lithium-ion batteries

Tom-D

Tom-D

Taxi to Parking
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Tom-D
Tell me what we need to know about lithium-ion batteries, will we see them being use in GA aircraft?

More questions to follow when I understand enough to ask them.
 
What are your principal concerns? Li ion batteries have much higher energy densities that lead acid batteries. Depending on type, voltages per cell is 3-4 V. Cathode materials are mixed metal compounds with lithium and typically cobalt, iron, or manganese. The electrolyte for most Li ion batteries are liquid, organic, and flammable, which is a safety concern if batteries are physically damaged or experience high rates of discharge. Charging and discharging circuits must protect from overcharging or overdischarging to prevent irreversible damage. Self discharge rates can be high, much like NiMH batteries, although this problem has improved over time.

The Battery University web site is an excellent resource for understanding battery types. Probably more than you want to know.
 
I have one in my motorcycle....................Super great in the summer...............not so hot in the winter. But then, I don't ride much in winter!

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Weight savings is the big positive. Cost and another point of failure (the controller/regulator hardware) are negative IMO. I'm a fan of Lithiums and own an electric car but I'm not yet ready to swap out an AGM for something with the potential to be less relaible.
 
Lithium-Iron Phosphate (LiFePo4) batteries are quite a bit more stable than the Li-ion batteries that got such a bad rep a few years ago. The EarthX batteries are flying in quite a few airplanes. As long as you follow manufacturers instructions, they work pretty well and weigh a lot less than traditional lead-acid and AGM batteries.
 
lol, this is an old thread, an old story/video but it made me perk up when I first was wondering about putting one in.
Certainly the situation was unusual and the technology is probably much better now. I went with Odyssey (lead) but might do the modern Lithium later.
 
They are expensive. True blue has a new Lithium Ion battery and its pricey. You will need a battery charger with amp control, not a big deal. I believe most of them are all billed a no maintenance battery. As stated above, there will be more things to fail in your charging system.

On the plus side though, charging is fast. Charged a True blue TB17 in 3 minutes at 17 amps.

I can't imagine they will be hugely popular unless Cirrus or another big manufacturer adds them from the factory.
 
One of these days, all these batteries will be replaced by capacitors. There are already trucks, and buses using capacitors for cranking, in lieu of a bank of lead/acid batteries, way less weight. One battery, and a capacitor, instead of 4 batteries in series.
 
In what capacity? You mean instead of the starting battery? To power an electric primary motor? They're likely already present in some avionics and the like.
 
flyingron said:
In what capacity? You mean instead of the starting battery? To power an electric primary motor? They're likely already present in some avionics and the like.
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Instead of the starting battery. Which is typically a bank of 2 or 4 lead/acid batteries in series. The caps used for cranking, and a single conventional battery for running.
 
I have three EarthX ETX900 batteries. One powers my Cub and resides between my feet on the firewall. Great batteries. They work great in the cold, too, once you learn how to use them. Sizing the battery properly to the charging system is important. Ground-based chargers are also important. Use the wrong one and you’ll have problems. That’s not a battery problem, its an operator problem. I bought an OptiMate LiFe specific battery charger. Works great, no hesitation to hook it up and walk away.

The ETX batteries have a fault light in the battery case that flashes codes. They also have a short lead for connecting a panel-mounted indicator light, which I have. My first battery flashed a code so I called EarthX. They said I had a bad cell and sent me a new battery. Excellent customer support! That battery still works fine but not in my airplane.

I know guys are switching firewall mounted Odysseys to the new TSOd EarthX. I’ll do the same if my Odyssey ever craps out. No reason to do it sooner.
 
tsts4 said:
I just installed an EarthX ETX1200 LiFePO4 battery. It's tiny and about a third of the weight of the Odyssey PC925 it replaced. I'm liking it so far. They offer a TSO'd model for standard certified aircraft too: https://earthxbatteries.com/product-category/certified-aircraft
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Yes they have a TSO’d 12V battery and no STCs that provide the procedure and hardware to mount a non standard size battery in the certified aircraft.
 
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Stewartb said:
https://earthxbatteries.com/wp-content/uploads/2019/04/180407-ETX900-TSO-Manual.pdf
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Thanks for posting that, it really documents how economically impossible this installation is for a certified aircraft. First, I have to demonstrate to the FAA the environmental conditions at the mounting location will not exceed battery specs. Then the low voltage warning value, if applicable, has to be raised to 12.6 volts. How does a mechanic do that? It goes on from there.
 
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Quite the contrary. Guys are getting field approvals to put EarthX batteries where they had Odysseys. Use 43.13-2B chapter 10 and field approve the ETX TSOd battery.
 
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