What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Odyssey Battery - PC-680 woes

WingnutWick

Well Known Member
So I've had the RV-8 for 7 years and think I am on my 5th Odyssey PC680 now. From my experience it seems that as the central valley summer heat transitions towards winter, almost without fail the battery....fails. It'll start with a couple dicey starts and then fail to consummate a full start shortly thereafter.

Replacing batteries this often seems to be excessive and therefore I deduce that I am doing something wrong. I do not keep my battery on a tender and sometimes it will go a few weeks without flying. Outside of that, I am unsure what would cause this. Unless, for some reason...replacing batteries all the time in airplanes is the norm??

Looking forward to the insight out there!

Cheers

Charles
 
My P-680 equipped -6A lives in San Martin, one set of hills west of Lemore. Not as hot as the CA central valley, but not that much cooler in the summer. My first P-680 lasted about 5 1/2 years. The second one is still in service, about 2 years.

I'm with gasman......is there ANY drain on the battery with everything shut off? A USB power outlet on the always hot buss? A clock?
 
Charging specs

The spec for the PC680 states:

Charge at 14.4-14.8 Volts
Recharge when below 12.6V
Expected battery life 400 cycles at 80% discharge

How does your battery usage and care compare to the spec, especially charging voltage?
 
My first one had a short life, with a generic battery minder. My second one is doing very well with an Odyssey-approved one that I only put on if it has been more than a week or two without operation.
 
I have a couple of PC680s in parallel. Second one is a backup on the second master switch. When the plane isn't sitting, I leave them connected 24/7 to an Odyssey battery charger OBC6A.

IMHO, the major killer of these AGM lead/acid batteries is sulfation, and the major cause of sulfation is undercharging, not charging, or storing discharged. I'm confident that keeping the battery on a float charger is the best preventative measure. I was always kind of suspicious of chargers that touted "de-sulfation" as part of their feature set, but the more I read about them these days, the more I'm inclined to believe that they at least help to prevent sulfation. Not as clear as to the extent that they might actually reverse extensive sulfation and rescue a dead battery.
 
IMHO, the major killer of these AGM lead/acid batteries is sulfation, and the major cause of sulfation is undercharging, not charging, or storing discharged. I'm confident that keeping the battery on a float charger is the best preventative measure. I was always kind of suspicious of chargers that touted "de-sulfation" as part of their feature set, but the more I read about them these days, the more I'm inclined to believe that they at least help to prevent sulfation. Not as clear as to the extent that they might actually reverse extensive sulfation and rescue a dead battery.

I agree with MacCool.

Using a state-of-the-art trickle charger is the only way to go. Aside from the de-sulfation concerns -which I agree are very real - the battery is always "ready to go" for that first engine start. And, your on-board charging system doesn't suddenly need to go to maximum output to recharge a partially depleted battery. A smart Battery Tender makes sense to me in so many ways and they are cheaper than the price of a new battery.
 
One other thing...

You really need a volt / amp meter display so you can monitor it and pick up trends year round. That way you'll always know the health of your charging / storage system and won't instead be alerted to impending trouble by a now slow-cranking engine.
 
Back
Top