EarthX STC approved!

No thanks, I'll stick with my Odyssey ...
 
I talked to them at osh and they mentioned the stc's being approved. I figured I'd wait until my current battery dies, but now that I see it's 25 pounds lighter :yikes:, in the nose where I need it most, I'm thinking I'm just going to order one. By FAR the cheapest dollars/ useful load gain available.
 
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The ETX-900 in my Cub has been excellent. I’ve had Odysseys in my Cessna for 25 years and they’ve been excellent, too. I’ll be switching to an ETX.
 
3x the price gives you weight savings and….? Tia
 
So $894 for the battery, they say it lasts 6 years. I get about 7 out of the Concorde as it is. Other than the weight savings, I don't see why I would jump ship.
 
I'd consider it if they had 24v. Not much price difference from the Odyssey.
 
If you aren’t interested? Move on. If you’re curiou about how it works? Ask someone who knows. This is a development that many will utilize. No modification suits everyone.
 
So $894 for the battery, they say it lasts 6 years. I get about 7 out of the Concorde as it is. Other than the weight savings, I don't see why I would jump ship.
The lady at the show said that and I must've made a face because she backpedaled and said their experimental batteries (which have been available for a long time) have been seeing about double the life of lead/acid.

Also 1/3 the amp hour capacity.

Could be a BIG factor when flying IFR.
This is a concern. The battery for my plane is more like half. Doing a little research into it, it seems like lithium batteries have a very flat discharge curve, maintaining voltage until they are empty, and doing so consistently even at higher draws. Apparently a 35AH L/A will provide 1 amp for 35 hours, but increase the load to 15A and it's far less than the 2 hours you'd expect, with the voltage dropping off faster as well. Supposedly the EarthX was sized to provide a similar usable reserve to the original L/A. TBH if the choice was between a 5lb 15AH battery and a 10lb 30AH, I'd take the latter. As it is, they show an hour or reserve at 15A, which is about what my plane runs normally. I always assumed I'd get about 30m out of my L/A, so I guess I'm comfortable with that.

I've had a lithium battery in my off-road Sportster for several years. It has surprised me several times when the bike hasn't run for months and the battery is still fully charged. It has outlasted the lead/acid in my big bike 2:1; the next battery that goes in it will be lithium.

One thing I'm not crazy about on the EarthX is the warranty is only two years.
 
Just replaced the battery in my 182P and considered the EarthX.
EarthX $900, 5.4 lbs, 15.6 Ah.
Concord $500, 32 lbs, 33 Ah.
For me the capacity of the battery outweighed the weight savings flying IFR.
I did a capacity test on the Gill 35 I removed. It was 13V 24 hours after charging but down to 16 Ah capacity (23 Ah new). Plane was getting slow to start with the 5 year old battery.
Some will value the weight savings more.
 
On a 182 with the battery in the back, would there be less benefit owing it being already nose heavy? On the other hand, having such a long and older (corroded) battery cable replaced might be additional weight savings, as well as better cranking ability.
 
Also 1/3 the amp hour capacity.
Please show your math.

ETX900 is 15.6Ah. Concorde RG-25 is 22Ah (71%). RG25XC is 24Ah (65%). RG35A is 29Ah (53%). RG35AXC is 33Ah (47%).
 
On a 182 with the battery in the back, would there be less benefit owing it being already nose heavy? On the other hand, having such a long and older (corroded) battery cable replaced might be additional weight savings, as well as better cranking ability.
With the P I’d probably end up needing ballast in the tail if I moved the battery forward. I don’t come near my GW even on long, loaded out, trips With full fuel. I do calculate WB, I fly out of a 2,000’ grass strip.
Know of some early 182 owners who would give their left testicle for 26 lbs.
 
Well, I ordered one. I'll let you all know if it sucks.

FWIW; there's a discount code that expires today (8-4)
 
This is a concern. The battery for my plane is more like half. Doing a little research into it, it seems like lithium batteries have a very flat discharge curve, maintaining voltage until they are empty, and doing so consistently even at higher draws. Apparently a 35AH L/A will provide 1 amp for 35 hours, but increase the load to 15A and it's far less than the 2 hours you'd expect, with the voltage dropping off faster as well. Supposedly the EarthX was sized to provide a similar usable reserve to the original L/A. TBH if the choice was between a 5lb 15AH battery and a 10lb 30AH, I'd take the latter. As it is, they show an hour or reserve at 15A, which is about what my plane runs normally. I always assumed I'd get about 30m out of my L/A, so I guess I'm comfortable with that.

Remember, L/A capacity checks are done at 1C, so a 35 AH battery is run at 35 amps for 1 hour to not hit a specified voltage limit.

IMO, they should double the capacity and weight. Still a goodly weight saving over lead acid.

BUT, on my Mooney, the issue is forward CG, so a lighter battery would need the additional of Charlie weights in the tail. :D
 
Remember, L/A capacity checks are done at 1C, so a 35 AH battery is run at 35 amps for 1 hour to not hit a specified voltage limit.
Didn't know that; good information
IMO, they should double the capacity and weight. Still a goodly weight saving over lead acid.
Agree wholeheartedly
BUT, on my Mooney, the issue is forward CG, so a lighter battery would need the additional of Charlie weights in the tail. :D
The 3 bladed prop on my plane put my empty CG way forward; to the extent I've seriously considered finding a 2 blade prop to put on or spending the 18K for a composite MT prop. I can't put anything but pillows & blankets in my front baggage compartment, so taking 20+ lbs out of there is huge for me.
 
Remember, L/A capacity checks are done at 1C, so a 35 AH battery is run at 35 amps for 1 hour to not hit a specified voltage limit.
Actually, IEC 60952 defines tests at C1 as well as 10x ("rapid discharge capacity"). This typical lead acid battery has a rapid discharge capacity roughly half that of its C1 capacity.

For lead acid, the end point voltage (EPV) is defined to be 1.67 volts per cell (10v for a 12v battery, 20v for a 24v battery).

They also define C1 tests at 23c, -18c, -30c and 50c. I haven't seen those results from EarthX yet.
 
So if you bought a new battery 25 pounds lighter how do you determine/document your new CG and weight and balance?
 
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So if you bought a new battery 25 pounds lighter how do you determine/document your new CG and weight and balance?

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"I" won't.

That's my mechanic's job. Right after he runs the vent hose, installs the status LED, and sends the STC to Oklahoma city.
 
I’ve had an Earth x in my RV for 3 years now. Stone stock reliable, cranks my motor over faster, and I did lose an alternator with it once. Left the radios and screens on. Landed about 15 minutes after. Shut down. Fired back up. Taxied across KCIC to the mechanics shop and still had plenty of juice for one more start up. Never needed to kick in my back battery. I’m a believer.


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If you want for double capacity? Put in two. Guys with exp airplanes that use EFI have been doing it for years. Run them on a bus manager so one is a dedicated backup. Easy peasy. I prefer to use a TCW IBBS for my panel power backup and power conditioner. No need for a second battery.
 
The 3 bladed prop on my plane put my empty CG way forward; to the extent I've seriously considered finding a 2 blade prop to put on or spending the 18K for a composite MT prop. I can't put anything but pillows & blankets in my front baggage compartment, so taking 20+ lbs out of there is huge for me.

My battery is in the tail, so lighter means the CG moves further forward.
 
So if you bought a new battery 25 pounds lighter how do you determine/document your new CG and weight and balance?
It’s pretty straightforward. You take the old battery moment (weight x arm) and subtract it from the aircraft’s weight and balance. Then add back in the new battery’s data.

Here’s an example from when I replaced an Odyssey with an Aerovoltz lithium iron - which was still going strong for about 8 years when I replaced it proactively with an EarthX. Added a fire extinguisher at the same time.

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Note: I’m EXPERIMENTAL, so I’m responsible for this sort of thing. With a “certified” aircraft, it’s up to an A&P to do it, or at least supervise and sign it off. Still, good to know the procedure so you can double check the math.
 
Saving 10# up on the firewall sounds good. I just put a new battery in last year, when it craps out I'll look at the lithium, hopefully and bugs have been worked out by then.
 
Lithium battery fire risk is 0?
It's all relative. Not all lithium battery formulations are the same. EarthX uses lithium iron phosphate (LiFePO4). It's safer than lithium batteries you see in scooter fires that make the evening news, which typically incorporate cobalt and/or manganese.
 
I just went throught this debate on my Colt as the Gill battery wasn't holding a charge. Anything requiring paperwork means I have to get the local IA to sign off on it and he has his own bills to pay so he doesn't work for free but his prices are reasonable.
To me the options were:
1) Concorde- Install I can do with no additional paperwork. About $450 total cost. Good reviews and W&B remain the same.
2) Odyssey J16- Requires paperwork and a small mod to the battery box. Shaves 15 lbs off the total weight. Cheapest battery but with paperwork total cost is $700. Great reviews with many people reporting 10+ years on the battery.
3) EarthX- the lightest of all battery options that would shave 25 lbs off total weight, also requires paperwork. Included STC has all the stuff to "mod" the battery box. Most expensive battery of the options and with paperwork total cost would be around $1500.

I went with the Odyssey as I figured it was the best overall cost vs reward. The STC for it required me to make a strap to hold the battery in place but it took about $10 in parts and the longest part was waiting for the paint to dry.
 
I talked to them at osh and they mentioned the stc's being approved. I figured I'd wait until my current battery dies, but now that I see it's 25 pounds lighter :yikes:, in the nose where I need it most, I'm thinking I'm just going to order one. By FAR the cheapest dollars/ useful load gain available.
Cheapest or easiest? Most of us could gain some useful by getting closer to that FAA standard adult.

Interested to hear how it works out. Unfortunately my Gill went Tango uniform a few months ago and my dad's Concorde was coming up on 5 years old. I kindly took his core off his hands and he bought a new Concorde.
 
Cheapest or easiest? Most of us could gain some useful by getting closer to that FAA standard adult.
You're not wrong. I managed to take off 25 a few years ago, but the second 25 has proved to be more stubborn. And these damn kids just keep getting bigger :rolleyes:

Funnily enough, suggesting to Mrs. K that we could save $1000 on a battery if she lost 20 lbs didn't go well, either....:dunno:
 
Just replaced the battery in my 182P and considered the EarthX.
EarthX $900, 5.4 lbs, 15.6 Ah.
Concord $500, 32 lbs, 33 Ah.
For me the capacity of the battery outweighed the weight savings flying IFR.
I did a capacity test on the Gill 35 I removed. It was 13V 24 hours after charging but down to 16 Ah capacity (23 Ah new). Plane was getting slow to start with the 5 year old battery.
Some will value the weight savings more.
For a light sport however, that can be a significant savings in weight, if you can make it work out on the w&b.
 
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