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LiFePo battery?

Moderators, can you please cancel Kathy's account for posting non RV related material?

Kidding! We welcome all sorts of aircraft builders here. VAF is so huge, many builders of other aircraft frequent it to learn about
various non RV specific aspects of kit construction. Even glas aircraft builders. :)

One thing I noticed in the 2nd photo above is that there is no hold down on the battery. Maybe it just wasn't installed when the photo was taken.
 
Ha! your funny! I have the picture with the hold down but it covered up our beautiful battery top so I didn't use it. Maybe I shouldn't call our batteries beautiful as mostly men are using them and they might think that is a bit too feminine of description.....how about if covered our heavy duty, very strong, as powerful as a tank, battery.

Kathy
 
LOL! I think most men can consider nice examples of machinery/electronics 'beautiful'. I was thinking just that about my panel last night when I installed all my components into it. :)
 
grayforge said:
Kidding! We welcome all sorts of aircraft builders here. VAF is so huge, many builders of other aircraft frequent it to learn about
various non RV specific aspects of kit construction. Even glas aircraft builders. :)
Click to expand...

RVers in general form a community that attracts knowledgeable people and industru representatives, and that inevitably attracts other fliers. I have an airplane that is not aerobatic and cruises at 62 knots, and I'm looking at buying EarthX ETX24D, and I need to determine if their electronic circuitry adds or detracts to their reliability. There's just no other place other than VAF for this kind of thing, because nobody else actually flies with those batteries in any numbers.
 
zaitcev said:
RVers in general form a community that attracts knowledgeable people and industru representatives, and that inevitably attracts other fliers. I have an airplane that is not aerobatic and cruises at 62 knots, and I'm looking at buying EarthX ETX24D, and I need to determine if their electronic circuitry adds or detracts to their reliability. There's just no other place other than VAF for this kind of thing, because nobody else actually flies with those batteries in any numbers.
Click to expand...

Excellent questions and for what it's worth, the EarthX battery has been used and discussed for years now on the Sub Cub forum and the Zenith forum as well and probably other ones too that we are not aware of if you are looking for additional discussions on the reliability and performance of the batteries.

As far as the question, does the circuitry add or detract to the reliability.......all lithium batteries used in equipment have a built in battery management system for protection as it is required to make them operate properly and safely except in the power sport market that is being flooded with Chinese batteries that skipped this safety feature. It would be like Ford putting out a new model of trucks...with no brakes. It is just expected that the product has the needed safety built in but that is not happening in this field at this time and won't until the consumer is educated and aware of the importance of these features and demand it or refuse to buy it before companies will add this as it is expensive and requires a lot of engineering R & D to design the circuitry. We have started to see the marketing terminology change saying "electronics" built in but no qualifying statements of what they means. If the warranty is voided by over charging, over discharging, or not using a balancing charger...I would say the "electronics" they are referring to is perhaps the wires to connect the cells and nothing more.

Your cell phone, lap top, even your cordless drill has this protection built in. If you over charge a lithium, they can over heat and puff. If you over discharge a lithium, ONE TIME, they are destroyed, if you do not balance the charge and discharge of the cells, you are using the least charged cell to operate your vehicle and then they are susceptible to being overcharged or over discharged by the charging system you are using. So the answer to your question is yes, it does add to the reliability of battery.

Kathy
 
SHOW PRICING SPECIAL AT OSHKOSH

We are getting packed up and ready to head to Oshkosh so I wanted to put it out there that we will have a show special if you have been wanting an EarthX battery and been waiting for them to have a sale price. :) You are welcome to call and preorder so you know for sure your battery is waiting for you! You can call at (970) 301-6064 between the hours of 8am - 5pm mountain time. This special will not be on the website, so we have to over ride the pricing directly which is why we need you to call with the order. No sales tax, no shipping fees and discounted pricing to boot! I am really excited about this show!

Kathy
 
Kathy, what is the usable life of these batteries? Since the price point is much higher, it would be good to know how long it is going to last - assuming normal use and maintenance is followed.
 
Design Life of EarthX batteries

CharlieWaffles said:
Kathy, what is the usable life of these batteries? Since the price point is much higher, it would be good to know how long it is going to last - assuming normal use and maintenance is followed.
Click to expand...

The design life of our batteries is 8 years with 4,000 charge cycles. Just to give you a frame of reference, most lead acid batteries have 500 charge cycles and are designed for 3 years life.

Kathy
 
grayforge said:
Hi Kathy,

Regarding the sale price, do you have details? Like is it XX% off?

Thanks!
Russ
Click to expand...

Hi Russ!

It would be a violation of our dealer agreements for me to "advertise" the price but if you call (970) 301-6064, or send me an email to: [email protected] I will gladly tell you. :D

We will also have the Optimate Lithium Battery charger with us for sale as it is designed to work with all the lithium batteries and it also has the built in reset feature for our BMS in the event you over discharge it. It also has a maintaince mode that you can use if you want to leave the battery left on a charger for an extended period of time so it is fully charged when you are ready to use it again. I can tell you the retail price on this is $64.90 but at the show it will be $50, out the door.

Kathy
 
OSHKOSH IS AMAZING!

This is only Thursday night but I wanted to say what an awesome show this is and thank ALL OF YOU that have stopped by to meet us and check out the product in person. And of course, a huge thank you to all of you who have placed your trust and business with us and purchased a battery....or two. :eek:

I am excited to see the Thunderbirds tomorrow!

Kathy
 
Kathy, it was a joy to put a face to your posts!

EarthX's booth is in an area of the hangar where there are some empty booths, but there was always a crowd looking at these lightweight batteries.

Looking forward to receiving my ETX36C. :)

See ya!
Russ
 
There is a good article in this months kit plane on LiPo batteries. Worth reading if your looking at one.
George
 
I'm converting my RV-8 to an (I)O-360 w/ CATTO 3 blade. Weight reduction is a major goal. I'm hoping to move the battery from the back to the firewall and switch from a PC-680 to a LiFePo4. The savings in battery cable weight alone is significant.
It occurs to me that a lighter alternator is also called for, with 20 amps being plenty, given the low specified charge rate for the LiFePo4 type. (Although I see the EarthX Battery aviation link permits a 40 or 60 amp charge rate depending in battery capacity)
 
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sailvi767 said:
There is a good article in this months kit plane on LiPo batteries. Worth reading if your looking at one.
George
Click to expand...

Hi George,

Do you have a link for this article or can you point me in the direction on how to find it? I would be interested to read it myself.

Kathy
 
BACK FROM OSHKOSH

This was an amazing show and the Disneyworld of aircraft ideas, parts, information, and collection of pilots! For those of you who left before Sunday, it absolutely poured at times, wind was in huge gusts, and I would imagine trying to get your airplane off of the grassy field was a huge challenge if you stayed! I hope you all had a great time as I know we did and we thank all of you who stopped by and for the ideas you have given us as far as what you really want! We are looking forward to Sun N Fun and will definitely be at Oshkosh next year!

Kathy
 
We stopped by your booth, and there were folks waiting 3 deep to see/touch/talk.

Since I am not currently in the market for a new battery, I decided to move on, and not add to the delay for other folks.

Sorry I missed the chance to say "Hi"

Glad you were there, and hope the trip was worth it.
 
Mike S said:
We stopped by your booth, and there were folks waiting 3 deep to see/touch/talk.

Since I am not currently in the market for a new battery, I decided to move on, and not add to the delay for other folks.

Sorry I missed the chance to say "Hi"

Glad you were there, and hope the trip was worth it.
Click to expand...

Hi Mike,

Thank you for "trying" to stop by and it was a very BUSY show for us as you saw! I apologize we didn't have a chance to meet in person and I appreciate your consideration of our other booth guest. :D As we plan on being at the other air shows down the line, maybe we will get a chance to meet then. I hope you had a great time in Oshkosh!

Kathy
 
Frequently asked questions we received from Oshkosh

There were some very definite themes to the questions we were asked at the show so I thought I would highlight some here. Matching up a battery takes several things into consideration, you need to match up the CCA's, the capacity (usable amp hours), and the actual physical size.

So that being said, I will respond to the capacity (usable amp hours)question as this is very important and I know several of you were hesitate to ask because you didn't want to appear lacking in knowledge and sent us emails to explain. Please know there is no dumb questions!

The usable amp hours are what you will use IF AND ONLY IF your alternator fails during flight and is not recharging the battery. You then are running your instruments on battery capacity (usable amp hour) only. In the event of this event, you would of course not use any instrumentation that is not necessary and want to find a landing spot. So the PC680 has 12.8 usable amp hours at an 80% depth of discharge (DOD). So if you needed say 6 amp hours to run your avionic equipment, you would have a little over 2.1 hours of power from the PC680, 2 hours from the ETX36 series, and 4 hours from the ETX48.

Kathy
 
Are you going to get TSO certified?

Next BIG question we received was are we going to get TSO certified as many experimental aircraft owners also have certified planes.

We are in the process of looking into this and all that is required and if we are able to "afford" the process in it's entirety.

But this is my question for you....True Blue Lithium batteries have recently became a certified lithium battery and the retail price in in the range of over $2,000 and only is 50% of the weight. Would you pay this?

Kathy
 
Thanks Kathy,

I really appreciate all of the information you have been providing. I was an early adopter of LiFePO4 technology.

While I have had no issues since replacing my PC680 an 18AH battery, I decided - based on your data - to upgrade to something the size of the ETX36.

Sizing has been one of the most discussed topic (outside of safety concerns).
 
I bet you'll find most of the people on VAF would be more interested in a PC680 sized replacement (drop-in) than a TSO'd version. :)

On the capacity subject, I need to get a PC680 so I can do a controlled experiment:
Running my avionics on the PC680, then the ETX36C and note which items go offline at which times on each battery.

I imagine the PC680 will have items dropping off one by one: GRT Mini-B first, then Garmin G3X Touch, etc., while the ETX will have everything drop at once since its electronics will shut everything down at a certain voltage.

Thanks!
Russ
 
Russ - I'm curious as to why you believe the Mini will drop off line before the G3X... On what are you basing this belief?

I've measured the drop-out point of my Mini-X to be just a hair over 9V. Does the G3X run at less than that (checked through measurement rather than a spec sheet)?

The Dynon D100 in our plane never flickers during engine start but I haven't measured it's dropout voltage - it's got to be pretty good.
 
Canadian_JOY said:
Russ - I'm curious as to why you believe the Mini will drop off line before the G3X... On what are you basing this belief?

I've measured the drop-out point of my Mini-X to be just a hair over 9V. Does the G3X run at less than that (checked through measurement rather than a spec sheet)?

The Dynon D100 in our plane never flickers during engine start but I haven't measured it's dropout voltage - it's got to be pretty good.
Click to expand...

This is from testing. While running on a motorcycle battery, with both Mini-B and G3X power on, the Mini B drops into its non-functional mode (display still illuminated, but with an "Input Voltage Too Low" error message). This is at 9.5V, as seen on the VPX page on the G3X Touch.

DSC01269.JPG
 
Thanks for sharing that info, Russ. How low would the G3X go before it gave up the ghost? More importantly, how many extra minutes of run time did the G3X have over the Mini? At that low voltage level I would expect most aircraft batteries would be fading pretty quickly.
 
I didn't do any longevity testing since I was using just an old motorcycle battery. Wouldn't have compared to a fresh PC680.

I'll see if I can get a voltage where the G3X drops offline.
 
EarthX Lithium said:
...But this is my question for you....True Blue Lithium batteries have recently became a certified lithium battery and the retail price in in the range of over $2,000 and only is 50% of the weight. Would you pay this?

Kathy
Click to expand...

For the sake of market research my response is ... no. I wouldn't spend $2k to save that little weight, especially if there is a non-TSO version for much less money that I can use because I was smart enough to go the experimental aviation route:D
 
Kathy,
I discussed the following with your associate at Oshkosh. He was going to check.

I understand that your batteries can operate at a higher temperature ( I believe it was up to 60C or 140F) than the odyssey pc-680.

My question was what temperature can they stand with no damage when the plane is sitting still? I.E., after shut down.

Without measuring, I suspect under cowl temps can easily rise to 170-180F. Will the LiPo battery suffer any damage at these temps (assuming shutdown, no load on battery)?

Thanks,
Tom H.
 
tomhanaway said:
Kathy,
I discussed the following with your associate at Oshkosh. He was going to check.

I understand that your batteries can operate at a higher temperature ( I believe it was up to 60C or 140F) than the odyssey pc-680.

My question was what temperature can they stand with no damage when the plane is sitting still? I.E., after shut down.

Without measuring, I suspect under cowl temps can easily rise to 170-180F. Will the LiPo battery suffer any damage at these temps (assuming shutdown, no load on battery)?

Thanks,
Tom H.
Click to expand...

Hi Tom,

We have not forgot about you and this question and will let you know as soon as we have an answer. Sorry for the delay but engineer's do not take these important questions lightly and want to have a correct answer for you. Please be patient.

Kathy
 
Tonight, I did some experimenting with voltages and what falls off when...

Everything's running at 12V+, of course.
At 10 volts, the Mini-B drops into Low Voltage Error Mode
At 8 volts, the G3X Touch AHRS drops off
At 7 volts, the G3X Touch display starts failing

Here's a sequence of images demonstrating this.

Everything Running:
DSC01714.JPG


Mini B dropped offline:
DSC01715.JPG


G3X AHRS about to fail:
DSC01716.JPG


Lowest voltage where the G3X display works:
DSC01717.JPG
 
Mark C. Provided this install details for the EarthX ETX48E in his RV-10

"I was able to get the battery installed in my RV10 today. There was only a little bit of work to do to get it to fit. Here are the notes and links to pictures."
http://tinyurl.com/nadnssd



1) The width of the ETX48E is an exact fit for the width of the Odyssey
PC925 - so anyone that is using that battery (most all RV10s), the existing angle piece in the battery tray works perfect to hold the aft end of the ETX48E.
2) The depth of the ETX48E is about 1-5/8" thinner than the PC925 (typically installed on its side). I used a piece of UMHD with some lightening holes to reduce weight to take up the extra room in the tray behind the ETX48E battery.
3) The stock battery tie-down lands on top of the battery but is off the back of the center built up area (where the EarthX label on top is). To fix this, I made a 6"x3/8" piece of UMHD and epoxied it to the top of the battery. The tie-down bar then fell equally on the UMHD block and the exposed battery top.
4) The existing wiring runs from the Master Relay and the Ground Wire were all a perfect length to reach the ETX48E when using the Terminal Adapters to move the attach points to the front of the battery from the top.
5) The screws to attach the Terminal Adapters were outfitted with a lock washer and a flat washer to secure the screws in place. The same thing was done to secure the battery cable lugs to the terminal adapters.
6) A MS25171-3S insulting rubber boot was installed over the top of the POSITIVE side of the battery terminal adapter to protect the exposed terminal. It also protects it from the nearby battery tie-down bar.
7) The change out took about 2 hours including fabricating the new spacers.
8) The battery worked great and it seems like the starter has a little more oomph than the Odyssey battery.


Thank you all who take the time to help out fellow builders and share with us your experiences!

Kathy
 
EarthX wants your thoughts on this battery holder

We met a metal fabricator at the OSHKOSH show and he presented us with this adjustable battery tray idea made out of aluminum and weighs less than 2 pounds. This is a prototype but we thought we would ask all of you for your thoughts or opinions.

23r0p76.jpg
[/IMG]
 
That looks pretty cool Kathy.

Thoughts:
  1. "Under 2lbs" sounds a bit heavy. I would hope for under a pound.
  2. The straps don't give me as good a feeling of security as bolts/tie-down
  3. Aluminum will be more likely to stress crack than steel.

But it does hold promise. :)
 
Thanks for the quick response! Another response received is that Nylon is not very flame resistant and in the event of a fire, having a strap that would not melt off and set the battery "free" is a better idea. Or even better yet, an aluminum case that encloses the battery all together in the event of a fire so it is protected from flames is the best solution. I agree! The width is always the same, the height and length can differ depending on which model is used.

Kathy
 
That looks good.

I personally wouldn't have a problem with the nylon straps, particularly for a lightweight lithium battery. I've got a pair of nylon straps that hold the battery in place in my 4WD and it doesn't move an inch and the battery is a heck of a lot bigger & heavier than the Shorai I've got in the -9.
 
Thank you so much for your input and I am sharing everyone's ideas with the metal fabricator as the ideas have been great!

Kathy
 
Again, that has no place on the firewall of an airplane. Surely for comedic relief only.
 
Personally, I'd prefer a full enclosure of stainless steel, with a vent opening that can be ducted outside the aircraft. The material can be the same as the firewall.

I have no idea how to design the various openings for cables or access, though.

Dave
 
...except for when it's on fire!

FYI, Kathy, the firewall is made of .018" stainless steel. It would be nice to have the battery completely enclosed (as improbable as a fire might be).

For comparison purposes, here's a battery box for the Odyssey series and also a certified aircraft battery box.

HD680-Hold-Down-for-PC680-Odyssey-Drycell-AGM-Battery.jpg


bogert-black-powder-coat-finish-battery-box.jpg


David
 
When a lithium battery overheats it can release fire, smoke, flammable gasses, and toxic chemicals. The LiFePO4 battery chemistry is more stable than others, but there still exists the possibility of all of these conditions. A battery management system (BMS) can help to further minimize the probability of a failure, but still some risk remains.

Having a fireproof stainless steel enclosure vented outside the aircraft would provide a degree of containment in event of a battery failure.

There are lots of opinions out there on whether or not using one of these batteries in your aircraft is a good idea. Up to the builder to make the call.

David
 
Kathy, as I mentioned on the RV-10 thread, the audience is very polarized. Some believe the risk is worth the benefit. Others have made up their mind that LiFePO4 batteries will cause spontaneous death if used in an aircraft and are not shy about interjecting their opinion, even when not asked. But it is an Interweb BB.

I recommend you seek the opinions of people open to the concept of using this product who have actual and practical knowledge of materials, risk management, manufacturing methods, etc. There's a lot of BS & misinformation floating around. But some info is good. I believe enclosing and venting the battery overboard is the best means for dealing with the catastrophic failure. (Like David has shown you above.)

Materials for your new box/enclosure? Likely some 300 series stainless steel. Powder coated steel may be good too! May be some composite/non metallic that would work. Not sure honestly. Would require a little research and testing.

This isn't brain surgery. But it does require a little "what if" thinking and knowledge of manufacturing & materials. You're trying to brainstorm design of a critical item (to your business and to the users) on a sidewalk in front of a grocery store. Might try to seek out some knowledgeable customers or others friendly to your mission for a little more controlled effort.

2 cents
 
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Sun N Fun is around the corner!

Hi All! Sorry it has been so long since I have been on here but I wanted to put it out there that we will be at Sun N Fun in Florida in April, Hangar A booth 89 and would love for you to stop by and say hi if you are going.

We are also going to The Great Alaskan Aviation show in Anchorage, Alaska May 2-3.

And of course, we are set to be at OSHKOSH in July as well!

Many things have been progressing since our last communications and we are proud to say that we have many OEM manufacturers that we have partnered with and have their stamp of approval. We are working with Glasair Aviation, Fox Aerosport, US Sport Aircraft, Viking Aircraft, Powrachute LLC, Wild West Aircraft and EuroFox Aviation to name a few.

As always, we love to hear from you and based on your input, we do have some new products that builders/pilots like you suggested. Check out our new Quick connect cables at www.earthxmotorsports.com.

Kathy
 
That would be a wonderful idea and the Van's aircraft and the Supercub builders/pilots are the two most common purchasers of our batteries. I will reach out again to them and see what happens. :0) If any one has a direct contact, that would be helpful in getting the information in front of the right people.

Kathy
 
I feel it is worth reiterating that these batteries don't like to be charged like the traditional lead-acid or AGM batteries.

a BMS is critical to keeping any lithium battery happy for a longer time.

I ran through a few of them in my race motorcycle before realizing they weren't worth it. Draining them is extremely damaging to them and it's bound to happen once in a while.

Someday when I get started and get to the firewall forward bits, I plan to use a current day technology lithium battery with a proper BMS to manage how it is charged and to keep an eye on the capacity.
 
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