GPU plug easily. The problem is some external power systems require a separate power feed to the GPU relay to energize the electrical system so you are in inducing a load plus running a relay for extended periods. So it depends on your electrical system whether this route will work effectively.
Could you simply rewire the existing GPU wiring?
 
Could you simply rewire the existing GPU wiring?
According to the definitions in the FARs, any change to the primary electrical system is a major modification. That means STCs or some other approval needed. FAR 43 Appendix A, Major Alterations:

(xii) Changes to the basic design of the fuel, oil, cooling, heating, cabin pressurization, electrical, hydraulic, de-icing, or exhaust systems.
 
I installed a connector for my Battery Minder about 7 years ago and use it all the time. Mine is accessible through the oil filler door:
DSCN2038.jpg
 
If one needs a battery minder to keep the battery up, there's probably a drain somewhere as previously mentioned in this thread. Some ground-power circuits use a diode and a couple of resistors as part of the GP circuit, and I once found the diode partially shorted internally, draining the battery through one of the resistors. In another airplane I found that same resistor blown out, and checking the diode found that it too was shorted, but its shorted resistance was much lower so it passed enough current to fry the resistor.
 
I just started using one and keep it plugged up anytime it's in the hangar. I only did it because the surefly constantly uses power so I thought why not. Not sure how true it is and I'm sure it can't use much sitting but I always wanted an excuse to try one.

I used to think they were a crutch for another problem and made the battery weaker. Will see how my battery holds up because I've never had a problem with a battery before when not using one. So it will be a test for me.
 
Could you simply rewire the existing GPU wiring?
You could provided you needed to. But I wouldn't recommend it as you'd just create a different problem if you ever needed to jump start your aircraft. Easier to add a separate plug for the charger.
 
My battery is under the rear seats so that wouldn't work for me
I may have my aircraft model wrong, but isn't there access to a belly cover plate for an ADF antenna under the seat near the battery? If it's not being used why not install an MS type cannon plug with a screw on cover in the cover plate for your charger? You may have to get dirty to connect it and remember to disconnect it but it would be simple and near your battery.
Any pictures or example of small plug?
Depends how you define small. But the options can be limitless. Here are a few:
https://www.aircraftspruce.com/cate...p/menus/el/cablecableaccessories_sealall.html
https://www.andersonpower.com/us/en/resources/PowerPoleResourcesPage.html
 
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