DA40 replacement battery

[neongoby]

Went to my plane on Thursday, and the battery was flat. Local shop sent over a battery cart, and the plane jumped started without problem. Had to run the engine at higher rmp for a couple of minutes before, the G1000 came alive. Flew for a couple of hours. Friday afternoon check on the battery and it is flat again. Am trickle charging it now and see if it is truly dead.
My plane is 2007, I think the battery might be coming to the end. Looking around for replacement battery. Currently installed battery is a Concorde CB24-11M ($440 from AircraftSpruce). Looked and couldn't find any Diamond aircraft listed on any of the battery applications list.
What other battery can be installed, and where can I find the list?

[Steve]

The Concorde RG24-11M is approved for the DA40. Weighs 1.5 pounds less than the CB24, and slightly more energy.

Steve

[Rick]

I have always used the Concord RG24-15M in our ships. It is 3 lbs heavier than the -11M, but more powerful (13.6aH vs. 11aH). It is also the battery that came with all 3 of the DA40's I've flown.

[Steve]

Rick:

The -15M is standard on the newer DA40s. I'm not sure it is approved for older ones like mine (I believe it is also larger, so it will not fit in the battery tray of the older Stars).

Steve

[Rick]

Rick:

The -15M is standard on the newer DA40s. I'm not sure it is approved for older ones like mine (I believe it is also larger, so it will not fit in the battery tray of the older Stars).

Steve

Not sure about the approvals, either. Dimentionally, they are exactly the same (according to the drawings at AircraftSpruce, anyway). Our 2004 Star had one when we bought it, but that is the oldest one I am familiar with. Diamond should have a list of approved batteries, but I couldn't find it easily this morning...

[neongoby]

Followup on my initial posting. Took the battery out and trickle charged it overnight, and all seems well now.

I must have bumped the battery switch as I was exiting my plane, and that caused the battery to drain. However, 2 hours of flight after the jump start did not recharge the battery.

[Rick]

Followup on my initial posting. Took the battery out and trickle charged it overnight, and all seems well now.

I must have bumped the battery switch as I was exiting my plane, and that caused the battery to drain. However, 2 hours of flight after the jump start did not recharge the battery.

Hmmmm... might want to have that alternator tested - something's not right.

[Gary]

Followup on my initial posting. Took the battery out and trickle charged it overnight, and all seems well now.

I must have bumped the battery switch as I was exiting my plane, and that caused the battery to drain. However, 2 hours of flight after the jump start did not recharge the battery.

Hmmmm... might want to have that alternator tested - something's not right.

I agree. After 2 hours the battery might not be fully charged but there should be plenty of juice. It might be worth pulling and testing the alternator and at least replacing the brushes. Bad brushes may not show up on the test stand and I don't think it costs very much to replace them. My mechanic replaced the brushes on my old alternator but I decided to replace it anyway and now have it as a spare.

[Charles]

Can someone confirm whether the -15M is approved on all DA40s? My mechanic installed one in mine about a month ago and it hadn't occurred to me that he might recommend something that's not certified. I don't see any Diamond aircraft listed on the manufacturer's web site: http://www.concordebattery.com/otherpdf/finalfaapma.pdf

[Rick]

Can someone confirm whether the -15M is approved on all DA40s? My mechanic installed one in mine about a month ago and it hadn't occurred to me that he might recommend something that's not certified. I don't see any Diamond aircraft listed on the manufacturer's web site: http://www.concordebattery.com/otherpdf/finalfaapma.pdf

So I thought this was going to be an easy answer... But after coming up empty everywhere I looked, I finally had to call Concorde Tech Support. They told me that Diamond supplies their RG24-15M as the standard OEM battery, but Diamond refuses to release the PMA to Concorde. Therefore, Concorde cannot show any Diamond aircraft in their list of STC or PMA approved aircraft on their website, and technically we must buy our RG24-1xM batteries directly from Diamond (who then buys them from Concorde).

He also said that they are working on a list of "compatible aircraft" that they know the battery will work in (with no reference to the FAA), and they are going to post that on their web site "soon". He also said that Diamond was not the only manufacturer that has put them in this position. Interesting...