agreed, I'll be using Aerolithium for the same reasons except for the ' certified ' part which I dont care about and they are a little less costly.
agreed, I'll be using Aerolithium for the same reasons except for the ' certified ' part which I dont care about and they are a little less costly.
PC-680. Long shelf life and if needed, almost any battery charger will work. Readily available.
See my build log at:http://www.mykitlog.com/lowandslow/
As Jim suggested above, there’s more to choosing a battery than its cranking ability and price tag. Consider a few questions:
- Are you using an engine with one alternator, or two?
- Is your engine self-sustaining, or does it require electricity to run?
- How do you plan to use the airplane (VFR or IFR, back-country, cross country or local)?
- What is your ship’s running airframe electrical load?
- What are you willing to turn off to shed electrical load if all power generators fail?
- How much battery-only endurance do you want to achieve?
- How hyper-focused are you on minimizing empty weight?
Your battery capacity and chemistry preferences will be different depending on how you answer those questions.
For a Rotax engine, check the electrical section (chapter 24) of the engine installation manual. For all of the 900-series engines Rotax recommends a battery with at least 16Ah capacity and 350CCA, but the capacity will obviously be more critical for an electrically dependent engine like the 912iS or 915iS, for which a dead battery = no thrust. The same consideration would apply to any automotive conversion with high pressure fuel pumps, electronic ignition and an ECU.
As an example, I’m using a 912iS in a plane that will be used for day/night VFR and some back-country flying. I plan to use an EarthX ETX-900 (15.6Ah, 400CCA). My plane will be configured to aggressively load shed if I lose both alternators and have to run the engine on battery only. The entire Dynon suite, transponder, ADS-B and most lights will be shut off. I’ll finish the flight using a standby instrument (combined altimeter, airspeed and VSI), comm radio, landing and cabin lights (only as needed) and pitch trim. All of that adds up to a few hundred miiliamps of average load. Finally, I’ll test the battery at least annually to verify its capacity.
Eric Page
Building: Kitfox 5 Safari | Rotax 912iS | Dynon HDX
Member: EAA Lifetime, AOPA, ALPA
ATP: AMEL | Comm: ASEL, Glider | ATCS: CTO
Map of Landings
I respect everyone's own decision but want to put in my reasoning for going with a powersport lithium battery rather than EarthX. Obviously the big one is cost. I spent $160 from Amazon for the NOCO battery I chose versus $380 for the EarthX. The EarthX is certainly a proven option, but having used lithium powersport batteries in motorcycles for a few years I had some experience with them. Eric brough up some points about the EarthX that I compared to what you get with a powersport lithium battery below. Everyone has to weigh the pros and cons of every selection on building an airplane. For me the cost, the fact that the Kitfox is a VFR airplane, and my previous experience led me to save the $200+ and I don't regret it. For others the differences may be such that you feel more comfortable with the EarthX and that is fine. Just giving my view.
- Fully built-in, proven cell balancing and safety circuitry.(All lithium batteries require some kind of BMS. At least the NOCO I have and the antigravity do have BMS with over-discharge, over-charge, thermal protection and cell balancing.)
- Now certified for use in certified aircraft.(EarthX has the corner on this but homebuilts don't need certified products.)
- Lithium-Iron technology-safer than Lithium-Poly. (Virtually all powersport batteries are Lithium iron phosphate, not Lithium polymer so I don't see how this is a factor)
- 10# weight savings compared to AGM.(You get this with powersport lithium batteries too)
- Great cranking power. (Same with powersport lithium batteries)
- No need for trickle charger. (Haven't needed one on my 582 powered Kitfox with powersport lithium battery either and the 582 has a weak charging system compared to even a 912UL.)
- Panel mounted fault light. (The powersport batteries don't have this, but then again a standard battery doesn't either. For a vfr airplane I don't see this as a huge deal.)
John Brannen
Morris, IL
Sonerai IIL (Single Seat)
Kitfox 3/4 1050 - Rotax 582 (Back Flying and sold)
Kitfox IV 1050 - Rotax 582 (sold)
Kitfox IV 1200 Speedster - Rotax 912 UL (rebuilt and now flying)
Piper Twin Comanche (Sold)
Glasair 1 FT (Waiting to start)