Odyssey Battery question

Last Saturday the my plane wouldn't start after pulling it out of the hanger and preflighting. The prop moved about six inches and stopped when the engine hit the first compression stroke. A couple of more trys with each giving a less impressive result than the first so I quit trying. The battery guage on my panel showed about 11 volts after the several attempts at a start.

Off came the top cowl and on with the charger. I did find the positive cable slightly loose at the battery and tightened it hoping that this was my problem and somehow kept the battery charging correctly on a night flight a few days prior. After getting it started a while later the alternator output was around 13.5 or just slightly higher and everything looked good so I went for a ride lasting a couple of hours. Hopefully this weekend the dumb thing will start or a new battery will be on its way.

Question... How do these Odyssey batteries do in cold weather? It was around 40f degrees in the hanger the morning that the plane wouldn't start. (That's cold here anyway) This is also the 2nd battery in 2 1/2 years.
What kind of life are you getting out of yours?

Thanks,

It's not the Battery...

its your charging system, minimum charging voltage should be 14.2 - 14.5 anything less than that and the battery will never get fully charged. Be sure to check charging voltage with a known good digital voltmeter as typical panel analog gauges can be off quite a bit. These are great batteries and they will last for years if taken care of, for a battery that means correctly charged and kept fully charged all the time and not run dead. I replace mine every 2 years though just to be safe. If I was to ever completely kill it I'd replace it, I run dual lightspeed ignition so electrical system health is very important to me!

I'm well into my second Odyssey battery. From my experience and others, they'll last 2-3 years. Some maybe more.

Cold makes all (electrochemical) batteries less effective.

Does sound just slightly low on the charging voltage. But mine runs in that range occasionally depending on the system load and state of recharge after start.

Try putting a trickle charger on it between flights. If it starts nicely with the trickle charger, then you can be a little more certain it's not a completely failed battery (i.e., more probability of the charging system).

You sure there's no small drain on the battery between flights? Clock, etc.

Thanks

Thanks Walt and Bryan. I'll check to see if there is 14v+ during charge this weekend and go from there. As far as a drain, pretty sure there is no draw on the battery with the master off. I'll pull the lead off the battery though and check it with an ammeter.

Best,

Radios

Hi Bryan,
Our Oddysey went dead overnight after we installed the VAL radio. An amp draw check showed 200 milliamps so I called the factory. They said, "Yup, 200 mill is correct". I couldn't believe it so I cut the memory wire to stop the draw and now the radio always reverts to 121.7 after shutdown but it's no biggie.

Regards,

Bryan Wood said:

Thanks Walt and Bryan. I'll check to see if there is 14v+ during charge this weekend and go from there. As far as a drain, pretty sure there is no draw on the battery with the master off. I'll pull the lead off the battery though and check it with an ammeter.

Best,

Click to expand...

Just a little more infor on the Odyssey.

It is an AGM battery (absorption glass mat) and must be charged with a charger designed to that technology. A regular old lead acid charger will destroy the Odyssey quick.

The difference is charging voltage. The AGM requires 14.4-14.7 volts for quick charge and 13.6-13.8 volts for standby service. This information is from the Odyssey web site. Battery condition is easily checked with a volt meter. 12.8 volts is 100% full and it drops off from there. There is a chart with this information and as I recall, if your battery voltage was 11, it was all but totally dead. You could have a short or perisite drain in the electric system. These batteries will maintain a charge level for quite some time on the bench.

Another factor affecting life span is heat. I moved my batteries out of the engine compartment to the cabin floor for this reason (and CG purposes). Odyssey does make a metal jacket version for high heat areas. This is not the battery Vans sells.

I changed both batteries (the Subby has 2) this year after 4 years of service. They were both still working fine but I thought, why push it. The batteries were sold cheap to another builder who using them for test work. It is not uncommon for an Odyssey to go 7 years in other applications.

They are good batteries.

dd

Battery charging

I too have found that the Odyssey is nearly dead at 11V. It does start our O-320 REALLY well at anything over 11.4 or so. I have tried it down to 30 degrees and don't plan on anything below that without engine heating, so I think I'm in good shape. Since we were using so much power during testing (flaps, trim, radios, etc.) without running the engine, we were recharging often. I modified a standard female plug and wired it in under the oil check door and modified a male plug and attached it to our charger. Sure beats pulling the top of the cowl!

Bob Kelly

You may want to contact Odysey. I believe 11 volts is the magic number where the chemistry of the battery starts to change. I think it's fixable but I forget the procedure. Maybe I'm just not remembering this right. Anybody?

jcoloccia said:

You may want to contact Odysey. I believe 11 volts is the magic number where the chemistry of the battery starts to change. I think it's fixable but I forget the procedure. Maybe I'm just not remembering this right. Anybody?

Click to expand...

If the Odyssey is flat dead, it will take a charge in reverse polarity. A friend left the master switch on and in his haste to connect a charger under the IP, hooked the leads up reversed. The battery took a full charge and the next day when he turned the master on, blue smoke appeared instantly everywhere. Some of the electric system was fried but fortunately, none of the avionics.

When my machine was wrecked, both batteries discharged to about 4 volts due air frame damage and the resulting shorts. I recharged them, let them sit on the bench for some 6 months while rebuilding and used them another 2 years. As I said earlier, a friend is using them as he builds his airplane. They still hold a charge and perform OK. Tough little batteries.

dd

Checked the battery today

It's been a week now since using the plane and I checked it out today to see how the battery voltage held up. The hanger was cold just like last week, only this time the battery was reading 12.6. I guess the slightly loose positive cable at the battery was causing a charging issue? Also checked the voltage with the engine running and just like you folks said it was over 14volts so the system looks fine. Also no draw when everything is off.

This has me thinking though about putting some kind of jack that you can get to from the oil door on the cowl like others have done. If this happened away from home it would have been a pain in the neck.

Thanks again for your help and Merry Christmas to all of my fellow RVers.

Good info

Glad all is well, Walt is right on the Volts.

>15 volts is too much and damage will occure
>14.2-15 volts for full charge
>14.3-14.6 volts Nominal charge (ideal)
>14.2 volts, less than, battery never charges fully
>13.6 volts for trickle or float charge
>12.6 volts standard voltage

Approx charge state
12.84 volt = 100%
12.50 volt = 75%
12.18 volt = 50%
11.88 volt = 25%

At 11 volts your battery was beyond dead (if that is possible).

Odyssey's are rated down to -40C(-40F)

Odyssey battery and charger

I bought my Odyssey battery in August 2004 and got the trickle charger for it that will put out 2 amperes (RED LED) when the battery is not at full charge, then cuts back to trickle rate (green LED) when the battery is topped off. The Hobbs meter has 212.5 hours on it as of today.

I have several items in my airplane that have memory circuits. That is why I have a cigarette lighter power socket inside the cabin where I can plug in the charger when the airplane sits in the hangar. I have left the master switch turned on twice. The battery recoverd both times. The first time was during final assembly at the airport. The battery voltage was VERY low that time and it recovered in two days. The second time was just a week ago, and it recovered in 1 day.

By the way, that power socket also accepts a solar panel power charger when I go to Oshkosh each year. I put in the socket to allow me to run my computer or other items when flying. The other items include a 120VAC power inverter to operate my camcorder through its original universal charger, and a remote video camera via its universal charger. That combination of video equipment lets me use external audio from my GMA340 to the camcorder when flying. Any audio I can hear in my head phones also goes to the digital camcorder while the dash-mounted surveillance video camera sees the action outside. I got great videos going into and out of Oshkosh this year.

I also have a car stereo CD/Tape player in the airplane. The stereo music from it goes on the camcorder in full high-fidelity. With real-time narrative in flight, and musical sound tracks, it makes a completed video during the flight. I use the ICS mute inhibit option on the GMA 340 that allows me to talk over the music, not mute it. Receiving a radio transmission will mute the music.

Jerry K. Thorne
East Ridge, TN
RV-9A N2PZ
www.n2prise.org