Rivethead

Well Known Member
I'm trying to choose whether to go with the Odyssey battery or go with the Concord battery. I have the parts to do both and each looks to be about the same amount of hassle factor to install. Weight is an issue as it should be. On the other hand capacity has it's benefits. One of the questions is, is there a large difference in capacity? I'm wanting to get opinions from both sides of this fence so please step up and have your say.
 
Location

The Odessy, according to Van's is for the right side, Condord for the left. I find the Concord makes it impossible to duct the exit air from the oil cooler.
 
My Odyssey PC680 is over three years old and is doing just fine cranking my 0-360. If you are running a fixed pitch prop. The extra weight of the Concorde will help balance problems. Otherwise, go Odyssey.

Roberta
 
Capacities...

Rivethead said:
I'm trying to choose whether to go with the Odyssey battery or go with the Concord battery. I have the parts to do both and each looks to be about the same amount of hassle factor to install. Weight is an issue as it should be. On the other hand capacity has it's benefits. One of the questions is, is there a large difference in capacity? I'm wanting to get opinions from both sides of this fence so please step up and have your say.

Capacity (Ampere-Hours) is approximately 2 to1 difference, depending on the exact measuring conditions.

A constant 25 amp drain is good for 25 minutes on the PC680, and about 58 minutes on the Concorde RG 25 XC batteries. Makes sense since there is almost a 2 to 1 weight difference too... (23.5 lbs. to 14.5 lbs.)

If you have an all-electric RV with only one alternator and fly IFR in areas of the US that need pitot heat this might make a difference.... :)

gil in Tucson
 
Odyssey PC 925

Is perhaps a better battery to compare to the Concorde. I changed from the 680 to the 925 because the 680 had issues turning over the light wood prop. The 925 works well.
 
Odessey batteries...

ronlee said:
Is perhaps a better battery to compare to the Concorde. I changed from the 680 to the 925 because the 680 had issues turning over the light wood prop. The 925 works well.
That's definitely true... however Van's firewall mount kit is for the PC 680. A lot of RVs are starting with this battery.... :)

If you use the alternate "standard" aircraft battery mount, then the PC 925 and RG 25 XC are very similar in weight (PC 925 is 24 lbs) and similar in 25 amp capacity (50 minutes for the PC 925).

The prices even seem to be similar... I guess you buy them by the pound :)

gil in Tucson
 
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Happy w/680

True, I am flying VFR, but I can't see much need for more amp/hr. Even when I convert to IFR I think that will hold true. I have one E-mag and one magneto. With all but minimum equipment turned off, as a test I have flown for over 45 min and still had enough battery for an engine start. With battery backup for the gps, Dynon and radio (the backup hand held,) I can see the 680 getting me out of even pretty tough situations. Pitot heat would change that a lot, I'm sure, but if the alternator fails, I'm outa the sky ASAP. Remember that the RV community is there to help, once you get on the ground. Stay away from cheap alternators to cut that risk as much as possible. Also, the 680 will start my 320 at any temperature that doesn't require heating the engine and probably some that do. For me, it was a good choice. YMMV.

Bob Kelly
 
No question for me - Odyssey. On batt no. 2 after 6-7 yrs. Concorde used initially.

Saving the weight is golden, and I don't need the extra energy capacity of a Concorde. The Odyssey starts my plane just fine 99% of the time. Those where it didn't were when it was exceptionally cold and I hadn't run the engine (charged the battery) in a month or so.