Downside of Battery Minder

[DonMuncy]

Lately I have come across situations where planes which are constantly hooked up on a Battery Minder have experienced battery problems. The battery begins to fail, but the Battery Minder keeps it charged up until you go somewhere and stop your plane, only to find it won't start again.

I think I/we need to have a periodic check to ensure the Battery Minder is not masking a problem. Maybe once every couple of months one should disconnect the Battery Minder and turn on some current draw equipment for a half hour and then crank it to see how it does.

Thoughts? 

[tony]

yup

[carusoam]

Makes good technical sense.

But so does buying a $300 charger/conditioner from Gill...

OK, I may be out on a limb here. But I did it anyway...

First piece of data... The Gill charger was unable to revive my first dead gill lead/acid battery. I bought the charger and a new battery at the same time... Really out on a limb.

Second piece of data... The Gill charger was unable to revive my friend's gel cell Gill battery.

Third piece of data... One gill battery is three years old and the other is one. The older is not as strong as the newer... As in, they live with the paired charger but are still aging terribly.

In the long body, two battery system, one battery is float charging while the other is being used/charged normally.

What keeps dissimilar batteries from screwing up this system...?

Staying on topic...

My batteries go on charge once a month. Overnight. I think they would be susceptible to the same challenge as staying on the charge continuously. One wouldn't know how strong the battery really is in this case.

Going off topic, again...

Fortunately, Autozone gives a $5 credit so I don't have 15 dead Gills in my garage...

Fortunately part#2, with a two battery system, I feel better about such a lame link in the chain...

Disappointed, my favorite engine supplier is the same company as Gill, TCM.

Best regards,

-a-

[Piloto]

I think it depends on the battery type (lead/acid vs. AGM) and the charging voltage. I found that AGM batteries like the Concorde are less susceptible to the problem because they will charge to a higher voltage thus reducing current flow. Lead acid batteries will not charge as high thus they have current flow which reduces capacity. AGM does not need battery minders. AGM batteries are the ones used now in the auto industry.

 

José

[yvesg]

My battery minder is a solar panel giving very low current. I only use it from fall till spring. This helps for cold temperature diminished capacity. I started using this after I almost cancelled a flight where we had to boost the airplane from the car. With the solar panel, this has not happended again. It follows me wherever I fly. If the aircraft sleeps in a hangar away, its temperature will normally be higher than outside so the battery will be OK.

Yves

[triple8s]

I had been told that about battery minders, give you a false sense that your battery was in good shape only to get you away from home and stranded. The best way to keep a battery up ? Fly the plane often.

[rbridges]

I have a 14v system, so I'm just using a float charger I bought at Lowe's years ago.  My concorde battery is nearly 4 years old and appears to be doing well.  How it compares to new, I don't know.  The gill battery it replaced was 3 years old (according to the date written on its side) when it lost a cell, and it was kept on a charger, too.

[N601RX]

If your using a Concorde battery I don't think there is any need for a battery minder, unless your not going to be flying for a several months. These batteries have a very low self discharge rate, if they are draining down enough to have a noticeable affect on cranking, then something is wrong with the battery, or their is something on the aircraft draining them. The other possibility is the voltage regulator is not set correctly to keep them fully charged.

[rbridges]

If your using a Concorde battery I don't think there is any need for a battery minder, unless your not going to be flying for a several months. These batteries have a very low self discharge rate, if they are draining down enough to have a noticeable affect on cranking, then something is wrong with the battery, or their is something on the aircraft draining them. The other possibility is the voltage regulator is not set correctly to keep them fully charged.

 

wasn't aware their discharge rate was different, but that's good to know. 

[mooniac15u]

AGM batteries are susceptible to overcharging so a standard battery minder can potentially cause damage.  They also have a slower discharge rate so keeping them charged is not as much of a problem.

[chrisk]

I'm sure this has been discussed before.   The battery minder does not seem to work when I plug it into the jump start port on my plane.  I end up having to take off the battery access, remove the cover, and then connect it.  --Which means, I don't use the battery minder very often. 

 

Is there an easy (and hopefully legal) way to get the battery minder connected without having to remove the battery access port and cover?

[mooniac15u]

I'm sure this has been discussed before.   The battery minder does not seem to work when I plug it into the jump start port on my plane.  I end up having to take off the battery access, remove the cover, and then connect it.  --Which means, I don't use the battery minder very often. 

 

Is there an easy (and hopefully legal) way to get the battery minder connected without having to remove the battery access port and cover?

 

The battery minder won't work through the jump start port because there is a relay on that circuit that needs to be activated in order to connect the circuit to the battery.  You would need a traditional power source to activate the relay.  Of course the battery minder won't be able to do it's job even with the relay active because the relay will put a constant load on the charger.

[ArtVandelay]

AGM batteries are susceptible to overcharging so a standard battery minder can potentially cause damage. They also have a slower discharge rate so keeping them charged is not as much of a problem.

There is a special battery minder for AGMs, I think the model # 12248 AA S5

[carusoam]

For fun...

A 24v battery external to the plane will hold the relay closed while charging the two batteries in the plane.

Best I can tell, it worked overnight...charging all three batteries. Too complex, with too many unanswered questions, with too few recommendations in the POH...

Realistically, my mechanic offered to wire in a float charger with the plug coming to the same area behind the door of the external connection point. Open the door and connect to one battery..?

I still open the access panel if I need a charge...

Best regards,

-a-

[helitim]

"Realistically, my mechanic offered to wire in a float charger with the plug coming to the same area behind the door of the external connection point. "

This is how my system is set up. Seems to work well so far.

Tim

[kortopates]

Battertyminder has been selling an aircraft wiring accessory to enable your mechanic to make a quick install of a cable extension from the battery to a plug that you can plug the batteryminder in without opening anything up. The current version they have uses aircraft (FAA) approved wire and plugs and terminal, but the plug is pretty bulky and hard to fit in the usual locations - which have been the TKS or O2 port door, or APU plug door or even just on the Hat Rack by the baggage door with a small hole in the hat rack. Installation is generally a minor mod.

 

Also as Teejayevans noted, they make different aviation specific models specific to the battery, thus for the Concorde Sealed battery, they want you to use the S5 series with thermal sensor. Theoretically they are voltage tuned and temperature sensitive so as to not harm the battery if left on continuously. Many folks have bought a Batteyminder without getting the aviation specific version for their battery type, and I recently noticed that they are now allowing you to send in your unit to get it converted to the aviation specific model.  See their website for details http://www.batteryminders.com/ and send it end to get yourself absolved of all your past charging sins Maybe it'll even prolong the life of your battery which seems to be getting increasingly more expensive!

 

FTR, I leave my charger on continuously going on now about 3-4 years and doing great. But I also got 6-7 years each on my prior 2 Flooded Gills which seems to be impossible reading any thread on Battery's here. They worked great for me, but they did take maintenance on a quarterly cycle unlike the sealed battery's to keep them going. 

[mike_elliott]

There is a special battery minder for AGMs, I think the model # 12248 AA S5

your right, there is a specific battery minder for Concords (S5) and a specific one for Gill (S2) 

Concord is donating a battery as a door prize for the Mooney Summit Oct 24-26, and VDC Electronics is donating a Battery Minder. I have used both in my F and never had a battery issue.

[slowflyin]

+1 for the Concorde and S5.  Leave it on all the time and starting year four of service.   We will see.

[BobAustin]

I have the Battery Minder installed with the aircraft temp probe.  I have two 14V Gill G-35 mounted in extreme rear of my 201/Missile.

 

The fluid level is only checked at annual because of the limited access.   I leave the Battery Minder connected all the time.

 

 Using Don Muncy's suggestion I left the Battery Minder off for two weeks and sure enuf the plane would not start.  

 

After overnight charging it started right up.  Batteries are about a year and a half old !  Previous Gills also lasted under 2 years.

 

Guess I need Concords at annual in December.  Any suggestions ?

[cliffy]

Each type of battery (AGM, flooded cell, niCad, etc) has a specific charging voltage and method. It can be found on the paper work included with each battery when purchased. Batteries residing in the tail cone seem to have a longer life than those in the engine compartment (DUH, you think heat might be a problem?)

Engine starting actually uses very little of the capacity of a good battery so if it won't start the engine it is really a DEAD battery and its CAPACITY when "charged" again is in doubt. The only way to really tell is to do a "Capacity Check" per the manf directions (also included with every aircraft battery when new).

The more often you find your battery dead,the lower the capacity will be when recharged. If it dies in 2 weeks its time to replace it. It's a dead duck, not to be trusted, even if recharged. 

Think about this- You come out for a flight and the battery is "dead as a door nail" (Shakespeare) , you jump start the engine or a quick recharge to get enough to start and you go fly. What if you loose you alternator now? How long will that battery last?

I've seen this many times over the years. Just thinkin' 

[tpapilot]

What about vibration? Are the airplanes that have long battery life dynamically balanced? I'm a new 201 driver and was curious if vibration is hard on all part or mainly the electronics.

[Andy95W]

I guess this falls under "to each his own", but I don't really understand why you would want to use a Battery Minder, or Battery Tender, or whatever. I've owned 3 airplanes over a total of 22 years and I have bought a total of 3 batteries, so I guess I average 7 years per.

And I have never had a dead battery and never used a battery minder. I do fly 3-7 times per month for at least 30- 40 minutes each flight, but that's not really all that special.

For the last 11 years I have used exclusively Concorde RG batteries and have my voltage regulator set at 14.1 per the Concorde guidelines and brochure.

[DonMuncy]

Wouldn't you know it. After I started this thread; it happened to me. My Concorde RG died, and I didn't know it until I flew away from home and it sat overnight.

I contacted both Concorde and Batteryminder. Neither of them gave me any help.

If I flew more often, I probably wouldn't need to worry about it, but until then, what is our collective judgment about how to utilize the Batterminder, but still be assured the battery is in good shape.

Help me formulate a plan.

Once a month, disconnect the BM, turn on the landing light for 20 minutes, come back tomorrow and see if it cranks over normally?

Hint; on my recently ruined battery, the unloaded voltage was 12.3, but hooking up my 12v air compressor and listening to it struggle for 10 seconds and the voltage dropped to about 7v.   

[ArtVandelay]

I would just periodically turn on the BM, you can use a 24 timer to turn it on for an hour per day, that should be more than enough

[ArtVandelay]

I just replaced my Gill, it was old but seem ok, try a hot start and it failed, when they go it can be quick