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EarthX Battery in a Rv10, Comments?

maca2790

Member
Hi Guys,

I am thinking about installing an ETX900 in my RV10.

I have had a 2nd Concorde 25Xc fail in 5years. The first one lasted 2 years for 87 hrs of flying. Now this 2nd battery has about 106 hrs on it for 3 years of use.
These batteries are very expensive here in Australia ($640 AUS) and I am seriously considering and EarthX ETX 900 as a replacement.

The Battery cradle will need modification for the EarthX but that should only be a minor like installing a few spacers.

Does anyone have any experience with EarthX batteries in their RV10?

Cheers

John MacCallum
VH-DUU
RV10 41016
 
Hi Guys,

I am thinking about installing an ETX900 in my RV10.

I have had a 2nd Concorde 25Xc fail in 5years. The first one lasted 2 years for 87 hrs of flying. Now this 2nd battery has about 106 hrs on it for 3 years of use.
These batteries are very expensive here in Australia ($640 AUS) and I am seriously considering and EarthX ETX 900 as a replacement.

The Battery cradle will need modification for the EarthX but that should only be a minor like installing a few spacers.

Does anyone have any experience with EarthX batteries in their RV10?

Cheers

John MacCallum
VH-DUU
RV10 41016

I have the 900 as my main battery and a 680 for my ebus. Both are mounted when the plans battery is located. I had previously modified the tray for a pair of Oddessy 680s.

They are working great! Especially when it’s cold outside.
 
I have an ETX1200 in the stock battery box. I had to fab some shims for the box, the top of the battery, and shorter hold down bolts to get it to fit.
 
I have the 900 as my main battery and a 680 for my ebus. Both are mounted when the plans battery is located. I had previously modified the tray for a pair of Oddessy 680s.

They are working great! Especially when it’s cold outside.

Hi Bob,
yes I think I saw you post something about having an EarthX.
Interesting about the 680 for E Buss. I don't have an E buss, I have a back
up Plane Power Alternator driven off the Accessory Pad.

The Advanced Flight Screens have their own back up batteries.

In the Rv14, I am about to start work on, I haven't decided yet on what type of back up but I am thinking of going with the Back Up Alt like in the 10.

How old is your EarthX 900?


John M
 
I have an ETX1200 in the stock battery box. I had to fab some shims for the box, the top of the battery, and shorter hold down bolts to get it to fit.

Hi Todd,
the 1200 has a lot of reserve I should think. How long have you had it?

Cheers

John M
 
5 years

Hey John,
5 years and going strong on the ETX900.
If you will love the effect on your w & b
Cheers
 
I installed the 900 in my RV10 in the stock location. I basically took a piece of wood that fit the stock battery tray and cut a hole in it to match the footprint of the EarthX. Then used the stock hardware to hold it in place. Very easy and works well.
 
I have EarthX in my 10. Only 48 hours of flight though. Happy with it so far.

Here's a few pics of the installation showing the added bracket on the top battery holder to keep it in place. Should I ever want to go back to larger battery, I just have to drill out 3 rivets and the tray is unaffected.
 

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Most RV-10s need some weight aft. What are you builders using the lighter EarthX batteries doing to correct for W&B?

Carl
RV-10 with dual PC-625 batteries mounted in the standard location and very happy with W&B.
 
Most RV-10s need some weight aft. What are you builders using the lighter EarthX batteries doing to correct for W&B?

Carl
RV-10 with dual PC-625 batteries mounted in the standard location and very happy with W&B.

I really haven’t noticed a difference. Even with my old battery, an Odyssey 925, when solo or just a co-pilot I always flew with gear (tool kit, cover, tie down ropes, gust lock, etc) in the baggage compartment plus a plastic 5 gal collapsible water cube. What I like about using water for ballast is I can start with it full and dump if necessary if I pick up pax or cargo Enroute.
 
Hi Todd,
the 1200 has a lot of reserve I should think. How long have you had it?

Cheers

John M

About a year and a half— I went with the 1200 to give me that extra AmpHour capacity for IFR purposes to compliment my dual alternator architecture.
 
Most RV-10s need some weight aft. What are you builders using the lighter EarthX batteries doing to correct for W&B?

Carl
RV-10 with dual PC-625 batteries mounted in the standard location and very happy with W&B.

Airflow Systems A/C tray and Evaporator. :) I went with the earthX to offset the A/C weight in the back. With a single pilot, I need about 7lbs in the baggage copartment to within forward CG, but with some tools and oil, that's easy to achieve.
 
Most RV-10s need some weight aft. What are you builders using the lighter EarthX batteries doing to correct for W&B?

Carl
RV-10 with dual PC-625 batteries mounted in the standard location and very happy with W&B.

30lbs of free weights in the baggage compartment when flying solo.
Alternatively, Tidy Cats in the back seat.
 

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30lbs of free weights in the baggage compartment when flying solo.
Alternatively, Tidy Cats in the back seat.

I thought you carried that cat litter to soak up the oil that it leaks 😁.

In all seriousness, when my odyssey goes I will probably go with the earthx 900 in stock location. So far the odyssey has been flawless though.
 
Looks like only the 900 comes with the VNT option.

How much of a safety issue a non-vented EarthX is considered to be in the standard battery location in the -10 tail cone??
 
EarthX ETX1200 on the firewall

I installed an ETX1200 on the firewall. I went with a lightweight whirlwind prop so I wanted to eliminate some weight out back to keep the plane close to factory W&B figures. It also kept the wire runs short which have a couple benefits that I wanted to take advantage of. With this configuration their insulated, polished stainless steel battery box is a must. I had their original lightweight box with the open face/bottom and there was some evidence of case deformation from heat, most likely after landing because there was never an overheat warning light in flight. I made a carbon fiber box with insulation after that and I would still get the overheat warning once restarted after a quick refuelling stop. I haven't had a problem with the battery getting hot since installing the factory insulated box with a 5/8" blast tube a couple years ago.

In 2018 my 10 experienced a plane power alternator failure (the common stator leg breakage) that took out the earthX battery. I'm not sure what the failure was in the battery but I don't think they are as forgiving of such events as a lead acid battery. Everything still worked and the unloaded voltage was where it should be but it didn't have the same cranking power. It would also drain much quicker when running the avionics on the ground without the engine running. I sent the battery back to the factory for analysis. It was long past the warranty period but they were kind enough to give me a 50% discount. That was still an expensive day but I went with another EarthX (B&C alternator this time though).
 
Hi Colin, thanks for the reply. Interesting about the ETX1200 on the firewall and your efforts to keep it cool. Regarding the Alternator failure, did you have a fuse in the Alternator output line to the battery? How old was it when you sent it back?
 
Hi Bill,
there is a Vented EarthX 900. Obviously they are concerned about a fire in one of these Lithium batteries or they wouldn't provide the Vent system. I wonder how many they have had catch fire?
 
Looks like only the 900 comes with the VNT option.

How much of a safety issue a non-vented EarthX is considered to be in the standard battery location in the -10 tail cone??

Bill I called EarthX and behind the baggage bulkhead is apparently not considered necessary to vent.
 
EarthX on firewall

Hi Colin, thanks for the reply. Interesting about the ETX1200 on the firewall and your efforts to keep it cool. Regarding the Alternator failure, did you have a fuse in the Alternator output line to the battery? How old was it when you sent it back?


I was one of the early adopters if the earthX on the firewall back in 2015. The battery was over 3 years old when I sent it back. Yes, I have a 60 amp ANL fuse between the alternator and the battery. It wasn't an overcurrent condition that caused the battery problem. Considering that one phase of the stator was broken it was probably a high ripple condition or maybe spikes caused by the broken stator wire making and breaking contact with vibrations.

The earthX has an operating temperature range that is higher than most lead acid batteries.
 
Hi Bill,
there is a Vented EarthX 900. Obviously they are concerned about a fire in one of these Lithium batteries or they wouldn't provide the Vent system. I wonder how many they have had catch fire?

This battery chemistry will not catch on fire, it will smoke and that is it. I think the vent is to ensure that the smoke doesn't fill the cockpit. There is a cool video of a battery company showing what happens if you intentionally damage the battery with too high a voltage.
 
Positives:
Light weight 4.5 lbs vs 24 lbs on a convention battery
Good cranking power

Negatives:
Battery is sensitive and along with the BMS it has two failure points battery and/or BMS.
If AOG, Jump starting an Earth X can be an issue.
 
Most RV-10s need some weight aft. What are you builders using the lighter EarthX batteries doing to correct for W&B?

Carl
RV-10 with dual PC-625 batteries mounted in the standard location and very happy with W&B.

A BRS parachute system nicely shifts that CG back. Plus it uses up some baggage space to nicely constrain how much excess stuff your passengers make you carry.

Two big benefits.
 
Teah

Yeah that brs system shifts the cg back, basically eliminates the baggage area, but it will DEFINITELY lighten your wallet...
 
Battery replaced.

Well I looked at the Earthx and I looked at the Odysseys' and I looked at all sorts of batteries. What I found would fit is a Deka Power Sport ETX30LA.
No modification and fits snug as bug. 30 AH, 400CCA and about $700 cheaper than an Earthx and around $400 cheaper than a Concorde 25XC (hear in Australia. So I will see if this lasts more than 100 hours of flying!
 
$$$

There is generally a reason for such a difference in price...

Beware, ESPECIALLY if you are running an electrically dependent engine...
 
G’day Bob,
Yes I would normally think that logical but the Concorde 25XC has proved to be unreliable and so I shall give the Deka a try. If the Deca starts to do what the Concorde does, which is drop it’s voltage when cranking to less than 7 volts, I will do something else. By the way I have Magnetos and a Plane Power backup Alternator.
 
I've had an EarthX mounted to the firewall of my -10 for 3 years now.

Initially had an issue with heat, the battery was replaced by EarthX. I built an aluminum box that is connected to a small blast tube and added a shield to the R exhaust and have had no further issues, >200 hours since then. This was before they had their custom insulated box available.

I am very happy with the battery and my CG. With me solo and no bags, I am just behind the max fwd CG. To me this is optimal, as basically anything I load is aft of the CG, and it allows me to carry as much as possible. I do a decent amount of solo XC, and often carry a lot of heavy stuff.

If I am flying solo for fun, my toolkit in the baggage area (about 25lbs) makes full aft stick on landing a bit easier. However, it is not hard without aft ballast.

Thomas
 
Most RV-10s need some weight aft. What are you builders using the lighter EarthX batteries doing to correct for W&B?

Carl
RV-10 with dual PC-625 batteries mounted in the standard location and very happy with W&B.

Depends on the prop. Not so with the MT. Been running the ETX 1200 for years in the 10, and have installed many in other RV-10's.

Vic
 
I switched to EarthX 3 years ago and so far so good. I love the weight loss and starting power.

The more I learn about the LiFePo4 cells the more I like them and trust them. EarthX uses prismatic LiFePo4 cells which will typically be 4 larger cells wired in series to get the 13.2 volts. Could be more cells if they are a custom voltage. I am sure someone here knows all the facts. Here is a teardown of EarthX. Not sure if this is a current model. EarthX Teardown of failed battery.
I wish the cells were better supported than just some foam.

I have really enjoyed watching videos like the one below from Will Prouse to learn about how these batteries are built. In general, they are very simple to build yourself and I plan on replacing my boat batteries this year with some homebuilt batteries. You can build a very nice 100ah battery for around $500 with a nice BMS (battery management system). They are either assembled with smaller individual cells like the Battleborn in the video below or prismatic cells (second video). Prismatic cells are much easier to use as a hobbyist since you don't need to spot weld them.

Battleborn teardown
https://www.youtube.com/watch?v=G5E30u-66VI

Example of prismatic cells.
https://www.youtube.com/watch?v=eJaK7fJ4gQU

Honestly, I would have not issues building my own batteries for my plane. I think I could do a better job, use a better BMS with GradeA prismatic cells.
 
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RV-10 EarthX batteries in the rear. It seems that there should be enough natural draft to not need to vent Earth X batteries in the rear of the 10? Any suggestions on venting?
 
RV-10 EarthX batteries in the rear. It seems that there should be enough natural draft to not need to vent Earth X batteries in the rear of the 10? Any suggestions on venting?

Venting is only applicable to the VNT versions and is there to support a thermal runaway. For the straight up ETXs there is no venting requirement and is a non-issue IMO.
 
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Well I looked at the Earthx and I looked at the Odysseys' and I looked at all sorts of batteries. What I found would fit is a Deka Power Sport ETX30LA.
No modification and fits snug as bug. 30 AH, 400CCA and about $700 cheaper than an Earthx and around $400 cheaper than a Concorde 25XC (hear in Australia. So I will see if this lasts more than 100 hours of flying!

That Deka is a 22lb AGM lead acid battery. So it's kind of an apples and oranges thing to compare to to a lightweight Lithium Iron Phosphate battery.
 
EarthX Thermal battery box

RV-10's with installed Air-Con often move the battery and electrics forward from the stock location, especially if there is an added Yaw dampener in the aft location. It helps restore the aircrafts rear most CG station.
( all builders should do the CG calculations on the effect of moving around installed components on their build)

Great results fitting the Earthx Thermal battery box on an RV-10 FF.
https://earthxbatteries.com/shop/thermal-battery-box-etx680-900-900-vnt-1200

Testing through multiple flights show the shut down temps did not exceed 60 Deg C

AM-JKLVUpzUNrFTBsHlwogPCn3EVekdtee6ULqhAbMfkPiOnjeG3d7rHq8YdMYqbFiif9ZYdy4grHON45ZMp9geLtSOGAHpaity5lIFxIlsA985KPVQDXLTEAx3wDW2zIwLSN2IXtFEmteJXoNwjIem2QZqc9Q=w1205-h903


Blue trace is inside cowl temps.

AM-JKLVGSc4p8HqZT1eHEF1NvLIuBMhcSajyFCuhYEL_yjo88zSSz2Ng1Vk1ZvvrbSknwP1ft3pTUUfzOQ4FDHmdtgqMiEBPN3hr4c3xPjM6Yn8if0nCUbCFI1LGQWg-VrLEIjB1WfCSAUpZLx4sK1VeGC2VMA=w678-h903
 
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Weight and Balance using Earthx on RV-10

I have an ETX680 in the RV-9A I share with another pilot and love it. We just put it in a few months ago. It replaced an Odyssey PC680 battery that failed twice.

I plan on using 2 EarthX batteries for my electrically dependent engine for my RV-10 (ETX1200 is my current though). I will have less weight in the rear. I also just ordered a Whirlwind 300-3B/B-77 propeller that will save 12-16 pounds on the nose.

Mike


I went dual ETX-960VNTs in the stock location (with a custom bracket). I have a MTV-9 up front. Here is a link to my weight and balance:

https://karrelsj.blogspot.com/2020/10/it-is-getting-real-now-with-everything.html
 
I will have less weight in the rear.

BUT in my opinion you need that weight in the rear of RV10. When it is just the two of us, I carry 50 lbs of lead shot in baggage compartment. I remove it when we have baggage or people in back seat. Just my opinion based on 10 years and 1000 hours of flying our RV10 around TX and the country.
 
BUT in my opinion you need that weight in the rear of RV10. When it is just the two of us, I carry 50 lbs of lead shot in baggage compartment. I remove it when we have baggage or people in back seat. Just my opinion based on 10 years and 1000 hours of flying our RV10 around TX and the country.

It’s manageable. I have the 1200ETX which replaced an Odyssey 925. I too fly with ballast, a 5 gal collapsible plastic camping water cube that I’ve been using since my first flight almost 7 years ago. That gives me 40 lbs and I haven’t noticed a difference in the flying qualities although the empty cg did change slightly. YMMV…
 
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Air-Con RV-10's,FWF batteries and rear CG

Hello Tommy and all,

The main reason for moving the battery to the firewall has been to off-set the small increased rear CG effect of installing the A/C. This is also compounded by builders also adding in Yaw Dampeners.

Mounting the EarthX battery and associated electrics on the firewall does a great job of restoring rear CG capability of their RV-10.

It is the builders reasonability to do the math and understand what implications there are of installing various components in different locations of the aircraft.

ie the last A/C equipped RV-10 I was involved with with a FWF battery had a placarded limitation of carrying 20kg in the baggage hold for single pilot and low fuel. This aircraft with 4 x people and loaded to gross was a delight to fly and no threat of loading through the aircrafts rear CG limit.

Please do the math during your build, there are many build sites that have great spreadsheets that make it easy to understand your equipment choices and effect on CG.
 
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