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Odyssey battery toes up?

R

rv9aviator

Well Known Member
My friend left his master switch on on his RV-4 a couple of weeks ago and after charging for a few hours it only shows 5.5 volts. It is only 2 years old but I'm afraid he ruined it. When I put my digital charger made for AGM batteries on it, it shows a fault light. Any suggestions on reviving it.
 
My -680 croaked for 'no apparent reason' and I took it to an Odyssey dealer. They charged it up and it's been fine ever since. Didn't see what they used...
 
Another dead one...

Timely.... I went to the airport yesterday and found I did the same thing (I really need to start leaving the strobes ON - although I do have a warning light)! I applied some power for an hour and it was back up to 11.7v, which started OK, although a bit slow. I'll see how it holds up then think about getting a new battery.
 
rv9aviator said:
My friend left his master switch on on his RV-4 a couple of weeks ago and after charging for a few hours it only shows 5.5 volts. It is only 2 years old but I'm afraid he ruined it. When I put my digital charger made for AGM batteries on it, it shows a fault light. Any suggestions on reviving it.
Click to expand...

I left the master on for ten days (!!) and was sure my three year-old PC680 was a goner. A standard charger couldn't put anything into it, but out of desperation I left it on a little battery tender (2A) overnight and it came back. The battery is now six years old and still going strong. Amazing.

Try different chargers until you find one that the battery can accept.
 
I left two batteries dying in a field for two weeks. Totally dead. Not the first time I killed them dead, either (master). Put them on a "stupid charger" and they charged up fine. 1.5 years later, both are a little weak, but still serviceable.
 
I'll try that. I have several trickle chargers that I can see if one will work. I also sent an E-mail to Odyssey to see if they had a procedure I could try. Thanks!
 
Great timing

Mine somehow drained itself this weekend.

ZERO on the gauge.

Put on charger for 15 minutes.

Worked fine.

Let it sit overnight on the charger and make sure
you have a good contact.
 
Walt said:
You need a high current charger to kick it off.
Click to expand...

That's been my experience. Good old fashioned charger. I've had success with 10+ amps. Smart chargers, trickle chargers and "maintainer" chargers have not worked for me, not when the battery is DEAD.
 
DocThrock said:
That's been my experience. Good old fashioned charger. I've had success with 10+ amps. Smart chargers, trickle chargers and "maintainer" chargers have not worked for me, not when the battery is DEAD.
Click to expand...

Seems like "smart chargers" need to detect a battery is present before they will begin to start charging. This is done by sensing voltage at the battery terminals - if it's dead there's no voltage. My Battery Tender is definitely this way: When I connected it to a dead battery it didn't even detect it was connected. I had to use, as Matt said above, an old-fashioned "dumb" charger that applied voltage whether it's connected to a battery or not. If the battery has been discharged for some time it undergoes sulfation which further impedes the ability of the battery to take charge - it takes time to break the sulfation down. I've seen a dead battery draw almost no current when first connected to a battery charger; after a few hours it started to draw more current and overnight it appeared to be fully charged.

Mark Olson RV-7A F1-EVO Rocket
 
I initially purchased a 2/10A agm smart charger from Auto Zone. One evening it read 16.1V while charging my 680 aux bat. I then purchased the recommended Odtssey 12A charger. It will only hold about 80% charge now, even after several cycles. Max recommended charge volts per Odyssey= 15 V.

They seem a little fragile to me.
 
I put a 1 amp old fashioned trickle charger on it and the voltage just keeps creeping up. It is at 10 volts and rising. I bet by morning it be almost back to normal. It will be interesting to see if it stays charged and will crank the engine OK. I didn't try a bigger charger at first because I didn't see the reply suggesting that. Once it gets back to normal I may run the desulfate program on the digital charger.
My son told me you can put a little 9 volt battery in line with the charger so it will read some voltage and that will let the newer type charger go ahead and charge a dead battery. Once it starts charging you remove the 9 volt battery. Glad I put a master low voltage warning light on my 9A so hopefully that won't happen to me. As soon as I shut down and the alternater stops charging the light comes on and blinks.
 
I think you're doing fine with the trickle charger: the increasing voltage is a good sign.


Mark Olson RV-7A F1-EVO Rocket
 
rv9aviator said:
I put a 1 amp old fashioned trickle charger on it and the voltage just keeps creeping up. It is at 10 volts and rising. I bet by morning it be almost back to normal. It will be interesting to see if it stays charged and will crank the engine OK. I didn't try a bigger charger at first because I didn't see the reply suggesting that. Once it gets back to normal I may run the desulfate program on the digital charger.
My son told me you can put a little 9 volt battery in line with the charger so it will read some voltage and that will let the newer type charger go ahead and charge a dead battery. Once it starts charging you remove the 9 volt battery. Glad I put a master low voltage warning light on my 9A so hopefully that won't happen to me. As soon as I shut down and the alternater stops charging the light comes on and blinks.
Click to expand...

I put a LOUD audio transducer in parallel with the low pressure warning light. :D It has a kill switch for those times I want to work on the plane with the master on.

Your experience with the little charger is exactly what I saw. Stay with it, bet the PC680 will come back and provide good service.
 
DocThrock said:
That's been my experience. Good old fashioned charger. I've had success with 10+ amps. Smart chargers, trickle chargers and "maintainer" chargers have not worked for me, not when the battery is DEAD.
Click to expand...

I have done this with the 10A charger, but I was careful to only leave it on for a short time, about 15 minutes-----dont let the battery get warm to the touch.

After that initial charge, switched to the smart cube charger and it worked just like normal.

As was stated, the smart chargers need to see a bit of voltage in the battery to begin functioning.
 
Quick PC680 ?

There are several variations on EBay with various prices? What are the differences and which is best for the RV?

Thanks
 
Grant, seems just like my order. I heard about them from someone else here so whoever that was gets the credit.
 
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battery tender rocks

I have a 2a and 5a battery tender. While building, I drained my PC680 down below 6v over and over while messing with the panel. Battery torture. The tender always brought it back to 100%. I used that same battery for 3yrs in the plane, and just replaced it this year.

I've also used these tenders to bring back 1000a Optima batteries from fully drained. Takes forever, but these battery tenders are amazing. Over time I've bought more of them for lawnmowers and other batteries. They pay for themselves by making batteries last longer.
 
Joined the club. Actually I think the hangar cat or someone else flipped on the BATT switch. After work yesterday I went to do an evening mountain swoop looking for elk, But NO! dead PC680 apparently I left the switch up 10 days ago when entering a flight plan in the GPS (then got weathered out before I even started the engine).

So tried the Odyssey battery tender...no go(flashing red). Ran home got the ol' Sears charger I've had since high school. Hooked up the clamps and plugged her in. Meter didn't budge, but it was humming like always trying to do something. I went next door for a cup of joe, 20minutes later I checked it...TaDa 4amps showing. I removed ol' reliable and plugged in the Smart tender. Solid red light means its putting out a charge. we'll see in the morning.
 
You can jump start these "smart" chargers by connecting another battery in parallel for a second. I have an old battery (12V motorcycle battery) laying around the shop for this since I leave my master on more than I care to admit. I've tried it on my battery tender and a larger smart charger from Walmart. I can't remember the brand, but its orange FWIW.

I've been meaning to try the jump start method with a small 9V just to see if it will work, but I haven't gotten around to it yet.

Greg
RV-7
 
aviation consumer article.

Interesting timing. In the most recent issue of Aviation Consumer, there's a great article on battery chargers. I am a happy "BatteryTender+" customer, but AC didn't even review them because it is an "automotive charger". The article speaks highly of BatteryMinder. Hmmm, my PC680 is not an aviation battery. It is an AGM battery and the BatteryTender+ is designed for AGM, so it's unclear to me if I should really expect more from an "aviation charger" also designed for AGM. There is a hint below in the Odyssey docs at a perhaps one difference.

Going further, Odyssey documentation recommends <shock> their own branded battery charger and cites some reasons why below. The good news is that their name branded charger is no more nor less expensive than others. See below.

"Standard automotive type chargers are not designed to return 105-108% of the energy removed. They normally boost charge to 80-95% and expect the alternator to complete the charge. Chargers listed on our website at www.odysseybattery.com are specifically designed for ODYSSEY batteries that are routinely deeply discharged. They provide the 105-108% recharge and then switch to storage charge."

So heck, even though I very happy with my batterytender, I'm wondering if I'd be 10% more happy with an Odyssey or BatteryMinder product. Thankfully I have enough battery started devices that it's not a waste for me to buy another and move the old chargers to a new spot.
 
Nah, there are lots of 'smart' chargers that will top off your battery using a slightly higher voltage and then drop down the voltage to a 'float' level to maintain it indefinitely. The charger you have is fine, save your money.

Erich
 
Argh, I killed it

I have a PC680, 2.5 years old.

I left my master on.:(

I used a sears 10/2 amp charger, took 2 hrs at about 4--6 amps indicated to get enough in it to start the engine. Then flew for 1.5 hrs. Alternator started out charging at about 25 amps, quickly dropped to 16 amps, then slowly over time, dropped to the normal 2 amps or so.

Battery seemed fine for about 2 weeks. Now, most of the time, it won't accept any charge from the aircraft alternator, and the alternator voltage floats high (like 15.3 v or more) but shows slight battery discharge. Sometimes, by putting some load on it, like turning strobe lights on, the battery will then accept the charge, the alternator drops to normal 14.7 or so, and battery charges at 16A for awhile, then slowly drops to normal 2A or so.

But later, the battery is down to 10 volts again.
it is a plane-power alternator.

I just ordered a new PC680
 
Odyssey 680

It seems that the Odyssey battery needs a bit different charging current and voltage than the normal wet cell or even the mat type batteries. Check the web site and you will fine that info. I had problems with a discharged Odyssey 680 until I got the Battery Minder Odyssey specific charger. With that the old battery recharged well and also the new 680 I bought after giving up on the old one. The old one was sold and still running fine, the new one also stays charged with this charger.
 
scsmith said:
I have a PC680, 2.5 years old.

I left my master on.:(

I used a sears 10/2 amp charger, took 2 hrs at about 4--6 amps indicated to get enough in it to start the engine. Then flew for 1.5 hrs. Alternator started out charging at about 25 amps, quickly dropped to 16 amps, then slowly over time, dropped to the normal 2 amps or so.

Battery seemed fine for about 2 weeks. Now, most of the time, it won't accept any charge from the aircraft alternator, and the alternator voltage floats high (like 15.3 v or more) but shows slight battery discharge. Sometimes, by putting some load on it, like turning strobe lights on, the battery will then accept the charge, the alternator drops to normal 14.7 or so, and battery charges at 16A for awhile, then slowly drops to normal 2A or so.

But later, the battery is down to 10 volts again.
it is a plane-power alternator.

I just ordered a new PC680
Click to expand...

I was sure I had killed mine several years ago. I left the master on for ten days (!) and the battery was totally flat. The only way I could get it to take a charge was with a small 2 amp "dumb" charger which I left on overnight. Next day the battery was back up and it has been in service since. The PC680 now has 6.5 years on it.

Don't know why your battery is deceased but I found out running one completely down won't necessarily kill it. Maybe I was just lucky.....
 
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I have 2 PC 680s, the first one was great for 6 months or so, I did run it dead once, after the 6 months it started having trouble cranking, the prop would stop or almost stop at or near TDC on the first or second blade and voltage would drop into the 9v range during cranking. I replaced it with a new 680 that then worked fine for the first 6 months or so and I never ran it dead but now it’s doing the same thing as the old one.

My engine is IO-360-A1A with the standard 8.7 compression ratio and B&C starter, is this too much engine for this battery or do you all think getting the Odyssey charger will bring these batteries back to life?

Currently I have tried not using a maintenance charger between flights and I have also tried using a Battery Tender between flights, not much difference.
 
Possibly hit the battery with too much initially from the Sears charger - that might have caused venting - with the sealed battery you can't replace the electrolyte. Probably time for the new battery.

This will be a real PITA if you're stuck somewhere and want to get home - with a fast charge or a jump start, your alternator may push too hard on the battery with the same longer-term result.

With the AGM batteries, try using another battery (same voltage, in parallel) with a trickle charger (in the neighborhood of 750 ma) - after a few hours, you should be able to disconnect the second battery and the trickle charger will eventually finish the job off.

The battery comes back to life and will chug along for years (don't ask how I know).

Dan
 
PC680 is plenty for your engine

Russ,
I had almost the exact scenario that you stated except it was with a Skytech starter. After a while the PC680 wasn't turning the engine over very well. I troubleshot and sent my starter back and they actually put on a new motor under warranty. The problem appeared again with a new PC 680 after a few months. I talked to Skytech at Sun & Fun this year and they said the low voltage is a problem in the starter circuit and I should check the starter wiring, ground and the starter contactor. I'm painting my plane now, but it is on a punch list of things to do when I re-assemble the plane. As far as the PC680being strong enough for your engine it has plenty of power. I overhauled an IO540 a couple of years ago that uses a PC680 and it spins the motor very quickly.
 
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