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Requesting input on batt replacement and Sporty's batt tender

Rocinante

Member
In my 'new to me' RV 6 (which I love a little more every time I fly it), I have an Odyssey PC 680 batt installed in 2017, last owner (who, by my lights, seems to have taken very good care of it) placed this batt, and never used a tender.

The manufacturer gives us the wide range of '3-10 yrs' life expectancy for the batt. Currently, the batt performs well for me, and turns the engine over very nicely on each start.

Beyond waiting for the batt's performance to show signs of decrement, the easy answer is just to go ahead and replace it now (which, of course, is cheap insurance), but I kind of hate to replace a normally functioning batt prematurely (I wrestle with being a bit too parsimonious).

1. what kind of longevity are people getting from this batt? Beyond outright failure, what are the usual events/symptoms that trigger getting a replacement?

2. I have always used batt tenders on my motorcycles w/good results. Has any one used the tender that Sporty's offers? Any comments, reviews on that, or any other tenders?
 
You’re going to get a variety of opinions, yes and no, on using a tender. But if you do decide ‘yes’, note the Odyssey is a sealed glass mat design, requiring, for best results, slightly different voltages than a wetcell lead acid battery.
 
First off, congrats on the "new" 6 :D

As far as I know, do not use a tender.

If you run the battery down, charge it and then remove the charger.

Do some searching here, lots of info.
 
PC680 on my -6a going strong after six years, all parameters normal. I thought at one point it was going to be a short lived one when the blades would not turn smartly during start, but that turned out to be the ancient starter solenoid.

If you do get a charger, make sure it is one blessed by Odyssey for your particular battery.
 
I’ve replaced PC680’s three times over the years, each of them after about 7 years when the engine start seemed to be getting a little slower than normal. I’ve almost never used a battery tender. The “old” batteries I removed are still on my work bench providing 12v power when I need it to test something. I charge these ones about every six months.
 
Your alternator will charge your battery during normal use. There is no reason to use a battery tender unless you are going long periods of time between flights (months), you have powered some avionics up without the engine running, or your electrical system is faulty and has some sort of constant drain on it even when everything is shut down.
 
Thanks to all,
All points well taken.

I also probably should have mentioned that part of my concern, with regard to the potential use of a battery tender, was in the setting of knowing that I would probably have longer stretches, possibly months, between flights during the winter here in Indy.

And my thanks and apologies to the moderators, for moving this question; I should’ve thought to put it in here in the first place.
 
Battery Requirements and Testing

I suggest considering the importance of battery life after an alternator fails in flight.
- Will the engine stop if the alternator dies and the battery is too weak to get you to the next airport or do you have magnetos or something similar?
- Do you fly IFR and need to make sure the navigation and flight instruments keep working?

You could consider completing a load test annually. I couldn't find it, but I remember reading information by Bob Nuckolls about battery tenders and battery load testing. I bought his (USB Key) book and recommend it. He also has articles located at:
http://www.aeroelectric.com/articles.html

Regards,
Brad
 
In my 'new to me' RV 6 (which I love a little more every time I fly it), I have an Odyssey PC 680 batt installed in 2017, last owner (who, by my lights, seems to have taken very good care of it) placed this batt, and never used a tender.

The manufacturer gives us the wide range of '3-10 yrs' life expectancy for the batt. Currently, the batt performs well for me, and turns the engine over very nicely on each start.

Beyond waiting for the batt's performance to show signs of decrement, the easy answer is just to go ahead and replace it now (which, of course, is cheap insurance), but I kind of hate to replace a normally functioning batt prematurely (I wrestle with being a bit too parsimonious).

1. what kind of longevity are people getting from this batt? Beyond outright failure, what are the usual events/symptoms that trigger getting a replacement?

2. I have always used batt tenders on my motorcycles w/good results. Has any one used the tender that Sporty's offers? Any comments, reviews on that, or any other tenders?

Here in Minnesota, we have distinct and occasionally brutal seasons. I have a small fleet of seasonal rolling stock and in any given season at any given time I have a number of vehicles on float chargers...boats, motorcycles, cars, mowers etc in the winter and snowmobiles, snowblowers and etc in the summer. Tractors and airplanes that aren't used every day are plugged in year-round when not in use. I've been doing this for decades...since float chargers were invented. My knowledge of lead-acid battery chemistry and my battery-replacement frequency has been such that I am utterly convinced of the value of float-charging batteries that aren't in use. Sulfation is the main killer of batteries, and sulfation begins when the battery has any level of discharge.

My RV-9A has two PC-680s in parallel for onboard power...one for power and the other on a separate buss for backup. I plug the airplane into an Odyssey OBC-6A float charger before shutting the hangar door for the evening. For avionics doodling, I have an Amazon switching power supply that I can plug the plane into so that the avionics don't have to filter the pulsing de-sulfation current.

Bottom line IMHO...no downside to keeping the battery charged to the max 24/7, and a huge potential upside.
 
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Check Odyssey’s web site for a go, no/go test.

Odyssey has a detailed test you can perform to tell the health of your battery.
The info sheet is at the hangar but I remember entailed removing the battery connections so there is absolutely no load on it, bringing it to a full charge and then waiting 8 hours and checking the voltage with a digital multimeter. Anything over 12.4 volts is considered a serviceable battery. Any reading under 12.4 and the battery is toast and needs to be replaced.
 
In my 'new to me' RV 6 (which I love a little more every time I fly it), I have an Odyssey PC 680 batt installed in 2017, last owner (who, by my lights, seems to have taken very good care of it) placed this batt, and never used a tender.

The manufacturer gives us the wide range of '3-10 yrs' life expectancy for the batt. Currently, the batt performs well for me, and turns the engine over very nicely on each start.

Beyond waiting for the batt's performance to show signs of decrement, the easy answer is just to go ahead and replace it now (which, of course, is cheap insurance), but I kind of hate to replace a normally functioning batt prematurely (I wrestle with being a bit too parsimonious).

1. what kind of longevity are people getting from this batt? Beyond outright failure, what are the usual events/symptoms that trigger getting a replacement?

2. I have always used batt tenders on my motorcycles w/good results. Has any one used the tender that Sporty's offers? Any comments, reviews on that, or any other tenders?

If it ain't broke....don't fix it...... ;)

My AGM RV batteries over the past nearly 20years (mix of Odyssey and "off-brand") usually last several years before a noticable decline in starter performance is noticed. Mine have retired gracefully giving plenty of warning.
 
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A fresh Odyssey

Since it appears we have a lot of eyes on this subject I was wondering if anyone knew of a source for the freshest PC 680’s.
A tour of a battery plant years ago taught me that a battery’s actual life cycle started at the date of manufacture. I’m sure a lot of the batteries sit on the shelf of some vendors for a long time before getting sold. Anyone know who has the highest sales figures for the 680 ? Bought a ELT battery a few years ago and it already had 4 months off it’s life span.
 
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