Another Light Weight Battery Option

porcuypine said:

Second report after my first couple weeks using the earthX ETX36D in Alaskan winter ski plane ops.


I made a up a nice set of cables to install the battery in my stock piper 1961 gill 35 sized box but it turned out I did not need them. A few years ago I had replaced the original corroded battery connectors with NOS ones from Unavair; basically a coper web strap with a stud penetrating the box. The reason I mention this is it turned out factory cables were a perfect fit onto the 36D mountings and I did not need the cables I had fabricated. The web materiel is very flexible and this will keep the stress in the battery terminal to a minimum; a posable problem area with this battery.


The first cold weather start with the battery it was 7 deg F but I had not preheated the engine as well as I would normally. The first two starts the prop turned over slowly about four blades each start. I didn't know I had under primed her so I spent the next five minutes I cranking her around and it was really spinning the prop fast. I was wondering if she was over driving the impulse coupling. I then spun the starter about three lead acid batteries worth. No ****! Now that the battery had warmed up internally it was putting out the amps for all it was worth. I have the Skytech in line something NL starter. I was just sitting there wondering when the battery would run out of juice when I said to myself, I do not smell any fuel??? She is not flooded. I pushed in eight strokes of my short primer, pushed the starter button, then she popped into life! I figure the prop was spinning so fast it had cleared the prime before wanting to fire. Hard to say with all the other variables.


The next real cold start it had been -7 degF, the first time I pushed the engine starter button the starter just buzzed, the prop would not pull through a compression stroke; three times in a row. Hmmm? I sat there a moment scratching my head. I turned on the lights, all LED, and radioes to get some current flowing through the battery to warm it up; SOP for lithium iron batteries in the arctic. The next time I pushed the button she spun all the way around slowly and then the engine caught. My girl usually fires, in the winter if well warmed and properly primed, on the third blade with the strong arm. After warm up and short taxi to fuel, sitting uncovered, say fifteen minutes, she hot starts with full throttle and the starter sinning the prop fast.


A couple more cold morning starts and the same thing, barely turning around, or not, at first but then spinning the prop around like the plugs were out! I am not sure I like it and am not sure how this low speed stall of the starter motor will affect the starter itself. Could it be arcing/cooking the commutator? Usually when it gets below zero I hand prop the first start of the morning anyway out of habit because of the old starters and their hanging bendex, you know, if one misses the start miss priming or whatever.


After the first start I mention above, where I spun and spun and spun the engine, I noticed the ammeter showing a solid plus 30 amps! After taking off I like to make a climbing turn around the pond in the winter just to make sure everything is warming up and working properly. It took about four minutes for the ammeter to drop to 20 amps where it stayed for about ten minutes more which was when I started having to aviat, talk to tower, and stopped looking at gage. I noticed after a handful of takeoffs that she was showing 20 amps and then the one time I could stare at the gage it just stayed charging at 20 amps for about 10-15 minutes then quickly dropped to < 1 amp. I have an older InterAv alternator which has worked flawlessly for years but wonder how asking it to kick out 20-30 amps or more is going to affect its longevity? I was thinking a generator or one of those light weight alternators might get cooked trying to actually crank out thirty amps for more then a moment.


I really only have about fifteen battery starts on the battery right now. My bird lives outside all winter up here in western Alaska were I will fly if the temperature is down to -20 degF. the battery will be exposed to -40 degF. I am thinking I should keep a new Gill-35 on the shelf just in case but will keep using the earthX battery because I think in the long run it has the potential to be a big improvement. Time will tell.

Ok, not so short.




Rocket

Click to expand...

I bought an Earth X ETX 36C in looking at the paper work it sayed don't charge over 10 amps. I was wondering about my alternator putting out 30 amps & damaging the battery? Sounds like you have had it happen with no problems?

AK,
when I read the 10 amp charging rate I assumed it was for bench charging.

Decided it was a good idea to call earthX. Spoke to, ...darn forgot her name, anyway had a nice talk and was informed that the 10 amp was indeed meant as a maximum bench charging rate. It seems some of the less edgumacated, ie: sled drivers, were trying to charge with 80 amp garage chargers and having a little trouble.

She did mention that some of the cub drivers were wanting to use the smaller 18 battery of theirs and she said it would not like charging at over 30 amps and thought the 36 battery was the best all around option for our "uncertified" aircraft. She also mentioned that they were hoping to be at the Alaskan Airmen's trade show in Anchor town.


Rocket

So far so good with 40 hrs of ski flying with the little EarthX. Only low 40's starts but it seems real gutty. Nothing to not like about it except the price, and a couple hundred extra bucks for over 10 lbs. less weight is OK with me.

courierguy said:

So far so good with 40 hrs of ski flying with the little EarthX. Only low 40's starts but it seems real gutty. Nothing to not like about it except the price, and a couple hundred extra bucks for over 10 lbs. less weight is OK with me.

Click to expand...

18 or 24c ?

Glenn

36c

I just realized I never put out a report on my Earthworks....

I installed Earthworks batt ETX36C (the C or D after the 36 is just a dimensional difference) in April of last year. So, I'm nearly at a year on the battery....

I love it. It's extremely lightweight and cranks harder and faster than the Oddesey it replaced. I just had a battery failure/warranty replacement three weeks ago which I'll describe in a moment. The company was very fast to have a new battery in the mail and with return postage to analyze my failed battery.

I really like the BMS - Batter Management System on this battery that balances the cells for you during charge. No special chargers required like most Lithium batts. It also has a current cut off at 6 volts to make sure you can't completely run the batt dead. If you do run any of these Lithium batteries to dead, they die and are now throw away, order a new one. I like the cutout saves the batt just before it dies anyway. Leaving on your battery master switch accidently will not cost you another $340.

Operating:

There is absolutely no difference operating this battery that I can tell, save one. After start as I switch on the alternator, this battery draws much more for a shorter period of time. As the alternator comes on, there is a audible drop in RPM (10-20ish RPM while idling near 1000) as the engine takes the load. A look up at my Ammeter shows about 25-30 amps load for about 10-15 secs, then back down to 2-3 amps. Presumably, it's all charged again. The lead acid used to charge much slower, for longer.

I've enjoyed the battery all year. It's more compact. It sits right under the seat, so no CG change but it's light and powerful.

I like the terminals in the center edges of the top, so it's a universal fit. My odessey had terminals in the upper corners, so you had to be careful which battery config with positive right or left when ordering. The earthworks can be laid on either side, or reversed right or left to switch terminals to side it's needed. They have screw in posts that work with a #2 Phillips driver and you can leave your #10 metric wrench at home (Odyssey).

A few weeks ago, it was cold for here, 19deg F. Plane hadn't flown in about 5 days. I did my best preheat. These batteries are not like lead acid, which gradually loose power when it's colder. But, the engine is arguably harder to turn over, and the battery becomes more efficient as it gets warmer. So, A warmer battery does better. I turned on my landing light for 10-20 secs as I remember instructed by a lithium batt guy. I switched off light and went right to cranking. It was slower to turn. Got hung up on a compression stroke. I popped the switch a couple times to help cut through the compression and I smelled a little elect smell. Strangely, the battery still showed 13.4 volts on a meter, but it didn't have enough push to even light up my electrical..... They replaced it immediately. In reporting back, the company said my battery had been overcurrented and cracked the circuit board. I had overcurrent(ed) the BMS circuitry. The new batts Battery Management System will also prevent that now. The company is constantly adding improvements to these batteries to make them better.

I really appreciate the cold weather reports that you guys are doing for this battery as it makes me pay attention to best starting practices.

After speaking with the Earthworks people, they stated I should have let the plane set for a couple minutes after the landing light drag to allow the heat to warm though the battery (OR done that during preheat). Lesson learned.

I love the battery. With it's cost, I'm not anxious to buy another. I hope this lasts a long time. The batteries have a one year warranty and they were very good in my warranty claim.


I usually talk to Karen, but have talked to others. They're closed on saturdays, but they've called me back on a Saturday when I left a message. This company is getting all kinds of attention from pilots. They are trying to learn our needs and adapt to them as quickly as they can. She complemented and complained that we're so much more technical than their normal customers The Supercub guys and the Rans guys are really the main aircraft drivers of lightweight battery and most of their aviation business. As reported, they will be at the Alaska Airmans show in May and looking to develop this business. They have an even larger battery under development specifically for aircraft and are trying to learn about certification. Give them a look.

IFL,


Thanx for taking the time to write this up and sharing.


I forgot to mention one key winter ops element the EarthX tech told me. When the sno-go operators are trying to start at -20 deg F the important part of the current draw battery pre heat is not so much the amount of current but waiting a full minute or more before hitting starter button. I know it sounds crazy to us lead acid dinosaurs but this is one minute warm up is the key to having the available current when we need it. Unfortunately this winter has been a bust for any of us Western Alaska ski flyers. With the repeated 40 deg F out here I have had only a couple occasions to test the low temp starting with the one minute warmup. Pulled the Batplane off the ice and onto the beach yesterday…again.


Unfortunately the one enemy of this battery technology is heat and in particular during the charging process. This means that mounting on the fire wall where it might take advantage of winter preheating devices, like the Northern Companion I use, is not a good idea. I would like to talk to the EarthX people about this in particular as I might be misinformed about this issue.


IFL- A couple question about your over current failure: was your battery one of the newest generation batteries that were do to ship around April of last year, 2013,? Did Karen say specifically that your new replacement battery had an over current protection element in it now?


To tell you the truth when I was looking at the numbers for these batteries I was thinking that two of the 36 batteries in parallel would really be perfect, if not a little overkill, for our application. If I was inclined to use them in something with a big continental I think two ganged together should work perfectly. Might be a little rough on the pocket book but still way less then one AMU (Aviation Monetary Unit of $1,000.00) especially if one needs to be replacing their lead and acid ballast anyway.




Rocket

Am pondering the possibilities one may encounter by running dual Light Speed mags and with a single battery with a low voltage cut off such as Earthworks. Single Earthworks and dual LS mags would seem to be a risky combination should things suddenly go south. Single Ballistic battery with dual LS mags still risky but may be a little less so because even though it will trash the battery you can still run it dry. I would much rather land safely with a trashed battery than in the trees with 6 volts remaining and could not use. I would assume that with dual LS mags, dual batteries are be the best bet. I am sure we would all eagerly fork over the cost of a new battery when things go silent. The project has 2 Ballistic 8 cell batts, one for each mag. Battery voltage indicators are also real handy, as single mag operation can extend your range without much loss in airspeed.

As far as leaving or inadvertently bumping the master on, I leave my pulsing landing lights on when ever I am flying, it's pretty hard to walk away without seeing the gear mounted landing lights flashing even in the daylight.

porcuypine said:

AK,
when I read the 10 amp charging rate I assumed it was for bench charging.

Decided it was a good idea to call earthX. Spoke to, ...darn forgot her name, anyway had a nice talk and was informed that the 10 amp was indeed meant as a maximum bench charging rate. It seems some of the less edgumacated, ie: sled drivers, were trying to charge with 80 amp garage chargers and having a little trouble.

She did mention that some of the cub drivers were wanting to use the smaller 18 battery of theirs and she said it would not like charging at over 30 amps and thought the 36 battery was the best all around option for our "uncertified" aircraft. She also mentioned that they were hoping to be at the Alaskan Airmen's trade show in Anchor town.


Rocket

Click to expand...

Thanks for the info. I have two starts on my battery & it turns over very well, lost 11.9 lbs off the fire wall!

Well ****! I did it, second day on floats and got distracted beaching and left my master on and drained my Earth X . When I returned from airmen show/Telktna/ruth glacier flying adventure in the Bigwheel, pet name for my spam can, the low voltage shut off had…shut her off. Decided on a NORDO adventure out of the Pond at 5NK to try and shake the rust off for a couple float adventures I have coming up and also wondering if it would just charge during a 45 min flight up and around the river.


I have an Inter-AV alternator system that would self excite off a mostly dead Gill 35 but with absolutely nothing showing on the volt meter I suspected it would not with the EX -battery on LVCO mode.


Pushing her over for for VY I noticed the amp meter sitting at 30 ish. I quickly made sure I had all the loads on and then laughed because I'm all LED anyway. In some aircraft, Beaver comes to mind, you can smoke the battery/alternator if you let it charge a mostly dead lead acid battery full amps so it is important to maximize the load to slow the current being fed to said battery.


After about a 30 minute flight she was showing a little less then twenty amps but with the sun setting and it being just the third day on floats this year I just wasn't ready for landing in the dusk so I put her away for the night.


So, has any one else OPs checked the low voltage cutoff of their EX battery circuitry or am I the only one dumb enough to share it on line?




Rocket

Well ****! I did it, second day on floats and got distracted beaching and left my master on and drained my Earth X . When I returned from airmen show/Telktna/ruth glacier flying adventure in the Bigwheel, pet name for my spam can, the low voltage shut off had…shut her off. Decided on a NORDO adventure out of the Pond at 5NK to try and shake the rust off for a couple float adventures I have coming up and also wondering if it would just charge during a 45 min flight up and around the river.


I have an Inter-AV alternator system that would self excite off a mostly dead Gill 35 but with absolutely nothing showing on the volt meter I suspected it would not with the EX -battery on LVCO mode.


Pushing her over for for VY I noticed the amp meter sitting at 30 ish. I quickly made sure I had all the loads on and then laughed because I'm all LED anyway. In some aircraft, Beaver comes to mind, you can smoke the battery/alternator if you let it charge a mostly dead lead acid battery full amps so it is important to maximize the load to slow the current being fed to said battery.


After about a 30 minute flight she was showing a little less then twenty amps but with the sun setting and it being just the third day on floats this year I just wasn't ready for landing in the dusk so I put her away for the night.


So, has any one else OPs checked the low voltage cutoff of their EX battery circuitry or am I the only one dumb enough to share it on line?




Rocket

Haven't left master on yet.. Like the new battery so far tho.. Cranks hard..
So did it charge back up ok?? With just alternator??

Double..

Here's where I recently re located my new little Earth X. Previously under the pass. seat (experimental Rans S-7S), in the same box I had the Oddsey battery in, along with some foam shims to make it fit, it fits PERFECT between my rudder pedals, right up tight to the parking brake valve/firewall (with a little pad in between to protect both). I first made a same sized cardboard mock up and hot glued it in place, and then went flying. An hour later I remembered I was testing the location, too see if it got in way, then I realized that since I had forgotten all about it, testing was complete! I've flown 8.5 hrs on 3 different flights and it just isn't in the way, period. I have since taped over the positive terminal by the way.

Check out the battery box: ain't one. The floor and firewall were already there, the parking valve (whose lever clears by about 1/8", couldn't have planned it better) keeps it from jumping up in the air, and three small brackets wood screwed into the ply floor secure it side to side. At the same time, I also got rid of the old electric solenoid, in the back where the battery used to be, and installed a fire wall mounted mechanical disconnect switch from Summit Racing's aircraft division. A pushrod controls it, and I have since finalized and cleaned up it's under the panel mount, just some wire here for test purposes. The picture shows it in the OFF/pulled out position, ON the hadle is an inch away from the panel so out of the way normally.Lighter and NO electrical draw, the idiot proof master! About 2 lbs of weight savings, this is all the crap I no longer needed. Plus I have an empty panel location for a future switch if needed, and a small additional storage area where the old location was.

Here's where I recently re located my new little Earth X

Click to expand...

Looks pretty slick to me. When my Oddessy gets a little older, might have to try an Earth X

My Oddessy was only 3 years old and working great, but the weight savings in going to the Earth X was too much to ignore, and then a further weight savings due to it's small physical size. Plus my ATV needed a new battery and the Odd fit perfect so that sealed the deal.

Question- I have a Concorde battery now in my PA-11. I would like to switch it out for weight reasons. Earth X is only for experimental aircraft. Would they even consider it if I tried to get a field approval?

Sent from my SAMSUNG-SGH-I337 using Tapatalk

Field Approvals are at the option of "they". There are published guidelines, but it is still the option of "they". You need to go to the FSDO and ask "they". Show "they" all of the documentation which you can muster on the Earth X. It would be helpful if you have an IA friend who is on good terms with "they" as well. Since batteries are not required equipment in PA-11s, it may be a bit easier?

Thanks Skywagon

Sent from my SAMSUNG-SGH-I497 using Tapatalk

PA11, My comments above may seem like a wise a$$ remark, but I assure you it is not intended to be. Field Approvals are very political. You do need to be very friendly to one of those folks, in the FAA, who have the authority to approve FAs.

I sent in a 337 once on a float installation. Several months after the fact (it is supposed to be done in 30 days) "my FSDO PMI" called me and said that he had been to "Field Approval" school and that he needed to come visit so that he could issue a Field Approval. So he came, read the log books, looked at the airplane from a distance (had no idea what it was), wanted to see a torque wrench calibration, and decided that he was not willing to sign the Field Approval. Hint: the floats had been installed in accordance with an early 1950s 337 which is the equivalent of a current STC. No field approval required. After he left, a phone call was made and mysteriously he somehow was transferred to Singapore. Bottom line Field Approvals are very political. Be polite, courteous, respectful, etc.

skywagon8a said:

... Field Approvals are very political. You do need to be very friendly to one of those folks, in the FAA, who have the authority to approve FAs

Click to expand...

I would second this. It me took 18 months to get a fairly routine FA on a panel rework: new radios and moving wiring out of the wing root. The first inspector punted after a few phone calls and about 9 months. 2 more took over as a team. Most of the time was spent negotiating what the end paperwork would look like. Even then, I don't think it would have been approved except one of the inspectors had a soft spot for classic airplanes and genuinely wanted to help. The other really wanted to push it to a DER. All this for a change that has clear safety advantages and that many here have proposed should require no more than a logbook entry.

Even so, they made it clear that FAs present only downside career risk; thus, all the focus on paperwork. Inspectors get advancement through enforcement actions. I'm only paraphrasing a little.

Just my opinion, but you would never get an FA for a non-aviation battery with a new chemistry here in Boise without using a DER. YMMV.

skywagon8a said:

Field Approvals are at the option of "they". There are published guidelines, but it is still the option of "they". You need to go to the FSDO and ask "they". Show "they" all of the documentation which you can muster on the Earth X. It would be helpful if you have an IA friend who is on good terms with "they" as well. Since batteries are not required equipment in PA-11s, it may be a bit easier?

Click to expand...

Pete,

I put a battery in my old J 3 in a homemade box. My mechanic called it a "temporary installation". Just because it's sorta fastened inside an airplane doesn't necessarily imply it's "installed".

MTV

That is true Mike, It depends on how it is held in place, there is sometimes a rather fine line. The question in this case was "how do I get a field approval?", not "how can I get away with it?".

mvivion said:

Pete,

I put a battery in my old J 3 in a homemade box. My mechanic called it a "temporary installation". Just because it's sorta fastened inside an airplane doesn't necessarily imply it's "installed".

MTV

Click to expand...

Nice to see you mellowing with age.

Glenn

I see this great thread on Lithium batteries, hint hint, was bushwhacked by the high time users... :/

Anyone using the new aircraft specific duel circuit EarthX batteries? They have redundant charge control and high amp protection? Im thinking about the EX900 suitable for the big bore Conti.

Im still rocking my 36D after 24 months.


Rocket

I just got my 36C in the mail this weekend. Hopefully I'll get it on the plane on Wednesday. Way smaller and WAY lighter than the one I have in there.

Looking for the right lightweight solution for an 0-360. Thinking of installing a barely adequate (Earthx 24?) and carrying one of the small jump start batteries with an installed plug.
A quick search didn't reveal any current messages on this topic? Appreciate comments.
Thanks
Peter

They are now making a dedicated aircraft battery

http://earthxmotorsports.com/product-category/experimental-aircraft

Glenn

Yes I have seen these bigger batteries. What I am getting at is what does it actually take on a warm day to crank an 0360. Maybe that is the size I should install and have capability to add power on a winter day with one of the lightweight boosters. Do we need 400 cca in summer?

petercowan said:

Yes I have seen these bigger batteries. What I am getting at is what does it actually take on a warm day to crank an 0360. Maybe that is the size I should install and have capability to add power on a winter day with one of the lightweight boosters. Do we need 400 cca in summer?

Click to expand...

Not bigger, less then 4lb

Glenn