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EarthX Lithium

EarthX Lithium

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First off, thank you all who have been supporting us over the years and adding your valuable input. We are now officially working with 11 OEM aircraft manufacturers and are endorsed and trusted by their own independent R & D testing departments! Thank you!

As this market is relatively new, there is some gray areas that we want your input with.


We would like to ask all of your for your input about the specs for a lithium iron phosphate battery. It can replace a lead acid battery, but it is not the same. To date, we have tried to write up the spec's in a comparison type language but maybe it's time to revolutionize this area.

A lead acid battery open circuit voltage (OCV) is technically 12.6V. (definition of an OCV is: Open circuit voltage (or potential) is voltage which is not connected to any load in a circuit) but we call it a 12V.

A lithium iron phosphate battery OCV is technically a 13.2V but the industry calls it a 12V so that people know they can use it as a replacement.

We are considering changing how the industry labels the batteries, or at least our batteries, and want to call the voltage 13.2V but we are afraid consumers will think they can not use it as a replacement for a 12v battery. Any thoughts?

Second question, any input on how to label the amp hours? This is an area that is all over the charts from battery manufacturer to battery manufacturer. (and marketing material as well) We want to state exactly how much amperage you have in the event you are using the battery as a deep cycle application such as when your alternator fails. We list both now, what type of equivalent amperage a lead acid battery would have for the amount of cranking power and the usable amp hour. We want to go to listing only the usable amperage but the numbers of what a lead acid might say will look much more in comparison even though it might be less as very few will list the true usable amperage. As an example, if we list the ETX680 as 12.4ah, and the PC680 list theirs as 16, but only have 12.3 usable for an hour) it is confusing. And if you compared another lead acid manufacturer, their listed 18 amp hour might only be 10 usable by design.

Look forward to hearing your input and thank you in advance!

Kathy
www.earthxmotorsports.com

Thanks Vans Forum users
 
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L.A.E or L.A.Q?

How about labeling the batteries and your marketing material with a "Lead Acid Equivalent" marking something like (L.A.E 12v - 18ah) or L.A.Q might be catchier.

earthx_zpsnpwl55p7.jpg
 
Hi Kathy,

First, thank you for your continued efforts to provide 'apples to apples' comparisons; that's what we really need.


But...Statements like the one in your post, that a PC680 is rated at 18AH but only has 12AH usable, makes it look like y'all don't understand battery tech, at least lead-acid battery tech (though most batteries exhibit discharge curves that are similar in nature).

Lead-acid batteries typically have an ampere-hour rating that is based on a "20 hour rate". This means: how many amps the battery can supply, if the discharge is accomplished at a steady rate over a 20 hour window. Any shorter discharge window (higher discharge rate) will *always* result in a lower total AH availability from the battery. In other words, if you can get 20 AH by drawing 1 amp continuously for 20 hours, you will never be able to get 20 AH if you draw at a 20 Amp rate (you'll do good to get 45 minutes at that rate).

Here's a link to the actual specs of a PC680
http://www.odysseybatteries.com/batteries/pc680_series.htm

And here's a link to a pdf of Odessey's performance data sheets (I think I've posted it before).
http://www.odysseybattery.com/documents/US-ODY-TM-002_1214.pdf

Page 6 shows the discharge curve for a PC680. Note from the 1st link that the AH rating of a PC680 is 16AH; not 18AH. Looking at page 6 in the 2nd link, a 0.8 Amp continuous discharge can continue for 20 hours. 20*0.8=16AH. But if you discharge at a continuous 143 Amps, you can only do it for 2 minutes. 2/60*143=4.76AH. Your 12.8 AH usable figure apparently comes (approximately) from the line that shows a 12.3 Amp draw will last for 1 hour.

The chart and the graph give the same info, in different formats

So, if you want to provide comparable data, pick one of your battery models (the 12 AH model?). Determine the discharge rate in amps that will take your battery to the point where it (or its controller) will no longer supply usable power to the load at the end of a 20 hour window. (Odessey specifies 10.02 Volts as fully discharged.) That amp number, times 20, becomes the AH rating of the battery. Then do the same test to determine the current available over a 10 hour window. Etc, etc down (up?) to a 2 minute window. Write up a chart of the numbers, graph it, and publish it. Done.

I see no technical advantage to labeling your battery as 13.x vs 12 volts; but you might sell an extra battery or two to someone who doesn't understand the technical details, if that's a goal you'd want to embrace (I hope it isn't).

Hope that's useful info for you; it's at least what I'm looking for.

Thanks again for your efforts,

Charlie
 
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EarthX Lithium said:
First off, thank you all who have been supporting us over the years and adding your valuable input. We are now officially working with 11 OEM aircraft manufacturers and are endorsed and trusted by their own independent R & D testing departments! Thank you!

As this market is relatively new, there is some gray areas that we want your input with.


We would like to ask all of your for your input about the specs for a lithium iron phosphate battery. It can replace a lead acid battery, but it is not the same. To date, we have tried to write up the spec's in a comparison type language but maybe it's time to revolutionize this area.

A lead acid battery open circuit voltage (OCV) is technically 12.6V. (definition of an OCV is: Open circuit voltage (or potential) is voltage which is not connected to any load in a circuit) but we call it a 12V.

A lithium iron phosphate battery OCV is technically a 13.2V but the industry calls it a 12V so that people know they can use it as a replacement.

We are considering changing how the industry labels the batteries, or at least our batteries, and want to call the voltage 13.2V but we are afraid consuemrs will think they can not use it as a replacement for a 12v battery. Any thoughts?
Click to expand...

Maybe list it as 13.2V and put (12V replacement) somewhere?

Second question, any input on how to label the amp hours? This is an area that is all over the charts from battery manufacturer to battery manufacturer. (and marketing material as well) We want to state exactly how much amperage you have in the event you are using the battery as a deep cycle application such as when your alternator fails. We list both now, what type of equivalent amperage a lead acid battery would have for the amount of cranking power and the usable amp hour. We want to go to listing only the usable amperage but the numbers of what a lead acid might say will look much more in comparison even though it might be less as very few will list the true usable amperage. As an example, if we list the ETX680 as 12.4ah, and the PC680 list theirs as 18, (but only have 12.8 usable) it is confusing. And if you compared another lead acid manufacturer, their listed 18 amp hour might only be 10 usable by design.
Click to expand...

If usable energy changes with the rate at which I'm withdrawing it (which is my understanding of what all batteries do), I don't want just one number. I'd like a graph that showed current draw on one axis and usable lifetime on the other at the specified end-of-life condition for the battery (so if the battery only has, say, 85% of its new capacity after 5 years, give me that graph, not the as-new condition). Otherwise, the number may not be conservative. I know that's not as easy to fit in a spec table, though.

The reason I mention it is that, in a modern electrically-dependent airplane, your current draw may be a lot higher than one or two amps in the event that there is a failure of the alternator(s). I'd rather see a lower figure that I know is realistic for real-world conditions than an arbitrary "standard" figure that might mislead me.
 
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enielsen said:
How about labeling the batteries and your marketing material with a "Lead Acid Equivalent" marking something like (L.A.E 12v - 18ah) or L.A.Q might be catchier.

earthx_zpsnpwl55p7.jpg
Click to expand...

THIS! Anything else is nice for "techno-geeks" but only makes things more confusing for the vast majority of your target market.

My 2 cents.

:cool:
 
Could you make a lithium battery with the equivalent amp-hours rating and external dimensions of a Concorde RG25XC that has a 20lb weight embedded in it so I can keep my CG forward enough?
(now where's that smiley face emoticon with the black eye and missing teeth)
 
Lithium batteries have a negative label because of fires that have occurred with cell phones, lap top computers and even the Boeing Dreamliner.

Successful marketing of the product to GA pilots may depend more on addressing the impression of the fire issue than comparative technical information.

Has the cause of fires been positively identified and fixed?
 
GalinHdz said:
THIS! Anything else is nice for "techno-geeks" but only makes things more confusing for the vast majority of your target market.

My 2 cents.

:cool:
Click to expand...

A lot of lithium battery makers already use that term, and that's what's wrong with their marketing. They use it to describe the battery's ability to crank an engine, which has almost nothing to do with the total *energy* in the battery. Cranking takes 3-5% of a lead acid battery's energy content. With some lithiums, it might consume 20-30%, meaning that the total energy in the lithium is much lower than the lead acid 'equivalent'.

Think Corvette with one gallon of gas vs a Civic with a full tank. The Corvette will be ahead the 1st couple of miles, but the Civic will win the race by several hundred, and move a lot more weight in the process.

Charlie
 
Battery safety

I'm hiding behind the lines of safety! The most powerful battery might be the lightest but if it poisons me with toxic gas or self ignites to barbeque me in flight that is a problem.
I'm sure that there are many that would like to purchase a light weight battery if they knew it was safe including me.
As far as the amp hour rating, I think most aircraft can be run on 10 amps or so in an emergency to the nearest airport. I use about 8 amps running port fuel injection, and 2 fuel pumps. I'm sure most builders look at the amp hour rating before purchasing a battery for their aircraft just for that reason, so it is important to list as much detail as possible so we can get an idea how long it will hold up.
Odyssey battery does a good job listing the details of their batteries on their web site so one can make a well informed decision.
 
RV3bpilot said:
Odyssey battery does a good job listing the details of their batteries on their web site so one can make a well informed decision.
Click to expand...

I agree. Whether you like it or not, the Odyssey was the first sealed small form factor battery to market in RVs. There are probably close to 9,000 Odysseys flying in RVs, with more than 9k planes in the air. The Odyssey battery is (relatively) well understood and has lots of data for us to digest. So naturally, anything you do will, and must, be compared by the end user to the Odyssey.

If you really have a better mouse trap, you have to perform identical tests and publish identical data so that the masses can make a direct comparison and see for themselves that the mouse trap is better. Otherwise folks get skeptical that you're trying to baffle them with bull___.

Read the Odyssey literature (I'm sure you already have), perform the same tests, and publish the results. If some of the data doesn't make sense because the technology is different, that's fine. Publish it anyway, and then explain why it's different. The more clarity you provide, the more likely folks are to embrace your product.

Our lives can depend on our battery. We strive to make well-informed decisions, and we can't be well-informed without directly comparing data.

Unfortunately, even after all that, the entire Lithium chemistry battery industry has a long way to go to convince some of us that the technology won't kill us.
 
Of the 11 OEM Aircraft manufacturers you site, how many of your batteries are in service with them? How many flight hours have they accumulated?
I can sort out the specs later....
 
rv7charlie said:
A lot of lithium battery makers already use that term, and that's what's wrong with their marketing. They use it to describe the battery's ability to crank an engine, which has almost nothing to do with the total *energy* in the battery. Cranking takes 3-5% of a lead acid battery's energy content. With some lithiums, it might consume 20-30%, meaning that the total energy in the lithium is much lower than the lead acid 'equivalent'.

Think Corvette with one gallon of gas vs a Civic with a full tank. The Corvette will be ahead the 1st couple of miles, but the Civic will win the race by several hundred, and move a lot more weight in the process.

Charlie
Click to expand...

Are you talking about Amps/Hour (ah) or Cold Cranking Amps (CCA)? Two different things.

earthx_zpsnpwl55p7.jpg


:cool:
 
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RV3bpilot said:
I'm hiding behind the lines of safety! The most powerful battery might be the lightest but if it poisons me with toxic gas or self ignites to barbeque me in flight that is a problem.
I'm sure that there are many that would like to purchase a light weight battery if they knew it was safe including me.
As far as the amp hour rating, I think most aircraft can be run on 10 amps or so in an emergency to the nearest airport. I use about 8 amps running port fuel injection, and 2 fuel pumps. I'm sure most builders look at the amp hour rating before purchasing a battery for their aircraft just for that reason, so it is important to list as much detail as possible so we can get an idea how long it will hold up.
Odyssey battery does a good job listing the details of their batteries on their web site so one can make a well informed decision.
Click to expand...

I agree with the above... and safety is probably one of the most if not the most critical factor when choosing to switch batteries. I have been using the Odyssey 680 battery in my 7A for 9 years, it has been safe and mostly reliable. Choosing to make the technology switch to a lithium battery (with all of the marketed superior attributes) for me would be considered if:

1. The lithium battery (with better attributes) was PROVEN to be at least as safe as an Odyssey...
2. I was able to due a "plug and play replacement" without any modifications.

One of the things (regarding batteries for EAB aircraft) that has really been very confusing to me is... many of us (in the RV community for example) who have completed aircraft and have been flying with Odyssey 680 batteries for a long time are seeing the newer technology batteries being marketed with some very good attributes that we should (and want) to have in our batteries. Yet, companies like Earth X who want to sell us batteries do not make the battery in a size that will fit in our current installation as a "plug and play" drop-in replacement...? Why is that??? I do not want to modify my battery box to fit the battery... that can be a real PITA. Whenever I see that a new possibly better battery is available, the first thing I look for is the physical size, if the new battery will not fit in my battery box as is without any modification, I generally do not give much consideration to replacing my current battery with the new product...:confused:

In conclusion: Make a better battery (and clearly prove why it's better)... make it safe... make it fit... and make it reasonably priced and I will buy it!!

Thank you for requesting feedback.:)
 
The ideal marketing plan for me would include an honest assessment of the upside AND downside of switching to your product versus an Odyssey 680.

1. Weight savings
2. Charging system modifications
3. Cranking ability--first start and hot/hard start situation
4. Safety considerations re: overheat/runaway
5. Backup ability in the case of charging system failure
6. Trickle charger / battery maintainer requirements
7. Same form factor or hard foam plugs to fit 680 battery box
8. Other than weight savings, why should I switch?
9. Performance in extremes of hot / cold OAT for starting

Don't provide half-truth or incomplete answers or substitute technically accurate, but misleading technical answers when the facts put your product at a disadvantage versus the competition. Whenever I'm shopping for a product and see one of these answers, I immediately discard every other piece of information provided. Not saying you do this because I haven't spent much time looking at your product.

By definition, this group is a technically-oriented lot. We like accurate and truthful information and are generally comfortable deciding for ourselves which trade offs we'll accept. Don't be afraid to admit it if your product isn't better in EVERY aspect. Otherwise, we fall into the "if it sounds too good to be true..." mentality and the focus shifts from making plans to buy your product to "what is it they aren't telling us?"

In my case, the 680 is installed and working on my Midget Mustang. It's easy to stick with the "if it ain't broke" mentality and I don't feel like taking the time to become a battery expert and fact-checking all the claims so I can make a truly informed decision.

IMHO and FWIW and all those other self-effacing disclaimers...:D
 
Completely different

David-aviator said:
Lithium batteries have a negative label because of fires that have occurred with cell phones, lap top computers and even the Boeing Dreamliner.

Successful marketing of the product to GA pilots may depend more on addressing the impression of the fire issue than comparative technical information.

Has the cause of fires been positively identified and fixed?
Click to expand...

Not to get into a long discussion but these are two very different chemistries.

LiFePo batteries are dependable and don't share the bad things of LiPo batteries.
 
Other things to include

Lithem batteries are heat sensitive and this needs to noted. Also please have an indication as to the safety systems included within each battery (each cell) to protect the battery from over charging, direct short to prevent fires etc.. Check out EarthX web site.
 
Thank you all for your input!

First off, thank you all for your input and I hope you continue to write!

Just a couple of things, based on the last comment about liking Odyssey or not.....for the record, we think Odyssey is an excellent lead acid battery and has served the experimental aircraft market well! The lead acid technology has been around for 160+ years and has improved to include AGM batteries and Gel batteries (which contrary to many beliefs, it is a form of a lead acid battery) that has many benefits. They do not come without hazards either, read the warnings on the battery (which is quite extensive), or talk to any one who has had one explode on them or has inhaled the toxic fumes.

Lithium iron phosphate batteries are not new technology, it has been widely used since the 1970's by the military, it is just in the past 5 years that the average consumer can afford this technology. EarthX lithium batteries is an alternative and we are trying our best to educate the consumer and make a product that meets and exceeds your wants and needs. We do not want to create a product in the lab, based solely on engineers perspective, but we want to incorporate the thoughts and opinions of the actual users.

And with all new technology, there will always be people who are resistant and fear the unknown. That is why we are trying so hard to present information to you that is understandable, even though it is different. Without progress of technology, can you imagine where we would be?

I am not an engineer, and I am not even going to try and represent myself as a "teckno geek". But what I do bring to the table is I have talked with hundreds, if not thousands of pilots, mechanics and builders that have used our batteries and many have the same type questions. I have also worked closely with the OEM aircraft manufacturers with their questions and concerns and many have the same type questions.

One question that comes up on every forum (as it has here and even in this thread) and at every trade show is the concern over fire. "Lithium batteries have a negative label because of fires that have occurred with cell phones, lap top computers and even the Boeing Dreamliner." Every one of these lithium batteries are NOT LITHIUM IRON PHOSPHATE cells but instead a Lithium Cobalt cell. The LifePO4 (lithium iron phosphate) chemistry is the safest and most robust of all the chemistries and is the type of cells used in the EarthX brands. But that being said, if a product is abused or misused, there can be consequences. You spill hot coffee on you from McDonalds, even thought it warns you it is hot, you will get burned. If you stick your foot into a running lawnmower blade, even though it warns you not to do it, you will get seriously injured. This is why we have parameters of use and why batteries are not one size fits all.

The second most commonly asked question is on the capacity of the battery. This is one of the most critically important questions. The 20 hr amp rate that have been requested, in useless information. If you are in your plane, and your alternator has failed, are you going to continue to fly for the next 20 hours looking for a place to land? I don't think so. The 1 hour rate, or even 2 hour rate, it what is the most important and critical piece of information you can use. The Odyssey says you have 12.3 amps of power to use in one hour, the EarthX ETX36 says you have 12 amps of power to use in one hour. What does this really mean.....that if you are using 12 amps of power, you better be on the ground in less than an hour. If you are using 6 amps of power, you better be on the ground in less than 2 hours, and if you are using 24 amps of power, you better be on the ground in less than 30 minutes. This seems like important comparison numbers.

Kathy
 
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vasrv7a said:
I agree with the above... and safety is probably one of the most if not the most critical factor when choosing to switch batteries. I have been using the Odyssey 680 battery in my 7A for 9 years, it has been safe and mostly reliable. Choosing to make the technology switch to a lithium battery (with all of the marketed superior attributes) for me would be considered if:

1. The lithium battery (with better attributes) was PROVEN to be at least as safe as an Odyssey...
2. I was able to due a "plug and play replacement" without any modifications.

One of the things (regarding batteries for EAB aircraft) that has really been very confusing to me is... many of us (in the RV community for example) who have completed aircraft and have been flying with Odyssey 680 batteries for a long time are seeing the newer technology batteries being marketed with some very good attributes that we should (and want) to have in our batteries. Yet, companies like Earth X who want to sell us batteries do not make the battery in a size that will fit in our current installation as a "plug and play" drop-in replacement...? Why is that??? I do not want to modify my battery box to fit the battery... that can be a real PITA. Whenever I see that a new possibly better battery is available, the first thing I look for is the physical size, if the new battery will not fit in my battery box as is without any modification, I generally do not give much consideration to replacing my current battery with the new product...:confused:

In conclusion: Make a better battery (and clearly prove why it's better)... make it safe... make it fit... and make it reasonably priced and I will buy it!!

Thank you for requesting feedback.:)
Click to expand...

We do listen and in less than a month, we will be introducing 3 new models that will be a direct replacement for the PC680 physical size. We will offer an equivalent battery, and 2 other batteries with more capacity and cranking amps if you are looking for more! That is why we started this thread, we want to provide you with the information you need to make an informed decision. We are polishing off the details but I can assure you, the Vans Forum here will be the first to hear the official news when we present it.

Kathy
 
EarthX Lithium said:
The Odyssey says you have 12.3 amps of power to use in one hour, the EarthX ETX36 says you have 12 amps of power to use in one hour. What does this really mean.....that if you are using 12 amps of power, you better be on the ground in less than an hour. If you are using 6 amps of power, you better be on the ground in less than 2 hours, and if you are using 24 amps of power, you better be on the ground in less than 30 minutes. This seems like important comparison numbers.
Click to expand...

A previous poster pointed out that, at least for lead-acid technology, this isn't exactly the case. It's overly simplistic to say that drawing 6 amps over 2 hours is the same as drawing 24 amps over 30 minutes. As an example, given the same start and end voltages (discharge to 10.02V under load), Odyssey quotes 21.6A for 30 minutes or 6.9A over two hours. So the 30-minute capacity is 10.8AH (or better yet 118.2WH, as output voltage changes over discharge time) whereas the 2 hour capacity is 13.8AH (157.2WH). In other words, the faster you draw energy out, the less total work the battery can do.

This difference is important, and we'd like to understand what the curve looks like for competitor batteries. Is this data something you already have, or could your company run these tests and publish the results?

(Oh, and to clarify, I didn't intend to imply you didn't like Odyssey. I had simply intended to say that, regardless of whether it is or isn't the best way to characterize a battery, Odyssey's data was published quite some time ago. We're familiar with it. So any newcomers to this market will be compared to the incumbent, and for an easy comparison the data should be presented in a similar format. Sorry for the mis-communication! :eek:)
 
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EarthX Lithium said:
And with all new technology, there will always be people who are resistant and fear the unknown.
Click to expand...
And in addition to these poor, ill-informed Luddites there will be some educated and thoughtful potential customers who are skeptical of marketing claims (especially from those who profess not to be "techno-geeks"). These people will want to make an informed decision before abandoning a proven, time tested and very well understood technology.

The Boeing fires (and all the others) don't help matters either. I didn't know until I did some research that those batteries were a different chemistry, and apparently much more prone to such events. Yes, you can get a lead acid battery to catch fire or explode, but avoiding that is pretty well understood. People are understandably a little reluctant to tread where the likes of Sony, Dell, Toyota, Tesla, Boeing and others have failed.
EarthX Lithium said:
That is why we are trying so hard to present information to you that is understandable, even though it is different. Without progress of technology, can you imagine where we would be?
Click to expand...
I would point out that we're a bunch of experimental aircraft builders and are often on the bleeding edge of technology. You're kind of barking up the wrong tree with that statement. We're all looking for something better, but "better" has to be proven.
EarthX Lithium said:
The second most commonly asked question is on the capacity of the battery. This is one of the most critically important questions. The 20 hr amp rate that have been requested, in useless information. If you are in your plane, and your alternator has failed, are you going to continue to fly for the next 20 hours looking for a place to land? I don't think so. The 1 hour rate, or even 2 hour rate, it what is the most important and critical piece of information you can use. The Odyssey says you have 12.3 amps of power to use in one hour, the EarthX ETX36 says you have 12 amps of power to use in one hour. What does this really mean.....that if you are using 12 amps of power, you better be on the ground in less than an hour. If you are using 6 amps of power, you better be on the ground in less than 2 hours, and if you are using 24 amps of power, you better be on the ground in less than 30 minutes. This seems like important comparison numbers.
Click to expand...
Spot on! That kind of numbers along with cranking amps are exactly what I would be looking for when selecting a battery.

One other question I have... while I love the Li chemistry batteries in a lot of devices, I have noted that the larger packs have a tendency to operate at close to 100% right up until the end... then shut off completely with no advance warning signs. A stone age AGM or wet cell will give me a clear indication when it's near the end of its rope, and will continue to produce power (albeit at a reduced and declining voltage) until it gives its last gasp. Do your batteries exhibit this sudden stoppage when they feel they're depleted, or not? That would be a factor for me.

I'm also a little concerned about the performance in a consistently hot environment like under the cowling of an RV, tucked in behind a grunting, straining hunk of Lycoming's best.
 
krw5927 said:
A previous poster pointed out that, at least for lead-acid technology, this isn't exactly the case. It's overly simplistic to say that drawing 6 amps over 2 hours is the same as drawing 24 amps over 30 minutes. As an example, given the same start and end voltages (discharge to 10.02V under load), Odyssey quotes 21.6A for 30 minutes or 6.9A over two hours. So the 30-minute capacity is 10.8AH (or better yet 118.2WH, as output voltage changes over discharge time) whereas the 2 hour capacity is 13.8AH (157.2WH). In other words, the faster you draw energy out, the less total work the battery can do.

This difference is important, and we'd like to understand what the curve looks like for competitor batteries. Is this data something you already have, or could your company run these tests and publish the results?

(Oh, and to clarify, I didn't intend to imply you didn't like Odyssey. I had simply intended to say that, regardless of whether it is or isn't the best way to characterize a battery, Odyssey's data was published quite some time ago. We're familiar with it. So any newcomers to this market will be compared to the incumbent, and for an easy comparison the data should be presented in a similar format. Sorry for the mis-communication! :eek:)
Click to expand...

We do have this data, it is in our manual on the website and for a lithium battery, it is that simplistic. Just at the Odyssey has discharge curves, so do we. As you will note, the discharge curve is very different. Also, many of the questions that are being asked in this thread have been addressed in our manual as well.

And I would like to send out a thank you to all of you that have called me today to express your "concerns" about how some of the responders seem a bit too harsh. Many of you I have had the pleasure of meeting in person and over the years of you using the batteries, we have built up a relationship which is one of the great joys of my job. I am but one person at EarthX and I am not the engineering department. And quite frankly, this is why manufacturers do not attempt to participate in a public forum such as this as there will always be negative people that believe companies are only out to "get" the consumer. We do understand. We look forward to over the years winning your respect and trust and for some it will take time, and that is OK!

Kathy
 
EarthX Lithium said:
And I would like to send out a thank you to all of you that have called me today to express your "concerns" about how some of the responders seem a bit too harsh. Many of you I have had the pleasure of meeting in person and over the years of you using the batteries, we have built up a relationship which is one of the great joys of my job. I am but one person at EarthX and I am not the engineering department. And quite frankly, this is why manufacturers do not attempt to participate in a public forum such as this as there will always be negative people that believe companies are only out to "get" the consumer. We do understand. We look forward to over the years winning your respect and trust and for some it will take time, and that is OK!

Kathy
Click to expand...

He he... I won't call but will post right here. This is one of the most civilized forums on the web today. I could name at least 10 in the car, boat, ROTARY subjects that are like running a gauntlet of egos and misinformation.

Thanks to the host Doug Reeves and the admins for keeping us in line.

[Oh yea... you might want to consider advertising on this site. That way, I'll remember you when it's time to buy my battery. ;)] edit*** I see you in the side bar already... looking forward to your advancements!

Cheers.
 
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2 angles of marketing

Lets say we are all on board with the LiFePo technology. There are two areas for marketing as I see it.

1) Those that are flying and are using the PC680.

2) Those who are building and desire to take advantage of the smaller sized battery 36C and 36D.

So, if I were the marketing arm of EarthX, here would be my methodology.

Obviously, you are well along in the development of a drop in replacement for the 680. This is very important and covers those already flying.

Now, I would design a battery box that fits the 36C and the 36D. Get a battery box kit from Van's. Use it to design a battery box for the 36C and 36D. Done.

Now you've got those flying and using a 680 and those building who want to save firewall space with the smaller batteries.
 
Another suggestion I have that would work well wining over customers here is to select 10 frequent posters on this form with different type RVs who fly lots and give them one of your batteries for field trials. As well as advertise on this web site, when selecting RVers think different type missions. For example training;), aerobatics, racing, lots of daily x-countries,(think Vlad:D) etc. Another factor to consider is climate they operate in. In Texas we operate in 100F plus during the summer! Then ask them to post their findings on the form. Consider giving some batteries to Vans Aircraft, their demonstrators fly continuously. Good luck and keep us up to date on how testing goes.:)
 
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That's not a bad idea, offering a battery box kit. Since the perceived hazard is fire, I'd prefer that the battery box be sealed and vented and fabricated of stainless steel.

Dave
 
Dear Vans Forum users,

Besides this dialog, many of you also send direct emails with questions as well and I would like to try and address some common questions. Many of you want to know if the replacement will be an EXACT plug and play replacement for the PC680. The answer is no.

Here are some ?issues? with an EXACT replacement. The PC680 is actually tapered in its width, the widest at the top (80mm) and then it gets skinnier at the bottom (76.3mm) and they have a completely different profile of the top of their battery as well. Actually, all lead acid batteries are designed with the ?cup? type tapering whereas a lithium is not. We are the same width from top to bottom.

Our new case dimension will be 166mm (L) x 80mm (W) x 170mm (H) .
The PC680 dimensions are 181.5mm (L) x 76.3mm (W) x 167.8mm (H).

The new EarthX case size fits in all the existing battery box type holders with a minimum of adjustments. As you know, there are many different aftermarket manufacturers and options out there.

Then questions about vibration issues,-- it is a powder type substance inside the case with no vibration issues, unlike any lead acid battery, you will have lead plates that can and do vibrate. This is not an issue for a lithium.

Temperature: the PC680 is rated at -40C to 45C and our battery is rated at -30C to 60C. We are not quite as good in cold but higher ratings for hot.

It is becoming very clear to us that consumers want a turnkey solution and offering battery boxes is a necessity. We have been working towards this and have aluminum and titanium prototypes now but have not made any final decisions on a manufacturer of these boxes as of yet.


Not sure about a steel box as it is heavy and not structurally needed to hold in place a 3.9 pound battery. (The melting point of titanium is 1,668 deg C, aluminum is 660.3 deg C, and steel is 1,510 deg C. )

Thanks again all of you!

Kathy ([email protected])
 
I've hesitated in switching due to couple of factors, with the main one being that I didn't want to build a custom box to replace the PC680. I want the ability to quickly drop in a PC680 in the field should I be forced to replace the battery if traveling or away from my home field.

My other concern(s) deal with the operating state of the battery. The PC680 is simple, proven and a durable battery that requires little monitoring other than voltage. For me to feel more comfortable with these newer technology batteries, I would like to monitoring the battery in more detail.

So, here are a couple of suggestions that may help relieve some of my concerns on the operating status of the battery:

1) Add a built-in temp sensor to the battery pack. Most EFIS vendors have one or more spare temp sensor inputs that are configurable that could be used to display this data. I would like to monitor the internal core temp of the battery and let my EFIS alert me if the temps are either too high or too low based upon EarthX suggested operating range. Yes, I know I could add a external surface mounted temp sensor, but that would not be as accurate as an internal core temp.

2) Add a annunciator signal line. This could be used with/with out a EFIS. It would be a simple signal wire that your circuitry would ground when a "caution" condition is detected within your circuit logic. This could drive a annunciator light or as a input to a EFIS to raise an alarm on the screen.

Maybe in the more distant future, partnering with the EFIS vendors to develop a protocol for communicating the state of the battery, possibly at each cell level would help visually monitoring the usage and health of the battery and possibly help spot gradual degradation of the battery or unusual operating characteristics.
 
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kbehrent said:
"1) Add a built-in temp sensor to the battery pack."
"2) Add a annunciator signal line."

Thank you for this and both of these items are being designed, engineered and tested for future models. We have been working on a certified battery but this process is very lengthy, time consuming, and EXPENSIVE. There is only one company out there right now that does have a certified lithium iron phosphate battery and the starting price is $4,000.


Kathy
Click to expand...
 
EarthX Lithium said:
It is becoming very clear to us that consumers want a turnkey solution and offering battery boxes is a necessity. We have been working towards this and have aluminum and titanium prototypes now but have not made any final decisions on a manufacturer of these boxes as of yet.

Not sure about a steel box as it is heavy and not structurally needed to hold in place a 3.9 pound battery. (The melting point of titanium is 1,668 deg C, aluminum is 660.3 deg C, and steel is 1,510 deg C. )

Kathy ([email protected])
Click to expand...

An aluminum box could be a really good choice for those folks putting the battery box inside their fuselage. Glad to see this option.

A titanium box, while lightweight and strong, will be susceptible to embrittlement and stress corrosion cracking where in contact with cadmium-plated bolts used to mount the battery box. Not difficult to mitigate, but worthwhile. Stainless steel hardware and explicit mounting instructions might be one option.

A lightweight steel box is friendly with cadmium-plated fasteners and the firewall material, and can survive a fire on the hot side of the firewall.
 
New Battery....

Kathy,
It is great to hear of the redesigns for a drop in replacement battery (PC680) and considerations in design incorporation of sensors plus battery mount/cases.

I guess you might call me a future repeat customer, sort of since, I did own two of your battery's about one year ago but then sent them back because I did not have the time to redesign the battery box to accommodate the batteries I purchased for the RV10. The repeat customer portion will soon occur... your phone will ring again with the release of the 3 new batteries I am very sure.:)

When might the sensor technology be released? You mentioned it in a prior thread but I wast sure if this meant the latest battery release coming in a month or future time frame.
 
I'm late to the party, but I've been tangled in wires getting my panel installed all week!

First off, I have an EarthX ETX36C in my RV10. No modification required to the battery tray, other than a plastic spacer I made up to keep everything in place. This battery is TINY and LIGHT!

I did quite a bit of research on the different battery chemistry options before I ordered, and I'm comfortable with the minimal risks that these batteries have.

That said, I think the best thing you could do is post a few videos of you guys destroying a few of your batteries!

Some people are under the impression that a LiFePo4 battery will explode, leak toxic gas, kick their dog, and insult their mothers as they kill you. I think people would be much more receptive to the new technologies if you SHOWED them the possible failure modes. Take a video of you overcharging it, or applying 30 volts (should be a nothing burger with the BMS). Discharge it until it's DEAD (again, BMS should make this pretty boring)... but boring is good!

Then, make it interesting. Hook a battery up to some lights, and hit it with a weed burner torch:
BP223_1.jpg


Show what happens when it catches on fire while current is being drawn.

Then for the final test, again hook it up to some lights, then run a drill right thru the middle of the battery!

Total cost: 4 batteries and a weed burner torch. I bet it sells more than 4 batteries for you guys!
 
EarthX Lithium said:
We do listen and in less than a month, we will be introducing 3 new models that will be a direct replacement for the PC680 physical size. We will offer an equivalent battery, and 2 other batteries with more capacity and cranking amps if you are looking for more! That is why we started this thread, we want to provide you with the information you need to make an informed decision. We are polishing off the details but I can assure you, the Vans Forum here will be the first to hear the official news when we present it.

Kathy
Click to expand...

Sweet! This is the best news I've heard about LiFePo since I first heard about them. The ship has sailed for me (I fabricated a custom battery box), but great news for others wanting to switch.

I also like the option to bump up in size. More power and still less than 1/3 the weight of a PC680. :)
 
EarthX Lithium said:
Dear Vans Forum users,

Besides this dialog, many of you also send direct emails with questions as well and I would like to try and address some common questions. Many of you want to know if the replacement will be an EXACT plug and play replacement for the PC680. The answer is no.

Here are some ?issues? with an EXACT replacement. The PC680 is actually tapered in its width, the widest at the top (80mm) and then it gets skinnier at the bottom (76.3mm) and they have a completely different profile of the top of their battery as well. Actually, all lead acid batteries are designed with the ?cup? type tapering whereas a lithium is not. We are the same width from top to bottom.

Our new case dimension will be 166mm (L) x 80mm (W) x 170mm (H) .
The PC680 dimensions are 181.5mm (L) x 76.3mm (W) x 167.8mm (H).

The new EarthX case size fits in all the existing battery box type holders with a minimum of adjustments. As you know, there are many different aftermarket manufacturers and options out there.

Then questions about vibration issues,-- it is a powder type substance inside the case with no vibration issues, unlike any lead acid battery, you will have lead plates that can and do vibrate. This is not an issue for a lithium.

Temperature: the PC680 is rated at -40C to 45C and our battery is rated at -30C to 60C. We are not quite as good in cold but higher ratings for hot.

It is becoming very clear to us that consumers want a turnkey solution and offering battery boxes is a necessity. We have been working towards this and have aluminum and titanium prototypes now but have not made any final decisions on a manufacturer of these boxes as of yet.


Not sure about a steel box as it is heavy and not structurally needed to hold in place a 3.9 pound battery. (The melting point of titanium is 1,668 deg C, aluminum is 660.3 deg C, and steel is 1,510 deg C. )

Thanks again all of you!

Kathy ([email protected])
Click to expand...

Kathy, what are these 'mm' and 'C' units you're speaking of for units of length and temperature?

But seriously, it's refreshing to see the metric system used here in the US. :)
 
Rotax 912iS Mandatory Alert

One of our aircraft manufacturers sent this alert to us today and thought it was important information to pass on. It was a mandatory alert sent out on May 29, 2015 by Rotax concerning the use of lithium batteries in aircraft.

What I found exciting and interesting is they actually copied verbatim from our spec's and website the features the BMS must have to be approved.

Here is a copy of the alert:
NEW RELEASE
MANDATORY
ROTAX 912i (series)
ALERT SERVICE BULLETIN:

"The use of lithium-ion batteries in combination with the ROTAX Engine Type 912 i Series"
ASB-912 i-005iS
ROTAX 912iS & 912iS Sport aircraft engines are approved for operation with lithium-ion batteries if the aircraft has been equipped with a suitable battery management system (qualified by the aircraft manufacturer).

This requirement has been specified in the 912 i (series) installation manuals since Edition 1 Revision 2. The purpose of this bulletin is to bring this to the attention of users of engines delivered with earlier (Rev.0 or Rev.1) versions of the installation manual.

This is a MANDATORY alert service bulletin, and users of lithium-ion batteries should verify that their battery includes a suitable battery management system BEFORE THE NEXT FLIGHT.


WHY USE A BATTERY MANAGEMENT SYSTEM?
Lithium batteries are fundamentally different than lead-acid batteries. If overheated or overcharged, Li-Ion cells are prone to accelerated cell degradation and can catch fire or even explode. The lithium cells inside the battery need electronics to monitor and balance the voltage & charge level of the individual cells.

Some older types of lithium batteries require an external balancing charger, which you have to plug in periodically to ?top off? and balance the cells. These kinds of batteries are NOT approved.
The more modern lithium batteries have a built-in microprocessor Battery Management System (BMS) that continuously monitors the charge level of each cell and balances the charge when needed, protecting the cells from overcharge or over-discharge. Some can also provide short circuit protection, and excessive cranking protection.

Typically, the individual cells in a battery have somewhat different capacities and may be at different levels of state of charge (SOC). Without balancing, the cell of smallest capacity is a "weak point", it can be easily overcharged or over-discharged while cells with higher capacity undergo only partial cycle. For the higher capacity cells to undergo full charge/discharge cycle of the largest amplitude, balancer should ?protect? the weaker cells; so that in a balanced battery, the cell with the largest capacity can be filled without overcharging any other (i. e. weaker, smaller) cell, and it can be emptied without over-discharging any other cell. Battery balancing is done by transferring energy from or to individual cells, until the SOC of the cell with the lowest capacity is equal to the battery's SOC.

A full battery management system (BMS) might include active balancing as well as temperature monitoring, charging, and other features to maximize the life of the battery pack.

Bottom line: if you use a lithium battery in your aircraft, make sure it includes a built-in Battery Management System.

Here is the link to the actual alert: http://legacy.rotaxowner.com/si_tb_info/alertbulletins/asb-912i-005is.pdf

Kathy
 
NEW AIRCRAFT BATTERY MODELS ARE HERE!

As promised to the Van's forum readers, you are the first to know that the new aircraft lithium batteries are now available for pre-order on the website and they are scheduled to ship at the end of July 17th week.

All of our batteries meet the criteria set forth by Rotax to be an approved lithium battery, (and we are the only lithium battery on the market to have this approval), but what these 3 new models bring (ETX680, ETX900, ETX1200) in addition to what the other models have is:
1. Redundant electronics for the BMS board
2. LED battery fault light indicator that can also be plugged into your control panel.
3. A higher cranking, more capacity models (ETX900, ETX1200) if you need or want more.

These new models will fit into any preexisting PC680 battery box hardware and we are also going to have an aluminum battery box for sale as well on the site that is rated for 30 G Force, and 7 ounces of weight. That isn't on the site yet, but by end of tomorrow it should be there. Check it out at www.earthxmotorsports.com

Thanks Van's for all your support!

Kathy
 
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EarthX Press Release January 18, 2016

Dear Vans readers, as promised, we at EarthX said we would make new announcements here and we know many of you not only fly an RV but have other aircrafts as well, including a Sonex aircraft so here is our exciting press release news today:

EarthX now approved by Sonex Aircraft, LLC!​
January 18, 2016, Windsor, CO
EarthX Motorsports is proud to announce that a Sonex Aircraft has become a dealer for the complete line of EarthX products. Sonex has tested the EarthX aircraft battery line and approves their use in Sonex Aircraft designs.
EarthX currently has 3 battery models designed specifically for the aircraft market; the ETX680, ETX900 and the ETX1200. EarthX lithium batteries can significantly decrease the weight of your aircraft (11+ pounds instantly) and increase your cranking amps all with one product! All of these aircraft models have a fully integrated battery management system (BMS) that is also redundant and have an LED battery fault light indicator that can be used in your EFIS system or a simple LED light on your panel. EarthX aircraft batteries meet the requirements set forth by Sonex Aircraft, for all Sonex engine installations, and for the AeroConversions AeroVee line of engines for use on any airframe. The BMS provides over discharge protection, over charge protection, short circuit protection, and excessive cranking protection (temperature sensing) in addition to integrated cell balancing technology. Check it out at www.earthxmotorsports.com

Sonex Aircraft, LLC is a leader in the experimental kit aircraft industry, providing a series of sport aircraft along with the AeroConversions line of products, which include the AeroVee engine, AeroVee Turbo, AeroInjector and ancillary aviation products. Sonex Aircraft?s Sonex, Waiex, and Onex sport planes, the Xenos sport motorglider, and the SubSonex Personal Jet, offer outstanding performance in an easy to build, easy to fly kit package that can be purchased and completed with full technical support at an unrivaled price. Highly regarded as an engineering company, Sonex has diversified its offerings to include the Teros line of UAV aircraft for civil and defense missions in conjunction with Navmar Applied Sciences Corporation. Sonex and AeroConversions continue to invest heavily in developing new products. Our team is committed to providing simple, elegant and low-cost solutions for sport flying. Simply put, Sonex Aircraft and AeroConversions products provide the Best Performance Per Dollar. Check us out at www.SonexAircraft.com and www.AeroConversions.com
 
NovaBandit said:
I did quite a bit of research on the different battery chemistry options before I ordered, and I'm comfortable with the minimal risks that these batteries have.

That said, I think the best thing you could do is post a few videos of you guys destroying a few of your batteries!

Some people are under the impression that a LiFePo4 battery will explode, leak toxic gas, kick their dog, and insult their mothers as they kill you. I think people would be much more receptive to the new technologies if you SHOWED them the possible failure modes. Take a video of you overcharging it, or applying 30 volts (should be a nothing burger with the BMS). Discharge it until it's DEAD (again, BMS should make this pretty boring)... but boring is good!
Click to expand...

As mentioned in the Rotax bulletin and a few other places, the battery management system is KEY.

One of my work colleagues is the guy that successfully certified the LiFePo4 battery for aircraft for another company as mentioned above. Yes the process was grueling. And in discussions with him, it turned out that it was not practical to try to certify a battery for our price point and market size.
From him:
"While it is true that LiFePo4 batteries won't explode like a LiCoO2 battery, they will, if mistreated, overheat to the point where the battery case and internals will melt and burn, and give off some pretty nasty organic compounds as exhaust. The only sure-fire way to make these batteries safe enough to be in the interior of an aircraft is to be in a fire-proof enclosure with a vent tube to the exterior of the aircraft."

A different manufacturer of LiFePo4 batteries that suits our mission (NOT EarthX) claims to have a built-in BMS, yet when their 12V equiv. battery was connected to a 24V charger, the case swelled badly and it got very hot before the charger was disconnected. So, as consumers, we need to be pretty skeptical.

It would go a long way to consumer acceptance to show some of the tests as described by NovaBandit. Given that I already know of one supplier whose BMS doesn't do what it should, show us that yours does.
It counts for a lot that you describe the BMS is some detail, but even better to see it in action.
With a high-confidence BMS, the risk trade-off of using these batteries without a vented enclosure gets more reasonable, probably approaching the safety level of a lot of other systems we rely on.

Just as an example of why caution is needed: I would also be interested in an 8 Ah equiv battery to use in my sailplane. That battery gets recharged with a battery charger. On your website you have a list of compatible chargers, and note several that are not, because they have a de-sulfating mode that will over-voltage the battery, and you use the caution "Do not use, as full time de-sulfating mode will damage a lithium battery". BUT...wouldn't the BMS protect the battery from the excessive voltage of the de-sulfating mode? If not, then how do I trust your BMS?

If the BMS does not protect against over-voltage, then we are relying on the over-voltage protection built into the alternator. I wonder what the failure statistics are on those?
 
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thread bump

I was really hoping that the folks at EarthX would respond to my questions here. They appeared to be very timely in their replies to earlier questions, but perhaps have stopped monitoring the thread? I would like very much to upgrade to LiFePo4, especially in my sailplane. But I would like to hear their reply to this first.

Please?


scsmith said:
As mentioned in the Rotax bulletin and a few other places, the battery management system is KEY.

One of my work colleagues is the guy that successfully certified the LiFePo4 battery for aircraft for another company as mentioned above. Yes the process was grueling. And in discussions with him, it turned out that it was not practical to try to certify a battery for our price point and market size.
From him:
"While it is true that LiFePo4 batteries won't explode like a LiCoO2 battery, they will, if mistreated, overheat to the point where the battery case and internals will melt and burn, and give off some pretty nasty organic compounds as exhaust. The only sure-fire way to make these batteries safe enough to be in the interior of an aircraft is to be in a fire-proof enclosure with a vent tube to the exterior of the aircraft."

A different manufacturer of LiFePo4 batteries that suits our mission (NOT EarthX) claims to have a built-in BMS, yet when their 12V equiv. battery was connected to a 24V charger, the case swelled badly and it got very hot before the charger was disconnected. So, as consumers, we need to be pretty skeptical.

It would go a long way to consumer acceptance to show some of the tests as described by NovaBandit. Given that I already know of one supplier whose BMS doesn't do what it should, show us that yours does.
It counts for a lot that you describe the BMS is some detail, but even better to see it in action.
With a high-confidence BMS, the risk trade-off of using these batteries without a vented enclosure gets more reasonable, probably approaching the safety level of a lot of other systems we rely on.

Just as an example of why caution is needed: I would also be interested in an 8 Ah equiv battery to use in my sailplane. That battery gets recharged with a battery charger. On your website you have a list of compatible chargers, and note several that are not, because they have a de-sulfating mode that will over-voltage the battery, and you use the caution "Do not use, as full time de-sulfating mode will damage a lithium battery". BUT...wouldn't the BMS protect the battery from the excessive voltage of the de-sulfating mode? If not, then how do I trust your BMS?

If the BMS does not protect against over-voltage, then we are relying on the over-voltage protection built into the alternator. I wonder what the failure statistics are on those?
Click to expand...
 
scsmith said:
I was really hoping that the folks at EarthX would respond to my questions here. They appeared to be very timely in their replies to earlier questions, but perhaps have stopped monitoring the thread? I would like very much to upgrade to LiFePo4, especially in my sailplane. But I would like to hear their reply to this first.

Please?
Click to expand...

Dear scssmith,

I do apologize for not responding to your posting in a timely manner. Please know you can always contact us directly as [email protected] or call (970) 674-8884 or send us a message via the forum if you have a question that needs a more immediate response as we may not see a posting.

You mention ?consumer acceptance? which is very important to us as well and we have made a lot of gains in not only the consumer arena but also in the industry itself. We do currently have the endorsement for approval from Rotax Engines, Continental Motor Engines, UL Power Engines, Viking Engines and Aerovee Engines used in Sonex aircrafts. We also have 20+ aircraft manufacturers such as Sonex, Kitfox, Bristell, Glasair, Revo, Powrachute, Eurofox, STOLquest, Evolution Aircraft, Scion Helicopters, Mosquito Helicopters, Backcountry Supercubs etc. to name a few that have tested the EarthX batteries by their own independent engineers and tests and have approved, endorsed and are using the EarthX brand. If you are interested in the tests performed, we are designing, testing and building the batteries to the requirements set forth in the FAA Certified lithium battery requirements. (Note, they are not certified batteries at this time)!

As far as a battery for your sailplane, I do understand you only need 8 Ah but I would recommend the ETX680C which has 12.4 but it is the aircraft specifically designed battery with a redundant BMS and LED fault light indication that would alert you to many different things such as state of charge, faulty BMS component or if you have a weak cell.
To address the question about not using a desulfination type charger: these chargers send pulses of very high voltage (can be over 30V) extremely fast designed to knock the sulfation off of lead acid plates. The over voltage protection in the BMS designed to protect from a faulty charger or faulty alternator with a voltage that is constant or rising above the normal acceptable range which can be detected and protected against. This is why all lithium batteries caution not to use a desulfination type charger.

Hope that addresses your questions and as always,

Fly Lightly,
Kathy
 
hendrik said:
Are these desulfination pulses something you can catch with a TVS diode?
Click to expand...

The simple answer is "no" as the TVS diode works within a range of voltage. This is why all lithium batteries (all chemistries even) say to not use a desulfination type charger.

Thanks for the question.

Fly Lightly,
Kathy
 
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