Has anyone tried to fit the ETX900-TSO battery into their current C-180/185 firewall battery box?

I just ordered an airglas extended baggage kit and I have an uninstalled F. Atlee battery box and SBS J-16 battery in the hangar. Any weight I can loose off the nose of the airplane will help a lot at this point.

The width of the SBS battery is 3.01in and the Earthx is 3.1in. The rest of the dimension are smaller so hoping it will squeeze in there. The battery box sold by earthx won't fit around the engine mount nicely like the atlee box.

Yes it will fit the Atlee box. You will need to lube it a bit to get it to slide in. Snug is good description as to the fit. It bulges the box a bit and that might be a no-no depending on who you talk to. I know someone who has this set up for two plus years now and zero issues. YRMV

It won’t fit in an FA box if you have any kind of mechanical sense. However, if you send me a PM, I can give you some insight as to what someone with an unknown tail number did.

Looked online, ETX900 is 166mm x 79 x 168.
Odyssey SBSJ16 is 181mm x 76 x 167.
So EarthX looks to be 3MM thicker.

Not sure after looking at EarthX website whether they actually have the TSO in hand for this battery or not.

https://earthxbatteries.com/shop/etx900-tso

Once they get the TSO, what's the consensus re installation--
minor alteration or field approval required?
At the least, looks like a revised W&B would be required
as it's apparently about 10# lighter than an Odyssey,
and 18# lighter than a Concorde RG25.

I spoke to the DER working with earthx on the STC. Sounds like an STC for a firewall install is a ways out but an STC for a tail install isn't too far away.

The Denver FSDO hasn't approved field mods for the battery installs yet. A fairly sizable amount of testing will be required before the firewall stc is out there. Looking forward to getting one of these as soon as I can. I think I'll install the SBSJ16 box for now tho.

BazzLow wrote:….Sounds like an STC for a firewall install is a ways out but an STC for a tail install isn't too far away.....

Not sure what you mean by "STC for a tail install"?
I'd guess that's just to replace the existing battery, but in the stock box / location vs a different location?
That would seem to be all someone would need if they already have the new battery location approved for an Odyssey.

My guess on this is that the battery, independent of location or box, requires an STC or field approval. Installation diagrams show a panel mounted low voltage light and an adjustment to the voltage regulator, and a remarking of the voltage indicator. To me that is STC terriroty regardless of what box the battery is put into. I do believe there is a TSO, but since it isn't just a drop in replacement of a Odyssey or Concord it would require the additional approvals.

That is my best guess from my understanding/conversations with EarthX and my IA.

What's the latest on this earth x firewall situation for the 180? Two STCs? Forget it? Thanks.

One thing to know with the Earth X, it does have a fault detection light that needs to go on the instrument panel or if you have a glass efis, it can go there as well. At least the Dynon D180 had an imput for it, so it won't be a simple swap. The power from a Odessey to the Earth X is pretty incredible, as is the weight savings.

Any update on this? I heard from someone at Oshkosh to expect an announcement soon about an STC to allow earthX on the firewall.

I stopped by the Earth-X booth at Oshkosh and they said to expect the Cessna 180/185 STCs in the 3rd quarter of this year. They had a sign there with a list of upcoming STCs.

Anyone who has paid much attention recently has a pretty good sense what any notice that says “STC approval expected this…..” means. Generally it means they are hopeful.

The reason that a LiIon battery requires an STC is that the provision in the regs that specifies batteries specifically states “any approved lead acid battery” or words to that effect.

The Odyssey battery is pma’d, this “approved”, and since it’s a lead acid……

The Earth X batteries will require an STC, even if the are an “approved type”.

MTV

pipeliner wrote:I stopped by the Earth-X booth at Oshkosh and they said to expect the Cessna 180/185 STCs in the 3rd quarter of this year.

I also stopped by and received the same update. Further, they have a new, resized battery that mimics the Odyssey's dimensions. I learned this when discussing the firewall battery boxes that so many Skywagon drivers have. They are specifically going to target the Odyssey-sized boxes with a drop-in, new sized EarthX (still STC'd though).

wagonflyer wrote:

pipeliner wrote:I stopped by the Earth-X booth at Oshkosh and they said to expect the Cessna 180/185 STCs in the 3rd quarter of this year.

I also stopped by and received the same update. Further, they have a new, resized battery that mimics the Odyssey's dimensions. I learned this when discussing the firewall battery boxes that so many Skywagon drivers have. They are specifically going to target the Odyssey-sized boxes with a drop-in, new sized EarthX (still STC'd though).

That would be great but no 170 on the list. I guess numbers driven.

daedaluscan wrote:That would be great but no 170 on the list. I guess numbers driven.

I contacted them yesterday after seeing this to inquire about the PA-22:

Hello Zane,

Thank you for your email! We do have the PA-22 on the list as well and we are pushing ahead as fast as the FAA makes it possible. I do not have a good timeline to tell you at this point as we have so many aircraft on the list that is in process, sorry.

Hard to believe the 170 isn't planned as well.

What is the weight difference between the Earth-X and Odyssey?

Odyssey SBS-J16 is 14.8# and the Earth-X is 5.4#. Pretty significant.

Ross

3rd quarter ends in September and is just a little over a month away. Still not holding my breath.

I wonder if 3rd quater means calendar, fiscal, or FAA quarters? Ugh.

It's good news that they will offer a SBS-J16 size change - but I'd really rather install the EarthX box that is insulated. Seems like a better option for longevity.

soyAnarchisto wrote:3rd quarter ends in September and is just a little over a month away. Still not holding my breath.

I wonder if 3rd quater means calendar, fiscal, or FAA quarters? Ugh.

It's good news that they will offer a SBS-J16 size change - but I'd really rather install the EarthX box that is insulated. Seems like a better option for longevity.

But then that requires an STC for the box…..

MTV

soyAnarchisto wrote:....It's good news that they will offer a SBS-J16 size change.....

I think that's pretty smart of them.
They will likely sell a lot of batteries to people looking to lighten up their odyssey-equipped airplane by close to 10 pounds.
Maybe even me.