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Picked up an earthX LiFePo4 battery at Oshkosh

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Well Known Member
I picked up a LiFePO4 battery at Oshkosh from earthX, model ETX680. I Installed it at the show and now have a bit of time with it for evaluation.

It is amazingly lightweight... 4.12 pounds on my scale! This replaces my 14.4 pound PC680 AGM battery. A real savings of more than 10 pounds. Crazy.

The form factor is very close to the PC680 and the idea is to use the existing battery box. This works with a couple of notes. The earthX battery is about an inch narrower and just a smidgen thicker and when first installed I had to rock it back and forth in the box to get it in and could not get it to seat all the way to the bottom. Initially it looked like it might not ever come out!

After flying nearly nine hours home it worked itself into the box and now slides in and out just fine.

The terminals are center mounted so I had to fabricate new hold downs. I made a couple of tabs out of .063 using the existing nut plates. This worked out great.

The battery from right out of the box had a strong charge and delivered around 12.8 volts to the bus. During my departure the alternator was flowing around 25 amps to charge, that dropped off gradually and after 40 minutes or so it was fully charged. Pulled from the plane with a full charge my meter shows 13.7 volts.

The chemistry for this battery is quite a bit different than a traditinoal lead acid. The battery will not fade voltage as it discharges or comes under heavy load. It will hold and deliver close to the rated voltage until it nears the end of its capacity. Very different... even cranking the starter the voltage on the bus was above 12!

Apparently, any lithium based chemistry is based on 3.3 volts per cell and there are 4 to make up a 12volt pack; actually 13.2. It is critical that these individual cells be managed for charging. EarthX uses redundant built in charge management circuits within the outer case and includes a remote status indicator and contact. The indicator or the case faces the firewall and I have not yet connected the contact to my panel.

There has been quite a bit of discussion about the safety of Lithium batteries in general... the advantage of the iron phosphate derivative is its thermal and chemical stability.

https://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery

Fly Low, Go Fast, Turn Left ;)

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Just wanted to put another data point out there. We have been flying with the EarthX for almost a year now and it is solid. No complaints at all and the weight savings is great especially in the back of the -10 where aft CG issues can be a challenge sometimes.
 
I went with the ETX36 because at the time the ETX900 didnt exist. If I were to do it again now I would do the 900 since it has redundant electronics and a fault monitor and a little more power too. I previously had the Odysey 925.

To make the battery fit I cut the two bolts that hold the battery down and re-tapped them and then I drilled a couple holes in the bottom of the battery box and pop riveted on a piece of angled aluminum right up against the new battery to make it fit nice and snug. I think you could make any battery fit pretty well and pretty easily this way in my opinion.
 
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Quick question for everyone here.

I was also at the show and saw a few lithium companies, but I wanted to find out some things about them first.

Biggest question for me is where the battery is built. I have purchased lithium batteries in the past, and for the most part they've been built in China or Korea - and those didn't do well. I've come across some companies that put "Made in the USA" but it was really made in China despite that claim, they only put stickers on it or some other nonsense.

I can't find a definite street address, just a PO Box from them, and the only address I did find was for someone's house.

Can anyone help me to verify these guys so I can feel confident about them over other companies? I'm looking around, would like to feel safe about losing that weight.

Thanks!
 
I went with the ETX36 because at the time the ETX900 didnt exist. If I were to do it again now I would do the 900 since it has redundant electronics and a fault monitor and a little more power too. I previously had the Odysey 925.


Hi Brian. I will probably go with the 900. Just want to know, Does it swing the prop of the io-540 well or you feel it's underpowered?
 
Thanks for the review.

I swung by Earth-X a few times at the show as well, but just couldn't put a bullet in my old 680 yet as it still swings the prop with gusto. I hate putting something that still works well out to pasture, but when it gives me the slightest inkling of starting to croak, Earth-X's product will be at the top of my list...

Now, if only it was as easy for me to lose 10 ugly pounds with one swipe of the credit card as it is for the RV!

Please keep us updated on your experiences...pro and especially, con.

Thanks,

Rob
 
A year later

AirVenture 2014 i bought two earthX 36d's and installed them in my 8. A year later I am completely satisfied.

I replaced a PC680 and a smaller 9 amphour standby battery. I had a contactor fail one time and the brain in the earthX shut it off as advertised. Went through the reset procedure and in a couple hours back to good as new.

I installed a temp monitor between the batteries for added peace of mind.

The cranking power is notably better than the 680. I think I could taxi on just the starter...

Just another data point.
 
Quick question for everyone here.

I was also at the show and saw a few lithium companies, but I wanted to find out some things about them first.

Biggest question for me is where the battery is built. I have purchased lithium batteries in the past, and for the most part they've been built in China or Korea - and those didn't do well. I've come across some companies that put "Made in the USA" but it was really made in China despite that claim, they only put stickers on it or some other nonsense.

I can't find a definite street address, just a PO Box from them, and the only address I did find was for someone's house.

Can anyone help me to verify these guys so I can feel confident about them over other companies? I'm looking around, would like to feel safe about losing that weight.

Thanks!

According to their web site at least:

"We engineer and assemble all our batteries in the U.S.A."

This likely means that components come from all over the place, possibly including China, other parts of Asia, etc ... but this is almost always true of anything you buy, even when it says "Made in the USA".
 
From their "Contact Us" page of their website:
EarthX, Inc., P.O. 767, Windsor, CO, 80550

You also might want to read some of these posts that discuss EarthX and these batteries:
http://www.vansairforce.com/community/search.php?searchid=24650979

Kathy frequently posts on this forum so you might want to ask her directly any questions you may have. Here is a thread she started a couple of months ago:
http://www.vansairforce.com/community/showthread.php?t=125836&highlight=earthX

The answers are out there.

Live Long and Prosper!
 
Where are they built?

From their "Contact Us" page of their website:
EarthX, Inc., P.O. 767, Windsor, CO, 80550

You also might want to read some of these posts that discuss EarthX and these batteries:
http://www.vansairforce.com/community/search.php?searchid=24650979

Kathy frequently posts on this forum so you might want to ask her directly any questions you may have. Here is a thread she started a couple of months ago:
http://www.vansairforce.com/community/showthread.php?t=125836&highlight=earthX

The answers are out there.

Live Long and Prosper!

I would be happy to answer the questions here. EarthX's commercial warehouse where the batteries are built is 1111 Diamond Valley Parkway, Unit 101, Windsor, CO 80550. We do not post this address publically as it is not a retail front and we do not "sell" from this location nor do we receive any type correspondence here. This is a manufacturing site only.

EarthX does qualify, based on the USA regulations set forth by the federal government to have the USA flag and MADE IN AMERICA all over our packaging, advertisements, etc. but we do have to source one of the components outside of the USA and didn't want to mislead anyone as very few people know the legal definition of being able to say "MADE IN THE USA". Many consumers believe if you say MADE IN THE USA, 100% of the components come from the USA which is not true. This is why we choose to say engineered and assembled in the USA.

We do try to have most of the components sourced directly from Colorado as this is the home state. EarthX actually manufacturers the BMS boards on site and own the machine to do this.

One of the first things you do when a business is started is deciding what type of entity the company will be and EarthX is a corporation. The paperwork was filed before a commercial site was secured and does reflect an address of a residence vs. the commercial site. As this was over 6 years ago, this is something we should update. Thanks for pointing this out.

Any other questions, please don't hesitate to contact us.

Kathy
 
We decided to bite the bullet and upgrade our portly 6 with a EarthX. I felt the safeguards EarthX uses would provide the safety factor we wanted. We attempted the battery install today. Sadly we encountered the same width issue others have reported. The specs list the battery as .1 inches wider then the PC680. Visually with the two batteries side by side it appeared to be between 3/16 and a quarter inch wider. We could not make it fit. We will have to fabricate a new spacer assembly in our battery box. If you have a tight battery box in your aircraft it's not going to be a drop in. I am somewhat surprised EarthX did not keep the battery the same width.
George
 
Fitment of the ETX680

We decided to bite the bullet and upgrade our portly 6 with a EarthX. I felt the safeguards EarthX uses would provide the safety factor we wanted. We attempted the battery install today. Sadly we encountered the same width issue others have reported. The specs list the battery as .1 inches wider then the PC680. Visually with the two batteries side by side it appeared to be between 3/16 and a quarter inch wider. We could not make it fit. We will have to fabricate a new spacer assembly in our battery box. If you have a tight battery box in your aircraft it's not going to be a drop in. I am somewhat surprised EarthX did not keep the battery the same width.
George

Dear George,


First off, thank you for your purchase. And we are sorry for the inconvenience of having to fabricate a new spacer assembly and we wish that our battery could fit into 100% of every aftermarket battery box out there but this is one of the boxes we don't easily fit into. We do list on the experimental aircraft page "The ETX680 and the ETX900 will fit into most of your existing PC680 Odyssey hardware battery boxes (there are many aftermarket suppliers and it may not be exact, if you have a 4 sided fire wall forward kit, this will not work with the ETX680 or ETX900) but with many more features and a lot less weight!!"

The battery box you have only measures 2.9" in width, and it a very tight fit for the PC680 as well. The shape of a lead acid battery is also different due to the plastic molding process. If you measure the PC680 is will measure at 3.11" on the top but smaller on the bottom as it is a wedge or cup shape in order to pop the molding out of the molding case. The EarthX battery is symmetrical all the way down.

It was not possible to make our case thinner due to the width of the cells. And again, had we been able to make the case the thinnest part of the PC680, it would then have been too thin at the top due to the difference in shape.

Most reports we get do not have any issues with the install UNLESS it is with the 4 sided solid battery box. We have had about 5 people at this point say it was an issue and what they did is put WD40 on the case and installed it on a warm day when the battery box flexed. Or....do as you are suggesting and modifying the box.

Again, sorry for the additional work needed to install the battery and please continue to post your results and experiences with the install.

Kathy
 
Cell quality

I am more concerned about cell quality
I found many cells that made in unknown places
that dont correspond to datasheet.
1) can you share make and part number of cells used and country of manufacturing ?
2) how does it perform when installed FFWD where temperature exceeding 140F ???
How higher temperatures affect performance
 
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We decided to bite the bullet and upgrade our portly 6 with a EarthX. I felt the safeguards EarthX uses would provide the safety factor we wanted. We attempted the battery install today. Sadly we encountered the same width issue others have reported. The specs list the battery as .1 inches wider then the PC680. Visually with the two batteries side by side it appeared to be between 3/16 and a quarter inch wider. We could not make it fit. We will have to fabricate a new spacer assembly in our battery box. If you have a tight battery box in your aircraft it's not going to be a drop in. I am somewhat surprised EarthX did not keep the battery the same width.
George

George, which Earth X model did you order? I would like to get a look at your battery box before you recowl it. Will try to get over there today to have a look.
 
According to their web site at least:

"We engineer and assemble all our batteries in the U.S.A."

This likely means that components come from all over the place, possibly including China, other parts of Asia, etc ... but this is almost always true of anything you buy, even when it says "Made in the USA".

The vast majority of lithium battery cells are manufactured in Asia... at least until Telsa gets their gigafactory up and running.
 
cell quality

The cell quality is an excellent question! The cells we use are custom made exclusively for EarthX and are based on the engineering design and spec's from EarthX. We have spent years cultivating consistent quality cells and have hundreds of thousands of cells out in the market place. We also visit the factory and test every single cell before production to make sure they meet or exceed the requirements.

We also have the battery management system that also protects the cells and will detect if there is a cell problem over time or due to abuse.

There is a reason why EarthX currently has 13 OEM's (and that number is rising). These are completely independent engineering departments that have tested and approved the EarthX brand of batteries in their factory built planes/helicopters or kit planes. There is also a reason why Rotax engines copied verbatim from the EarthX website what is required to be an approved lithium battery for use with their product. Our mission was never to be the cheapest lithium battery on the market, our mission was to have the highest quality and performance lithium battery on the market.

As with all products, there will be variances in the quality and there are companies out there that source the cheapest cells they can buy and put them in an unprotected plastic case. That is not comparing apples to apples and the entire lithium battery market takes a knock when this happens.

Kathy
 
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George, which Earth X model did you order? I would like to get a look at your battery box before you recowl it. Will try to get over there today to have a look.

Bill we ordered the 680. Our box is between the rudder pedals not on the firewall. We are taking it over to van in the morning to work on a couple of items.
George
 
How about Temperature?

2) how does it perform when installed FFWD where temperature exceeding 140F ???
How higher temperatures affect performance
 
2) how does it perform when installed FFWD where temperature exceeding 140F ???
How higher temperatures affect performance

I worked with Widget over a year ago to install TWO units (primary and "backup" or "AUX") on his RV8 firewall (engine side).

We instrumented them with a temperature probe and monitored the temps.
We set thresholds so he would have a warning if there was a HIGH TEMP.

All has worked JUST FINE over the year. NO problems. I don't have the actual temperatures handy but I am sure that Widget can dig some up from his logs at some point.

I have obtained from EarthX one ETX900, one ETX680 and two EXT18B's.
The ETX900 will be tested on a slightly higher compression engine.
The ETX680 will be tested on a stock O-360 engine.
The EXT18B's will be used as AUX batteries.
- Protecting EFIS'es on cranking and
- Backup to the backup if rest of electrical system goes dead

I will be doing further testing in an RV6 and an RV8. Both have multiple EFIS screens (3 GRT based units each ... )
- 1 HXR + 2 MINIs
- 3 SX's

and an "auxiliary" bus of sorts.

The goal is to get data that can be shared regarding real drain time in real installations, along with *case* temperature data.

The installation has NOT begun yet as I still need to get some a software update for the instrumentation and I am making other mods on one of the planes.

The battery "boxes" are custom on the RV6 and the standard *BIG TRAY* on the RV8 so I should have little mounting problems.

I do have the Odyssey steel box and the units don't fit well in that. I was able to force one in but had a bit of concern about getting it out. Kathy is aware of this and has discussed the limitations that they had.

The EarthX battery box/tray is very lightweight. The only suggestion that I have made so far on that is to extend the length of the "ears" and potentially "pre-drill" mounting holes that would be consistent with the angle that is used on the Van's (Odyssey) boxes.

Stay tuned .....

James
 
I worked with Widget over a year ago to install TWO units (primary and "backup" or "AUX") on his RV8 firewall (engine side).

We instrumented them with a temperature probe and monitored the temps.
We set thresholds so he would have a warning if there was a HIGH TEMP.

All has worked JUST FINE over the year. NO problems. I don't have the actual temperatures handy but I am sure that Widget can dig some up from his logs at some point.

Stay tuned .....

James

I mounted a temp bulb between my two EarthX batteries and wired it into my GRT EIS using the coolant temp circuit. My batteries are on the firewall on the right sde of the engne compartment.

I have never seen the temp between the batteries higher than 134 degrees F. and that is including during shows on very hot summer days. At altitude cruising along I see temps of about 100 degrees F. And with OAT's in the 50?s it's usually about 85 between the batteries.

I am using 36d for my backup, or STBY battery to power ignitions, GRT HXr and dual Mini's. Also, I have my Comm panel, a Garmin GTR200 Comm, GRT GPS and autopilot.

I have left the STBY battery on powering the above equipment for 2 hours and still showed a voltage of 13.1.

Needless to say, if I lose an alternator or the main Batt, i definitely will not be in the air for two hours.

Not a scientific test, but I'm comfortable with my numbers.
 
Any one with negative?????

They are rather expensive as compared to a much cheaper battery that you may find at the local battery store.

If you have a "nose light" RV like my RV6 then the lack of weight may not be desirable.

When the voltage falls below a certain threshold the battery management system shuts it off. So it MIGHT be possible for an Earth battery with the SAME capacity as a PC680 to turn off your EFIS sooner than a traditional battery. For example if your EFIS works down to 10 volts and the EarthX turns off sooner you MAY have given up a few minutes of run time.

I spoke with Kathy about this this morning and this one of the items I plan to get empirical data about.

DISCLOSURE; EarthX supplied me with the batteries I mentioned for testing. I am free to speak the good , the bad, and the ugly as I see fit. I will though validate any findings with them. The batteries we put in Widget's plane were BOTH PURCHASED by Widget.

James
 
We installed a EarthX 680 in a RV6 today. As I mentioned in another thread we had to modify the battery box because the EarthX was about 3/16 of a inch wider. There was a second small install glitch as the battery posts have less clearance from the raised top then a Pc680. This required grinding one side of the battery cable ring eyes down about ⅛ of a inch. Ours were big so perhaps a non issue for most.
We have a 360 with a lightweight prop and 10 to 1 Pistons. It spun the engine noticeably quicker then the PC680. We also did a avionics update taking about one hour on the battery. There was no detectably difference on start after the update. We did kill unneeded avionics during the update. There is one noticeable difference from a conventional battery. After start the battery can take up to a 60 amp charge rate. We are seeing 58 to 63 amps after start. This lasts for less then two minutes and amps drop to the normal range. EarthX says this is normal since the battery can intake a lot of amps fast. If you have less then a 60 amp breaker on the alternator this could be a problem. We have a 70.
George
 
<<STUFF DELETED>>

There is one noticeable difference from a conventional battery. After start the battery can take up to a 60 amp charge rate. We are seeing 58 to 63 amps after start. This lasts for less then two minutes and amps drop to the normal range. EarthX says this is normal since the battery can intake a lot of amps fast. If you have less then a 60 amp breaker on the alternator this could be a problem. We have a 70.
George

I have seen my PC680 take between 55 and 60 amps for a short while as well.
This is after I had used it for quite a while doing something with the avionics and had just enough juice left to crank the engine.

So ditto on making the fuse/breaker/whatever some amount greater (say 20%) than the alternator is capable of delivering.

James
 
EarthX battery Fault monitoring and how to wire into GRT EFIS HX?

Guys,
Can you share how you wired in the EarthX (ETX680) battery fault monitor into your Grand Rapids Technology EFIS? I have the HX displays.

How did you wire this in and and how did you configure it in the Setup Menu software?

Per the ETX Manual:
Fault Monitoring Installation (ETX Hundred Series)
The ETX Hundred Series batteries have a discrete output that can be connected to many aircraft Electronic Flight Instrument System (EFIS) electronics or to a remote mounted LED. The diagrams below detail the required connections for both type installations. The discrete output for external fault monitoring is a single wire with 1⁄4? quick connect terminal. The 1⁄4? quick connect terminal is an insulated ?female? type and should be compatible with most other manufacturers insulated male 1⁄4? quick connect terminals. The discrete output can be used with an independent DC source or your ETX?s battery voltage from 5-15VDC. If an independent DC source is used (i.e. from EFIS), the DC source negative must be referenced to the battery negative.
To test the internal LED and or external LED, touch the fault monitoring wire to battery negative.

--------

Thanks,
Howard
 
2) how does it perform when installed FFWD where temperature exceeding 140F ???
How higher temperatures affect performance

I asked Kathy.

She said it was ok to post it here.

Subject
Battery Temperature
Enquiry
I have been following the lithium battery developments for a long time and am interested in using one for my Experimental airplane.

There are several pictures floating around showing that one of your batteries is interchangeable with an odyssey PC680 battery which is typically mounted on the engine side of the firewall on may experimental airplanes including my own.

Your specifications show that the maximum operating temperature is 140 deg F.

I am quite certain that in many of these installations including my own, the actual temperature at the battery exceeds this temperature on a really hot day after the engine is shut down and there is no cooling air flowing through the engine bay.





Subject: RE: New submission from Contact Form

Dear Joel,

Thank you for the question. The operating temperature for a lead acid is 113 degrees Fahrenheit and the ETX680 is 140 degrees Fahrenheit but this is an operating temperature, do not attempt to charge the battery above this temperature. The storage temperature is 158 degree Fahreheit.

We do have a manual online that addresses these questions as well for your review.
http://earthxmotorsports.com/wp-content/uploads/2015/07/ETX_Manual_111017_K.pdf


Please let me know if you have further questions.


Sincerely,
Kathy Nicoson
EarthX Lithium Batteries


Subject: RE: New submission from Contact Form

Dear Kathy,

Thank you for the response! I have read the manual several times and I feel my question is still not answered unless I understand something wrong.

Maybe I should be educated on the definition of operating and charging?

Can we consider the following example?

The battery is installed in a location that gets above 140 deg F during operation. I understand that to be considered storage. However, in the same location installed on an airplane a pilot may opt to land for 10 minutes, fill the tanks with fuel, then start the engine. Let?s assume he doesn?t know how to get the fuel/air mixture correct on the first and second start attempts and finally after desperation gets his engine started but he used 70% of his battery charge in the process.

Now we have a battery installed in a location that is over 140 deg F due to the engine just being shut down from the previous operation AND the battery will automatically be making the alternator charge it. Would this not be considered CHARGING or do we still call this operating?

Please enlighten my weak mind.

Thanks Joel


Subject: RE: New submission from Contact Form

Dear Joel,

I had one of our engineers look this over and this is what he said:

?Operation? would be charging or discharging (current in or current out).

The main point is our battery should not be used in applications where the ?battery? temperature is over 140 deg F during charging or discharging. In your example below, would the battery temp (more specifically the cells inside the battery case) actually exceed 140 deg F in 10 minute ? most likely not. Are brief periods of time above 140 deg F ok ?. Sure, for 10-15 minutes.

But if you have measured your engine compartment and it exceeds 140 deg F for long periods of time, then it can?t be used in the engine compartment.?


Let us know if you need any further questions.


Sincerely,
Kathy Nicoson
EarthX Lithium Batteries
Global Sales Director



Subject: RE: New submission from Contact Form

Thanks Kathy!

Good information! Care if I share it on the Vans Airforce forum?


Subject: RE: New submission from Contact Form

Hi Joel,

Thank you for asking and of course you can. I already know I am going to receive a ton of responses asking more questions about this, which is fine, but the lead acid battery, which pilots have been using for decades, have a high temperature reading of only 113 deg F compared to the EarthX at 140 deg F just as a side note. The response from a lead acid company would have that if you measure your engine compartment above 113 def F, do not use it there.

It is a bit more complex in that it is the temperature of the inside of the battery or the cells in reality that should not exceed the 113 deg of a lead acid battery and 140 deg of a lithium battery. Much harder to measure. We have had a few fly with temperature monitors on the batteries and we have not had a report back of temperatures actually reaching this temperature but I am sure there are people who can.


Sincerely,
Kathy Nicoson
EarthX Lithium Batteries
Global Sales Director



Many don?t realize that the lead acid battery is only rated to 113 deg F as this information isn?t easily available whereas we post it. The temperature ratings are far better with a lithium battery than a lead acid, as the chemistry is very different so it is great to ask and post the questions.

Have a fantastic Friday!


Sincerely,
Kathy Nicoson
EarthX Lithium Batteries
Global Sales Director
 
So, here's my question regarding the EarthX or other LiFePO4 batteries. I fly a -9A and the current 680 battery is mounted on the firewall. There are 2 1/2" hoses bringing cool ram air from the baffles to the battery. I have hoses going to the starter, alternator as well, all are sealed at the baffles and work nicely. Does anyone have any data on the temperature at the firewall where the battery would mount? I really like the EarthX and am fast approaching replacement time figuring I would do that during my January annual. Thoughts?
Thanks,
Dave
 
Not really an answer. I monitor the temperature of the air exiting the bottom of the cowl. It is usually between 150-170 F but can reach 200 F for a brief time during climb. The battery may be in a slightly cooler environment than where the the probe is due to the proximity of the exhaust pipes, not sure how much. After shut down (and the engine monitor turned off so no data available), the whole cowl interior temp will go up for a brief time as there is lots of heat and pretty much zero airflow. I don't know if this brief temp increase will be hard on the battery but I doubt it. I am currently using a Shorai 18Ah battery at less than 3 pounds. 35 hours so far and no ill effects.

Bevan
 
Not really an answer. I monitor the temperature of the air exiting the bottom of the cowl. It is usually between 150-170 F but can reach 200 F for a brief time during climb. The battery may be in a slightly cooler environment than where the the probe is due to the proximity of the exhaust pipes, not sure how much. After shut down (and the engine monitor turned off so no data available), the whole cowl interior temp will go up for a brief time as there is lots of heat and pretty much zero airflow. I don't know if this brief temp increase will be hard on the battery but I doubt it. I am currently using a Shorai 18Ah battery at less than 3 pounds. 35 hours so far and no ill effects.

Bevan

We put DUAL EarthX batteries (forget the exact model number, but the "more than a PC680" version) in Widget's plane (RV8) over a year ago.. We installed temperature probes at the batteries.

Over a year of operation and no termperature issues.

Widget may have actual data and when he sees this next, hopefully he will respond.
 
....I thought this thread a good place to share some information on our experiences with batteries, and what we are currently using. We, as most people originally started with the Odyssey PC680 batteries. After some alternator issues we thought it prudent to move up to a battery with more reserve power in case of another alternator failure. We elected to install an Odyssey PC-925 battery and were for the most part satisfied with it as it cranked the engine pretty well and had the extra reserve power. On our 9-A the battery is located low on the firewall, pilot side. The heat in flight was fine but the radiated heat from the exhaust has always been an issue and had distorted the case on a couple on batteries. The other issue with this larger battery was the weight at over 27lb. When researching what was available we started looking at the lithium iron batteries and decided to give them a go. We chose the Shorai Lithium Battery LFX36A3-BS12. This is a case of overkill and as we later found out we could have gotten by with half this size and half the expense as well. This little sub 5 lb battery cranks the engine better than the 27 plus lb battery we took out. It holds a charge, unattended for extended periods of time as well. I must admit we were all very skeptical at the beginning of our tests and couldn't imagine this tiny little thing doing the job it does. We now have over 450 hrs on this battery and it has performed flawlessly in every respect. I have monitored the individual cells to see if they would ever achieve an unbalanced condition, needing to be balanced with the special charger. They have not! We were so impressed with the performance, we decided to become a dealer for this product and have many out there in service. Every report back to us is overwhelmingly positive and we have not even one unhappy with their purchase. We are not posting this to sell batteries, but rather to inform others of our experience with the product. These lithium batteries have a wide price variation from brand to brand. It appears they are all made in China and come from the same town or region, and all have wild claims of performance, safety, warranty, etc. One needs to evaluate all this carefully to make their own decision as to what is real or perceived. I hope this information will help others with their battery decisions and help relieve some of the battery anxiety connected with the lithium iron batteries. Thanks, Allan...:D
 
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So, here's my question regarding the EarthX or other LiFePO4 batteries. I fly a -9A and the current 680 battery is mounted on the firewall. There are 2 1/2" hoses bringing cool ram air from the baffles to the battery. I have hoses going to the starter, alternator as well, all are sealed at the baffles and work nicely. Does anyone have any data on the temperature at the firewall where the battery would mount? I really like the EarthX and am fast approaching replacement time figuring I would do that during my January annual. Thoughts?
Thanks,
Dave


I have 2 EarthX 36D batteries on my firewall with a temp monitor. They are on the lower right side where most batteries on 8's are mounted. IO370 with 4 into 4 exhaust, horizontal sump, no snout on cowling.

My temps between the batteries are.

OAT 50 BATT 83
OAT 70 BATT 93
OAT 80 BATT 100-110
OAT 90 BATT 120-130

Never seen hotter that 135 between that BATT's even during airshow with temps in the high 90's and the engine oil temp 210, low airflow.

Of course this is just my set up.

Hope this helps.
 
Battery Temps

Originally Posted by vluvelin
2) how does it perform when installed FFWD where temperature exceeding 140F ???
How higher temperatures affect performance

In my Cummins Diesel truck, the batteries are insulated with a 1/4 inch thick blanket of sorts. This could easily be done on the firewall of the plane to guard against the shut-down, refuel-heat up,-restart scenario. Would help a lot on en-route temperature protection too. The battery box could be insulated in many ways. Just a thought.
 
Originally Posted by vluvelin
2) how does it perform when installed FFWD where temperature exceeding 140F ???
How higher temperatures affect performance

In my Cummins Diesel truck, the batteries are insulated with a 1/4 inch thick blanket of sorts. This could easily be done on the firewall of the plane to guard against the shut-down, refuel-heat up,-restart scenario. Would help a lot on en-route temperature protection too. The battery box could be insulated in many ways. Just a thought.

Just my opinion like, but I have actual temp data to work with and I have never seen over 135 degrees on the firewall 100 degree day's working the plane really hard down low from 0 to 200 kts.

sure seems like a lot of problem solving for a problem that doesn't exist.
 
....<<<SNIP>>> We chose the Shorai Lithium Battery LFX36A3-BS12. This is a case of overkill and as we later found out we could have gotten by with half this size and half the expense as well. This little sub 5 lb battery cranks the engine better than the 27 plus lb battery we took out.

<<<SNIP>>>

These lithium batteries have a wide price variation from brand to brand. It appears they are all made in China and come from the same town or region, and all have wild claims of performance, safety, warranty, etc. One needs to evaluate all this carefully to make their own decision as to what is real or perceived. I hope this information will help others with their battery decisions and help relieve some of the battery anxiety connected with the lithium iron batteries. Thanks, Allan...:D


I think that if all one wants is cranking then a smaller battery may be just fine. But with the increasing number of totally "electrically dependent" planes out there, the higher capacity choice may be a good decision even though there is some more cost. It is for this reason, over a year ago, when Widget and I discussed what he was going to use he ended up choosing (dual actually) 36 Ahr (at least) batteries of the "lithium variety".

Second point, regarding "made in America" (or elsewhere), according to the EarthX website:

All our products are engineered in the USA
We use American battery technology, the most advanced lithium battery technology in the world
Our batteries are assembled, engineered and designed in the USA using US and foreign components
.

Not a debate of Shorai v EarthX, just wanted to put that out there for those who care as I seem to recall that someone had brought this up before.

DISCLAIMER: I assisted with an EarthX install (Widget's) over a year ago.
 
Small earthx

I have a io-360 200hp with thick and short cables. What is the smallest size earthx that will start the engine?
 
I have a io-360 200hp with thick and short cables. What is the smallest size earthx that will start the engine?

I would try the ETX680. I *think* that is the number of the one they have as a potential "replacement" for the PC680.

When we did Widget's that model number did not exist.

I am sure they will correct me if I am wrong. That is what I will be installing to turn a an O-360 (180 HP) as soon as I can get a few other projects cleared up. :)

James
 
I would try the ETX680. I *think* that is the number of the one they have as a potential "replacement" for the PC680.

When we did Widget's that model number did not exist.

I am sure they will correct me if I am wrong. That is what I will be installing to turn a an O-360 (180 HP) as soon as I can get a few other projects cleared up. :)

James

No, wait, you must use the battery matched to your alternator output. If you have the standard 60 amp alternator, then the ETX680 is the right battery because it's designed to accept up to 60 amps of charge. I installed PlanePower's 70 amp alternator: Thus, I bought the ETX900 which accepts up to 80 amps of charge.

This is vital, because LiFePO4 batteries take the alternator's MAXIMUM charge output after engine start and alternator activation. After about 10 or 20 seconds, the charge drops down to current load. Imagine trying to force 70 amps charge into the 60 amp ETX680...not good.

While you're at it, recheck the gauge cable you have running from the alternator to the battery. It'll get that max amperage workout every single time you start the engine and charge.

I love my EarthX ETX900. Like Scott Farnsworth said, it turns the prop sp powerfully I swear I could taxi the aircraft on starter power alone. :cool:
 
No, wait, you must use the battery matched to your alternator output. If you have the standard 60 amp alternator, then the ETX680 is the right battery because it's designed to accept up to 60 amps of charge. I installed PlanePower's 70 amp alternator: Thus, I bought the ETX900 which accepts up to 80 amps of charge.

This is vital, because LiFePO4 batteries take the alternator's MAXIMUM charge output after engine start and alternator activation. After about 10 or 20 seconds, the charge drops down to current load. Imagine trying to force 70 amps charge into the 60 amp ETX680...not good.

While you're at it, recheck the gauge cable you have running from the alternator to the battery. It'll get that max amperage workout every single time you start the engine and charge.

I love my EarthX ETX900. Like Scott Farnsworth said, it turns the prop sp powerfully I swear I could taxi the aircraft on starter power alone. :cool:

SO TRUE!!! What he said!! :)

I (probably incorrectly) assumed that you were running a 55-60A alternator.

James
 
Alternator

I have a plane power alternator 30 amp. I think that my small avionics bus is about 5 amps. So that is 25 amp of charge. I am looking at the etx18 or etx24. This is a very light airplane.
 
PC 925 replacement?

Which would be the right one to replace the PC925 with a 60 amp B&C alternator. It looks like it would take the ETX 1200 to not lose any cranking amps or standby AH's, but it looks a little pricey. I would be really nice to lose the weight of the PC925 from the aft end of the RV10.
Vic
 
Which EarthX battery?

Which would be the right one to replace the PC925 with a 60 amp B&C alternator. It looks like it would take the ETX 1200 to not lose any cranking amps or standby AH's, but it looks a little pricey. I would be really nice to lose the weight of the PC925 from the aft end of the RV10.
Vic

Hi Vic,

Thank you for the question. In matching up a lead acid to a lithium battery, the amount of amperage the alternator puts out is very important to match up and if this was the only requirement, any of the aircraft batteries would work in your plane that has the 60 amp alternator but that is only one piece of the equation.

Next you need to match up the amount of amperage your battery has in the event your alternator fails, which is the most critical, and you are on battery power only. Based on this, the 1H 1C rate for the PC925 is 21.9ah, the ETX680 has 12.4ah, the ETX900 has 16ah and the ETX1200 has 24.8ah. Based on this, the ETX1200 is most suitable.

The last part of the equation is the cranking power. The PC925 has 330CCA, the ETX680 has 320CCA, the ETX900 has 400 CCA and the ETX1200 has 600CCA.

The weight savings is amazing on all of them. The PC925 weighs 26 pounds. If you choose the ETX680, you save 22 pounds; the ETX900 you save 21 pounds and if you choose the ETX1200, you save 18 pounds. The cost of the EarthX battery is definitely more than the PC925 which price is around $135. The difference is cost from the ETX680 is $244 more or $11/pound to reduce that amount of weight. The ETX900 is almost $15/pound to reduce that amount of weight and the ETX1200 is $33/pound to reduce that amount of weight. There is no cheaper way to reduce the weight on your plane and the weight loss does add up in fuel savings and increased horse power as well as a side benefit.

Hope that answers your question!

Fly Lightly,
Kathy
 
Thanks.

I agree with all of your points. Let me ask it this way... given an aircraft with 2 alternators and a TCW backup battery for the EFIS, wouldn't the 900 be a viable alternative without losing anything other than the AH capacity? Cranking capacity should be better, correct?

Vic
 
I agree with all of your points. Let me ask it this way... given an aircraft with 2 alternators and a TCW backup battery for the EFIS, wouldn't the 900 be a viable alternative without losing anything other than the AH capacity? Cranking capacity should be better, correct?

Vic

Yes, as long as you know you are getting a battery with less usable amp hours than the PC925, all the other parts of the equation line up. You are very welcome to call us at (970) 674-8884 if you have any questions as we are here to help support you in making a decision you are comfortable with!

Fly Lightly,
Kathy
 
smallest earthx

what is the smallest just for starting? I don't care if my alternator quits and I lose power. I have a 30 amp alternator. I was looking at the 18 and 24 model.
 
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