Want Battery Recommendation for Rotax 503

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sptomh

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Upon rereading the article it seems a little ambiguous. I now see that even the provision 8 has a frequency that is lower than recommended. I know that lithium’s are used in a lot of motorcyles which have similar charging systems without problems. The charging system in the 503 is made by Ducati if I’m not mistaken.
 

Mac Hodges

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Upon rereading the article it seems a little ambiguous. I now see that even the provision 8 has a frequency that is lower than recommended. I know that lithium’s are used in a lot of motorcyles which have similar charging systems without problems. The charging system in the 503 is made by Ducati if I’m not mistaken.
As I stated earlier, I have a couple of Lithium LiFePO4 batteries in two Rotax 503 powered aircraft. The 503s have the Ducati ignition and charging system and I have flown both airplanes a lot over the last 3 years and have had no issues at all. I just get in the plane, crank, and fly. The battery is always fully charged and ready to go. I have a gps, IPad, strobes, and nav lights.
 

challenger_II

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Rather old thread, but I will jump in with what I know.
When using a LiFe (such as the Battery Tender unit) on a Prov.*8 Rotax 503, the voltage regulator is important. After doing a large amount of research, and visiting with the folks at BT, the optimum voltage regulator to use is the Key West unit, as used with the Kuntzleman Hot Box. As compared to the two regulators normally used with 447's, and 503's, it gives a smoother waveform output, and doesn't irritate the LiFe battery.

I have used the Battery Tender 240ca on a 503 and it starts WAY easier than with an 18AH gel battery.
 

Cass256

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Rather old thread, but I will jump in with what I know.
When using a LiFe (such as the Battery Tender unit) on a Prov.*8 Rotax 503, the voltage regulator is important. After doing a large amount of research, and visiting with the folks at BT, the optimum voltage regulator to use is the Key West unit, as used with the Kuntzleman Hot Box. As compared to the two regulators normally used with 447's, and 503's, it gives a smoother waveform output, and doesn't irritate the LiFe battery.

I have used the Battery Tender 240ca on a 503 and it starts WAY easier than with an 18AH gel battery.
Thanks for the input, just curious if there's any problems using CBs instead of a fuse box?
 

Rhino

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Although it may have been written a while ago, Bob Nuckolls seemed to be a great fan of recombinant gas batteries in The Aeroelectric Connection. Although often called gel-cells, Bob says they technically are not. I'm not really all that concerned with the engineering and chemical aspects though. I just want the best battery with the smallest weight and lowest maintenance (don't we all?). Anyway, it looks to me like the RG battery is just another version of sealed lead acid, but someone correct me if I'm wrong on that point. Being a former avionics troop in the Air Force, I'm planning on lots of whizz bang gizmos in my cockpit, to include radios in the fire/police bands for some of the disaster response stuff I do. Obviously I need to crank the prop, but none of that extraneous stuff would be needed if I lost my alternator, which is notoriously underpowered on the Jabiru by the way. I'm planning a built-in backup battery for my EFIS, and won't need a whole lot other than that in an emergency (no night flying or IFR for sport pilots). From what I've read here and somplaces elsewhere, I'd get along pretty good with a lightweight LifPO, without the extra weight of an RG (not greatly worried about cost). Am I on the right track?

Sorry for resurrecting an older thread, but it seemed to fit my question.
 

rv7charlie

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Well, my philosophy for me is what I wrote in post#7.

If you really want to spend the money to save weight, do your homework researching *actual* amp-hour (total energy) capacity of the battery you're considering. Those little 2 lb fist sized devices that will start an IO540 will last about 5 minutes after the alternator fails (very little total energy, or 'gas in the tank'). Lithium tech variations can dump a lot more *power* (starting duty) but the actual AH rating is what tells you how long they'll last after an alternator failure.

Actual Gell Cells are a different animal from today's SLA/AGM/RG/etc etc (all the same thing). Gell Cells are actually kinda hard to find these days, and that's a good thing; they have some...unpleasant... characteristics.

If you don't already have the AEC book and monitor the AeroElectric list, I'd strongly advise hanging out there for quality answers.
Job One is determining total electrical load, and Job Two is determining minimum required electrical load to stay in the air. If the Jabiru alternator is as under-endowed as you say, you may have to rethink the number of gadgets, or add an alternator to handle your total load, adding in some excess capacity to recharge the battery. Your minimum required load to continue flight (plus realistic margin) times flight duration you expect to need after alternator failure determines battery AH (total energy) size needed. Derating is essential; batteries lose capacity as they age.

If your mission is flying circuits around the airport, obviously you can relax the requirements a bit.
 

Victor Bravo

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I have a 503 powered Ridge Runner, sort of a single seat Avid flyer. I'm guessing pretty low current drain, I have a Becker low-ampere European glider COM radio and an old King transponder (which I have to keep, because I'm based at a city municipal airport and will need the wingtip ADS-B gizmo).

Got no "full stack" IFR crap, no audio panel, no hot leading edge de-ice, and I took the big Whelen strobe box and light out.

The only big deal is that I may be out in the desert somewhere when I really want the thing to start and get me home. Waaaay too old, fat, spoiled, and fussy to want to camp out at night with the rattlesnakes.

So that's what I want to figure out... can I use one of the modern miracle Li-Fe 2 pound batteries, or should I eat the extra few pounds and get a 10 or 12 amp Odyssey?
 
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Rhino

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Thanks, rv7charlie. I do something similar to what you do, find out what's spec'd, and then get something a little higher powered. The Jabiru comes with a 20 amp alternator that many builders say isn't good enough. There's a higher powered Rotec battery available for it, but there are several reports of reliability issues with it. I'll get a heavier battery if that's what it takes. I just didn't want to add that weight if something lighter could do the job for me. I already have Bob's book, and I've checked out the Matronics list a couple of times, but haven't dug too deeply. I just didn't want to add the weight of something lighter could do the job, and some comments about LifePO were making me a little hopeful.
 

aerolithium

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ok, my 2 cents;
most any battery is gonna start your engine.
So, How much Ah / reserve capacity do you want to buy ?
Is the up front cost a major factor or is cost over the life of the battery ?
lastly, do you care if the lithium battery has a BMS or not ?
Many LiBatts, like the Ballistic / Aerovoltz and Twin power, Deltran, Noco, etc., dont have a BMS. ( some may have a simple PCB and call it a BMS )...The BMS adds complexity and weight and cost.
Most lithiums now are chinese batteries with a private label slapped on, they're flooding the market and the prices are going ridiculously low.
Its a little like picking which flavor ice cream ...
 

ToddK

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Get a Shorai Lithium Iron and a SkyRC imax B6AC charger. Done. Every couple of months hook up the B6 and do a balance charge. You can use the Aerovoltz video instructions to set up the charger. Its very easy.
 
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