EarthX does monitor this site. I know they have lots of batteries out there now, and I trust that Kathy would speak up if they were having problems and/or believed the risk was too high for us.
Vic
Vic
Van's Air Force
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A very lucky pilot! (LI Iron Battery)
- Thread starter sailvi767
- Start date
PilotjohnS
Well Known Member
Changes
The li ion chemistry is changing all the time and I am no longer keeping up with it for my day job; i will not render an opinion on any specific battery because i dont have enough experience with the aircraft types. The quote above is my opinion and we all can make are own decisions, suffice it to say please heed the advice of others and become educated and evaluate the risks of any new technologies for yourself. In this hobby ignorance is not an option. If you want more info on the why i feel the way i do, you may PM me.JMHO
The li ion chemistry is changing all the time and I am no longer keeping up with it for my day job; i will not render an opinion on any specific battery because i dont have enough experience with the aircraft types. The quote above is my opinion and we all can make are own decisions, suffice it to say please heed the advice of others and become educated and evaluate the risks of any new technologies for yourself. In this hobby ignorance is not an option. If you want more info on the why i feel the way i do, you may PM me.JMHO
Vic, the "I trust" statement sounds like "I hope". my neighbor has an EarthX that had a warning light that illuminated but it was difficult to see on the battery. he has now wired the new EarthX battery warning light inside the cockpit. he made it for Florida and back but carried a spare Odessey just in case.
Sorry if trust sounded like hope. I certainly don't believe in hope when it comes to airplanes.
I will follow up with them. I know we have a good many of us running the Earthx batteries, and I know of one fault light that came on so far and they imediately replaced the battery.
Vic
Sorry if trust sounded like hope. I certainly don't believe in hope when it comes to airplanes.
I will follow up with them. I know we have a good many of us running the Earthx batteries, and I know of one fault light that came on so far and they imediately replaced the battery.
Vic
I'm probably #2, but it was a great experience with EarthX. Last summer I got the slow flashing light from my ETX-900 (battery fault). I immediately contacted EarthX, who asked me to send the battery to them immediately. Meanwhile, they immediately sent me a new battery (warranty and all). My takeaways:
- Unlike the battery in the OP's post, the EarthX battery has dual redundant battery management computer systems. Like Paul Dye said, they WORK.
- As soon as the battery management system sensed a fault, no matter how slight, it warned me, and let me take action.
- Derivatives of the root word IMMEDIATE showed up several times in Vic's and my narrative above. I like GA-supporting businesses that work that way, especially regarding my aircraft.
My 2 cents...
grubbat
Well Known Member
Earthx
I had a light come on my fairly new Earthx. They "immediately" replaced it, at no cost to me or any questions asked other than me describing the fault. Excellent customer service.
I had a light come on my fairly new Earthx. They "immediately" replaced it, at no cost to me or any questions asked other than me describing the fault. Excellent customer service.
I'm probably #2, but it was a great experience with EarthX. Last summer I got the slow flashing light from my ETX-900 (battery fault). I immediately contacted EarthX, who asked me to send the battery to them immediately. Meanwhile, they immediately sent me a new battery (warranty and all). My takeaways:
- Unlike the battery in the OP's post, the EarthX battery has dual redundant battery management computer systems. Like Paul Dye said, they WORK.
- As soon as the battery management system sensed a fault, no matter how slight, it warned me, and let me take action.
- Derivatives of the root word IMMEDIATE showed up several times in Vic's and my narrative above. I like GA-supporting businesses that work that way, especially regarding my aircraft.
My 2 cents...
If the impetus for going to the EarthX is weight savings, I fail to see how carrying a "spare" Odyssey makes any sense.
Is there any reason for using the light-weight lithium-based batteries other than weight savings?
[Not yet convinced] ..............
curious as to the shipping method for returned EarthX batteries with a blinking light. any extra precautions needed?
bret
Well Known Member
That's a good question on the shipping, and I would bet that it depends upon the fault. The one fault that I am aware of seemed to be a blance issue and is not considered a safety of flight issue. Nonetheless, they immediately replaced it.
Keep in mind that EarthX batteries have been used in many production Sport aircraft for a long time now. So the field of installed batteries is getting pretty large and we should see if there are any problems.
Vic
Keep in mind that EarthX batteries have been used in many production Sport aircraft for a long time now. So the field of installed batteries is getting pretty large and we should see if there are any problems.
Vic
grubbat
Well Known Member
EarthX
For me, the weight saving was needed to help offset the heavy constant speed prop. Also, the EarthX cranks the engine like a scalded dog, even when it's cold out. I like the EarthX approach and with the excellent customer service, I am satisfied with their products.
For me, the weight saving was needed to help offset the heavy constant speed prop. Also, the EarthX cranks the engine like a scalded dog, even when it's cold out. I like the EarthX approach and with the excellent customer service, I am satisfied with their products.
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Fear
Good Morning Van's forum,
Thank you for those who contacted me to let me know about this thread. I will admit, I do not monitor it enough so please know you can ALWAYS contact us for questions or concerns, we are here to assist you.
Couple of quick answers to questions:
1- How do you ship the battery back? In the event you have a possible problem and have an illuminated light, we send you a replacement battery in a ground shipment box that is labeled correctly for shipping a lithium battery and inside is the prepaid return label. All you do is remove new, put in "old" and it comes back to us. A blinking light or a solid light does not mean it is a shipping hazard.
2- What does the blinking or solid light alert you to? I am going to copy and paste from the manual on the aircraft batteries and there is also a checklist chart that will come with your battery but can also be found in the manual a well:
ETX Hundred Series - BMS
The ETX ?Hundred Series? was specifically designed for the experimental aircraft market (models include the ETX680C, ETX680, ETX900, ETX1200). Only the ETX ?Hundred Series? battery models are recommended for use as the primary aircraft battery (starter battery). In addition to the features found in the ETZ and ETX series motorsports batteries, critical electronic circuits are redundant, the over-charge protection is enhanced and fault indication is included.
All components associated with main electronic battery disconnect are redundant. The built-in redundancy ensures that no single point failure results in the battery unintentionally disconnecting. The design aligns with the requirements for a FAA approved lithium battery as per RTCA performance specification DO-311.
In the event of a charging system failure where the voltage increases to above 15.2V, the resistance to charging current increases, and above 16V the charging current is completely blocked. This design offers charge voltage protection greater than 40V. The discharge current (current out of battery) is unaffected in this situation.
The battery?s micro-controller monitors all failure modes, and reports failures with a built-in LED indicator and discrete output. The discrete output for external fault monitoring is a single wire connection with ?? quick connect terminal. The output is a ?current sinking? type circuit (see diagram below) that can handle 100mA (connects the discrete output to battery ground if a fault is present). This output can be connected to an external 12V LED or general purpose discrete input of an EFIS. The fault output has two states; slow flashing (5 second cycle time) or solid.
The slow flashing fault can indicate an improper state of charge or a problem with the cells internal to the battery. If the battery voltage is outside the normal range of operation, 12.8V to 14.6V, the battery is over-discharged or over-charged, most likely the result of an issue with the electrical/charging system. If the battery voltage is within the normal operating range, with a slow flashing fault, it is indicating an abnormal condition with a cell, such as one cell?s state of charge is very different as compared to the other cells (high cell charge level imbalance). The slow flashing fault may come on briefly during or following periods of high current charging, and is not a concern. But if the fault persist, comes on consistently during changing, or remains (charging or not), the battery will need to be replaced.
The solid fault indicates a BMS hardware failure. For example, if the micro-controller fails the fault indication output is activated (on solid). If the fault persist, comes on and stays on, the battery will need to be replaced.
3- Fear. We at EarthX have dedicated ourselves to the experimental aircraft market to provide a safe product and continuously research and implement features to reflect this. We attend many aircraft tradeshows and present in their forums to educate and provide an opportunity to ask questions too. We have had the opportunity to work with many aircraft manufacturers and engine manufacturers to integrate the most robust, safe, lithium battery option for our users on the market today. We have added the remote LED fault light indicator so you can be aware of a possible internal issue. Flying with no gas, no oil, no landing wheels or a defective lithium battery can result in a problem. The BMS is not a limitless protective device and does have limitations. The weakest link in the charging system is the REGULATOR which is rarely discussed. When your regulator fails, you can easily see voltages climb to levels that will destroy your expensive electronics and damage your battery. Whether it is lead acid or lithium, it is the recipient of the high voltage and huge amounts of current from your alternator. For example, if your voltage is 24V, and you have a 60 amp alternator, you can see 1320 Watts! (24V X 55 amp = 1320 Watts). That is more heat than many microwaves put out. This type of heat will cause a lead acid battery to heat to the point of exploding and spray hot acid and if a lithium battery, with no protection such as the Aerovoltz that started this thread of discussion, receives it the cells rupture, it can and will most likely melt the plastic casing, and the very heated electrolyte will cause a lot of smoke for about 10-15 minutes. The video of this happening was provided with this thread. Smoke is dangerous, we are not saying it is not but the fear of "exploding and fire" is just that, a fear. The video shows the extent of what happens in a catastrophic failure- a lot of smoke, the case can melt, and then after about 10-15 minutes of smoke, it's done. No explosion, no fire. When you are in flight, if your voltage reading is above 15.1V, you need to immediately take your alternator off line to avoid the above scenarios. Ideally, you will have overvoltage protection on your regulator (crowbar) that takes the human factor out and will automatically do this.
Sorry for the length of the response but we wanted to convey, safety is our first and primary mission for the EarthX batteries and we will continue to dedicate the company resources towards providing products geared to this mission. But as for all products, there are limits to what they can do and it is your responsibility to understand the products you are using and use the guidelines and warnings the manufacturer provides with that product.
As always, please know we are here to assist you and answer questions. There is no dumb question! If in doubt, call. 1 (970) 674-8884 or email at [email protected]
Good Morning Van's forum,
Thank you for those who contacted me to let me know about this thread. I will admit, I do not monitor it enough so please know you can ALWAYS contact us for questions or concerns, we are here to assist you.
Couple of quick answers to questions:
1- How do you ship the battery back? In the event you have a possible problem and have an illuminated light, we send you a replacement battery in a ground shipment box that is labeled correctly for shipping a lithium battery and inside is the prepaid return label. All you do is remove new, put in "old" and it comes back to us. A blinking light or a solid light does not mean it is a shipping hazard.
2- What does the blinking or solid light alert you to? I am going to copy and paste from the manual on the aircraft batteries and there is also a checklist chart that will come with your battery but can also be found in the manual a well:
ETX Hundred Series - BMS
The ETX ?Hundred Series? was specifically designed for the experimental aircraft market (models include the ETX680C, ETX680, ETX900, ETX1200). Only the ETX ?Hundred Series? battery models are recommended for use as the primary aircraft battery (starter battery). In addition to the features found in the ETZ and ETX series motorsports batteries, critical electronic circuits are redundant, the over-charge protection is enhanced and fault indication is included.
All components associated with main electronic battery disconnect are redundant. The built-in redundancy ensures that no single point failure results in the battery unintentionally disconnecting. The design aligns with the requirements for a FAA approved lithium battery as per RTCA performance specification DO-311.
In the event of a charging system failure where the voltage increases to above 15.2V, the resistance to charging current increases, and above 16V the charging current is completely blocked. This design offers charge voltage protection greater than 40V. The discharge current (current out of battery) is unaffected in this situation.
The battery?s micro-controller monitors all failure modes, and reports failures with a built-in LED indicator and discrete output. The discrete output for external fault monitoring is a single wire connection with ?? quick connect terminal. The output is a ?current sinking? type circuit (see diagram below) that can handle 100mA (connects the discrete output to battery ground if a fault is present). This output can be connected to an external 12V LED or general purpose discrete input of an EFIS. The fault output has two states; slow flashing (5 second cycle time) or solid.
The slow flashing fault can indicate an improper state of charge or a problem with the cells internal to the battery. If the battery voltage is outside the normal range of operation, 12.8V to 14.6V, the battery is over-discharged or over-charged, most likely the result of an issue with the electrical/charging system. If the battery voltage is within the normal operating range, with a slow flashing fault, it is indicating an abnormal condition with a cell, such as one cell?s state of charge is very different as compared to the other cells (high cell charge level imbalance). The slow flashing fault may come on briefly during or following periods of high current charging, and is not a concern. But if the fault persist, comes on consistently during changing, or remains (charging or not), the battery will need to be replaced.
The solid fault indicates a BMS hardware failure. For example, if the micro-controller fails the fault indication output is activated (on solid). If the fault persist, comes on and stays on, the battery will need to be replaced.
3- Fear. We at EarthX have dedicated ourselves to the experimental aircraft market to provide a safe product and continuously research and implement features to reflect this. We attend many aircraft tradeshows and present in their forums to educate and provide an opportunity to ask questions too. We have had the opportunity to work with many aircraft manufacturers and engine manufacturers to integrate the most robust, safe, lithium battery option for our users on the market today. We have added the remote LED fault light indicator so you can be aware of a possible internal issue. Flying with no gas, no oil, no landing wheels or a defective lithium battery can result in a problem. The BMS is not a limitless protective device and does have limitations. The weakest link in the charging system is the REGULATOR which is rarely discussed. When your regulator fails, you can easily see voltages climb to levels that will destroy your expensive electronics and damage your battery. Whether it is lead acid or lithium, it is the recipient of the high voltage and huge amounts of current from your alternator. For example, if your voltage is 24V, and you have a 60 amp alternator, you can see 1320 Watts! (24V X 55 amp = 1320 Watts). That is more heat than many microwaves put out. This type of heat will cause a lead acid battery to heat to the point of exploding and spray hot acid and if a lithium battery, with no protection such as the Aerovoltz that started this thread of discussion, receives it the cells rupture, it can and will most likely melt the plastic casing, and the very heated electrolyte will cause a lot of smoke for about 10-15 minutes. The video of this happening was provided with this thread. Smoke is dangerous, we are not saying it is not but the fear of "exploding and fire" is just that, a fear. The video shows the extent of what happens in a catastrophic failure- a lot of smoke, the case can melt, and then after about 10-15 minutes of smoke, it's done. No explosion, no fire. When you are in flight, if your voltage reading is above 15.1V, you need to immediately take your alternator off line to avoid the above scenarios. Ideally, you will have overvoltage protection on your regulator (crowbar) that takes the human factor out and will automatically do this.
Sorry for the length of the response but we wanted to convey, safety is our first and primary mission for the EarthX batteries and we will continue to dedicate the company resources towards providing products geared to this mission. But as for all products, there are limits to what they can do and it is your responsibility to understand the products you are using and use the guidelines and warnings the manufacturer provides with that product.
As always, please know we are here to assist you and answer questions. There is no dumb question! If in doubt, call. 1 (970) 674-8884 or email at [email protected]
ppilotmike
Well Known Member
Thanks Kathy..
..for addressing the concerns stated in previous posts. Now that you are a VAF advertiser, I would strongly recommend checking into the site regularly, even if it's not every day, for just this reason. The experimental aviation community needs to be educated about this technology, if we're ever going to adopt it into our aircraft.
Thanks to the press and posts from those who have had negative experiences, we all know there are dangers that exist within this technology. What we need to understand better is: how are those dangers being addressed, controlled and/or removed from the equation. We also know that there are different battery chemistries and that each company making these batteries chooses their own path to a viable and sellable product.
We need to know if there is a product out there that is truly viable for experimental aviation, and, if so, how it is safer than the ones we hear about in the press. I personally believe your product may be the one, but I want to learn more, and I think most of us would say the same.
As President of EAA Chapter 301, I look forward to your presentation to our Chapter on March 17th. We have a lot of members who are intrigued but want to know more. I think it will be a great program.
To others who want to learn more about EarthX, I would urge you to talk to them, via phone, VAF posts, emails or in person at Airventure 2017, if you're going to be there. They are good people and, IMHO, sincerely want to create a safe, viable product for us.
..for addressing the concerns stated in previous posts. Now that you are a VAF advertiser, I would strongly recommend checking into the site regularly, even if it's not every day, for just this reason. The experimental aviation community needs to be educated about this technology, if we're ever going to adopt it into our aircraft.
Thanks to the press and posts from those who have had negative experiences, we all know there are dangers that exist within this technology. What we need to understand better is: how are those dangers being addressed, controlled and/or removed from the equation. We also know that there are different battery chemistries and that each company making these batteries chooses their own path to a viable and sellable product.
We need to know if there is a product out there that is truly viable for experimental aviation, and, if so, how it is safer than the ones we hear about in the press. I personally believe your product may be the one, but I want to learn more, and I think most of us would say the same.
As President of EAA Chapter 301, I look forward to your presentation to our Chapter on March 17th. We have a lot of members who are intrigued but want to know more. I think it will be a great program.
To others who want to learn more about EarthX, I would urge you to talk to them, via phone, VAF posts, emails or in person at Airventure 2017, if you're going to be there. They are good people and, IMHO, sincerely want to create a safe, viable product for us.
RVbySDI
Well Known Member
Hello Mike,
Question concerning your Chapter 301 meeting. I had initially read your post thinking: "Hmmm, it might be fun to fly out to Denver and attend your meeting. Then I saw that the 17th is on Friday. So do you have an evening meeting on Friday then? I have flown with the EarthX for about a year now and thought I could spend a Saturday flying out and visiting a new EAA chapter but not so sure it is doable for a Friday meeting. I would love to attend this meeting and listen to Kathy's presentation though. It ought to be informative.
Thanks Mike and we are looking forward to coming to your EAA meeting.
We understand that the word "lithium" makes head lines news and is a buzz word that gets people talking. Most of the head line news is about Lithium Cobalt chemistries found in the Samsung phones currently in the news, laptops, hoover boards and many portable jump packs, not lithium iron phosphate (LiFePo4).
If the battery is a starter battery, the only chemistry used is LiFePo4 as this is the only one compatible with the vehicles charging system due to their voltage range. A lithium cobalt, depending on how many in series, is either 11.1V or 14.8V. Either too low of voltage or too high and your alternator would either over charge it or wouldn't be able to charge it. That is one of the reasons why you can't use your cell phone battery to start your plane.
As far as the experimental market adopting this technology, many already have. We work with Rotax Engines, Continental Engines, Viking Engines, UL Power Engines, Sonex Aircraft, Kitfox Aircraft, Viking Aircraft, Glasair Aviation Aircraft, EuroFOX Aviation, Powrachute, Revo, STOLquest, Evolution Aircraft, Mosquito Helicopters, Back Country Cubs, Ion Aircraft, Murphy Aircraft, plus many more.
As with all products, there is a range of quality and features and not all lithium batteries are created equal. The reason for our success with the above aircraft manufacturers and a customer base in the thousands is the safety features and innovative technology found in the EarthX brand.
We do have a lot of Fact Sheets to provide information on the website www.earthxbatteries.com under the documentation tab for those looking for detailed technical information, an extensive manual and we are also working on providing technical letters to our users and also a power point presentation too so you have many ways of accessing information.
FYI; here is a great product for the over voltage protection I mentioned in the previous post: http://www.bandc.aero/over-voltageprotectionmodule.aspx that only costs $40 but could save you thousands in damaged electronics.
ppilotmike
Well Known Member
Steve,
We meet on the third Friday of each month, at 7PM. You can find more information on our website http://www.eaa301.org/,
Kathy, you mentioned the crowbar sold by B&C. Their site says this is the same module they include in the B&C regulators, which cut off at 16.0V according to the installation manual.
In an earlier post you said, "if your voltage reading is above 15.1V, you need to immediately take your alternator off line to avoid the above scenarios."
Can you tell us if the battery releases its magic smoke when the voltage regulator fails and the output is, say, 15.8V, which would not be enough to activate the crowbar, but I continue flying blissfully unaware for another hour?
Thanks for responding to all the questions.
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Dear Kurt,
The crowbar or overvoltage protection for your regulator is not always a standard option and does not come with all regulators. The one I mentioned was for those who do not have one.
In the regulator manuals, at least all that we have checked to verify this information, state that if you have a voltage of 15.1V, this is outside of the upper range that the regulator should be performing at and to replace it. If the regulator has failed, the voltage will continue to climb above this number and can so rather quickly. The statement of "if your voltage reading is above 15.1V, you need to immediately take your alternator off line to avoid the above scenarios" is a call to action.
Which leads to your next question "Can you tell us if the battery releases its magic smoke when the voltage regulator fails and the output is, say, 15.8V, which would not be enough to activate the crowbar, but I continue flying blissfully unaware for another hour? In this scenario, a couple things would happen.
First, if your regulator failed, you would not see a steady reading of the 15.8V but instead a steady climb of voltage readings.
Second, you should have a high voltage indicator either through your EFIS or a voltage gauge that warns you of this over voltage situation.
Third, if you have connected the LED light safety feature on the EarthX battery, you would also have a flashing warning light to alert you of an over voltage attempt at the battery.
Fourth, if you did not notice any of these warnings and continue to fly blissfully for another hour, the EarthX battery itself has over voltage protection and will block the excess voltage coming into the battery.
Not trying to be harsh here, but as a pilot, it is your responsibility to watch your gauges and be alert of warnings and not depend upon your equipment for your safety but instead on your intellect to fly the plane. The "magic smoke" you refer to has no exact calculations but when we disable the BMS, use defective cells, put 24V and 55 amps through the battery, it takes about 10 minutes to rupture the cells approximately.
BillL
Well Known Member
The regulator is always discussed in relation to the LiFeP battery.
1) Lets hit the second item first - I bring up the regulator every time. And the fact that normal voltage limiters, crowbars, don't trigger until about 16.7 volts. (correction: 16.3 +.3v according to Aeroelectric) This has always appeared to be the highest potential for trouble.
2) BMS triggering at 15.2v and severing at 16 v. : Maybe this is now on your website and manual, but I have not seen it discussed there. After starting, all electrical systems are drawing all the current from the alternator, it is the sole source unless there is a disruption. So, if I understand, the battery is disconnected completely, and no buffering of the buss (bus?) voltage is now taking place. Interesting that you can still provide current, but not accept current. Not sure that is important, so lets leave that alone unless you think it is relevant. What is important is the "resistance is increased" what does that mean, will the alternator amperage draw increase due to battery resistance?
3) Overall, it seems EarthX is now recommending that a crowbar be employed and that it be set at 15.2 volts? Is that right? In the EarthX back room during technical considerations: what is the expected variance (tolerance) of a standard regulator and what is the variance (tolerance) of the trigger voltage of the crowbar? We know some regulators yield as high as 14.7 VDC nominal leaving little room for a crowbar trigger point.
Maybe some electrical types can help with the expected variables here to understand if this is practical. B&C certainly makes an adjustable regulator, but the voltage tolerance over the load range is not readily available. And, surely the standard crowbar can be modified to trigger at 15.2 VDC. The question is the possibility of nuisance triggers due to transient spikes.
It sure looks like we are changing the standard electrical system to address a potential battery failure mode. Not a bad thing, but it is painful identifying the requirements. Exactly what are the requirements for nominal voltage and crowbar trigger? Please include tolerances.
1) Lets hit the second item first - I bring up the regulator every time. And the fact that normal voltage limiters, crowbars, don't trigger until about 16.7 volts. (correction: 16.3 +.3v according to Aeroelectric) This has always appeared to be the highest potential for trouble.
2) BMS triggering at 15.2v and severing at 16 v. : Maybe this is now on your website and manual, but I have not seen it discussed there. After starting, all electrical systems are drawing all the current from the alternator, it is the sole source unless there is a disruption. So, if I understand, the battery is disconnected completely, and no buffering of the buss (bus?) voltage is now taking place. Interesting that you can still provide current, but not accept current. Not sure that is important, so lets leave that alone unless you think it is relevant. What is important is the "resistance is increased" what does that mean, will the alternator amperage draw increase due to battery resistance?
3) Overall, it seems EarthX is now recommending that a crowbar be employed and that it be set at 15.2 volts? Is that right? In the EarthX back room during technical considerations: what is the expected variance (tolerance) of a standard regulator and what is the variance (tolerance) of the trigger voltage of the crowbar? We know some regulators yield as high as 14.7 VDC nominal leaving little room for a crowbar trigger point.
Maybe some electrical types can help with the expected variables here to understand if this is practical. B&C certainly makes an adjustable regulator, but the voltage tolerance over the load range is not readily available. And, surely the standard crowbar can be modified to trigger at 15.2 VDC. The question is the possibility of nuisance triggers due to transient spikes.
It sure looks like we are changing the standard electrical system to address a potential battery failure mode. Not a bad thing, but it is painful identifying the requirements. Exactly what are the requirements for nominal voltage and crowbar trigger? Please include tolerances.
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Dear Bill,
Thank you for your questions. When a regulator fails, the voltage will climb quickly and be beyond the discussed voltages (15.1V-16.7V) in seconds, even milliseconds. It is not a steady voltage reading as it is not ?regulated? any more. If you have a crowbar protection circuit, it engages very quickly and automatically. You do not need to wait for the pilot to recognize the issue and then react. Having crowbar protection is wise for any plane to have, no matter what battery they are using. I personally would not use a lithium battery that has no BMS protection nor would I have a regulator that does not have crowbar protection as I would not be comfortable with this level of equipment failure backup, I like redundancy.
And to clarify this situation, this is when your regulator has failed and the voltage is left unchecked and climbing. This is not when you have transient spikes, a crowbar will not be triggered for this nor is the BMS protection inside the battery. These are normal and expected spikes. The protection comes into play when the voltage remains at a high level and is still rising.
Thank you for your questions. When a regulator fails, the voltage will climb quickly and be beyond the discussed voltages (15.1V-16.7V) in seconds, even milliseconds. It is not a steady voltage reading as it is not ?regulated? any more. If you have a crowbar protection circuit, it engages very quickly and automatically. You do not need to wait for the pilot to recognize the issue and then react. Having crowbar protection is wise for any plane to have, no matter what battery they are using. I personally would not use a lithium battery that has no BMS protection nor would I have a regulator that does not have crowbar protection as I would not be comfortable with this level of equipment failure backup, I like redundancy.
And to clarify this situation, this is when your regulator has failed and the voltage is left unchecked and climbing. This is not when you have transient spikes, a crowbar will not be triggered for this nor is the BMS protection inside the battery. These are normal and expected spikes. The protection comes into play when the voltage remains at a high level and is still rising.
snopercod
Well Known Member
New shipping/training regs for Li batteries are on hold
Kathy-- You probably already know about this but the new regs on the shipping of Lithium batteries requiring new labels and employee training are on hold. See: http://blog.labelmaster.com/trump-freezes-phmsa-hm-215n-the-impact-on-lithium-battery-shippers/ Cheers!
Kathy-- You probably already know about this but the new regs on the shipping of Lithium batteries requiring new labels and employee training are on hold. See: http://blog.labelmaster.com/trump-freezes-phmsa-hm-215n-the-impact-on-lithium-battery-shippers/ Cheers!
BillL
Well Known Member
I am sure failure modes of a regulator (lets call it bus voltage regulation) are not limited to one that simply allows a rapid increase in voltage. Our RV's use a separate "sense" wire for the voltage and there are other failure modes that result in a steady regulated, but elevated, voltage. This failure mode has been reported here on VAF many times, and seems to be at least as likely as the instant increase. Hard to draw a conclusion on probability of these failure modes with anecdotal data.
Back to the question(s). Does the "resistance" created above 15.2 volts by the BMS increase the current demand on the alternator? Where does the energy go?
Does EarthX only use available industry test standards or do you develop appropriate abuse and accelerated aging tests for the general aviation aircraft based on their operational profiles and the potential failure modes of this specific technology? Have you run the OSH departure test yet?
You said that 24 volts was put to a defective cell and it induced a thermal runaway in 10 min. Can 16.7 volts do that under the same conditions? If not, we can celebrate!
BTW - operation IFR requires an extra hour of fuel to reach an alternate. That would not be a blissful hour in IMC with a seriously unhappy EarthX battery. The one hour situation is not unlikely or trivial, so it should be considered. If the product can not do this, it should be so stated to allow mitigation or avoidance.
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N941WR
Legacy Member
Maybe there is some good news coming:
https://news.utexas.edu/2017/02/28/goodenough-introduces-new-battery-technology
https://news.utexas.edu/2017/02/28/goodenough-introduces-new-battery-technology
BillL
Well Known Member
Good news usually does not arrive very fast. I found articles on hybrid cars in the 1968 Popular Mechanics mag. GM and Ford were first but abandoned them. Jimmy Carter era spawned a renewed effort for hybrid vehicles. USCAR, the battery consortium was founded in 1991.
The pipeline for new technology to overtake current stuff is much much longer than we typically think. The "2-yr and obsolete" marketing lines are just at the spigot. DOE put $400+ million into A123 batteries using LiFePO technologies. Founded in 2001.
It has taken a long time to even begin to become competitive in the aero market and this thread says that is still being sorted for matching the product characteristics to the application parameters to yield a robust, mature product.
Kudos to EarthX for leading the way, that is why they catch the flak.
That's good news for lithium ion battery users....but not applicable to this thread. The OP and EarthX batteries are Lithium Iron Phosphate, a completely different (and safer) chemistry.
As Paul Dye said in a different thread, part of the key to calming much of the panic about "lithium" batteries (as a general category) involves understanding specific properties and history behind the specific TYPES of Lithium batteries.
Lithium Ion: bad. Those are the types we see exploding into flames in e-cigs, iPhones, etc.
Lithium Iron Phosphate (LiFePO): Good. EarthX batteries are LiFePO, and ever safer with the redundant Battery Management System (BMS) that Kathy discussed below. The battery discussed in the OP has no BMS.
Here here! LiFePO batteries are good for aviation, if done right. EarthX is getting it right, all the while leading from the front. I love my ETX900.
Alan Carroll
Well Known Member
Unfortunately I think the reality is a lot more complicated than this, and the terminology can certainly be confusing. Here's what I've pieced together so far (note: I could be wrong so please take this with a grain of lithium!):
Every battery with the word "lithium" in the name is in fact a "lithium ion" battery. They're all based on the principal that lithium ions (Li+) move from the cathode (negative electrode) to the anode (positive electrode) during discharge.
There are many different chemistries of lithium ion batteries, of which LiFePo (lithium iron phosphate) is one. Both the EarthX and the Aerovoltz are LiFePo. LiFePo is characterized by relatively low energy density but better stability than some other chemistries. The batteries in RC models, UAVs, etc. are generally LiCoO2 (lithium cobalt dioxide), I think. I'm not sure what Samsung uses.
Lithium Polymer (LiPo) is a construction technique that uses a porous polymer sheet to separate the anode and cathode sheets. It can be used with a variety of different battery chemistries, and allows for faster discharge rate. The same name is also applied to a technology that uses a polymer electrolyte, but apparently this technology has not been widely commercialized yet.
Finally things like the physical design of the battery, manufacturing defects, battery management systems (BMS), and operating practices can affect the safety of any of these batteries. This I think is where companies like EarthX have a lot to offer.
Bill Boyd
Well Known Member
A lot to think about
and decision time for some of us is already here as we build along.
I'm pretty sure an EarthX will be in my aircraft - whether in the conventional tail location with some CCA Fatwire, or ahead of the firewall - but that somebeach will be inside a stainless enclosure vented overboard, in my current thinking
and decision time for some of us is already here as we build along.
I'm pretty sure an EarthX will be in my aircraft - whether in the conventional tail location with some CCA Fatwire, or ahead of the firewall - but that somebeach will be inside a stainless enclosure vented overboard, in my current thinking
Have there been some updates to EarthX batteries since the first models came out?
I see several posters here had the light come on and returned their batteries for new ones. While it's great that EarthX stands behind their products with good service, how many people have had to return them after the warning lights came on?
Question to EarthX, what is the major reason people have returned batteries and what is the fix? Has the fix been implemented in the latest designs?
I see several posters here had the light come on and returned their batteries for new ones. While it's great that EarthX stands behind their products with good service, how many people have had to return them after the warning lights came on?
Question to EarthX, what is the major reason people have returned batteries and what is the fix? Has the fix been implemented in the latest designs?
Reformed SeaSnake
Active Member
Long time lurker here, finally paid the dues and since I have been looking at EarthX batteries for my build I'll throw in what I've learned:
Alan, you are correct. All currently available Lithium-based batteries are Lithium Ion. This includes currently available Lithium Polymer (LiPo) batteries. though Ionic Materials has produced a working LiPo battery that does not rely on any liquid electrolyte, their product is not yet available commercially. This battery was featured on a recent NOVA episode.
For anyone wanting to learn more about the chemistry of Lithium battery thermal runaway, the Royal Society of Chemistry has an interesting and pretty readable article here:
Thermal-runaway experiments on consumer Li-ion
batteries with metal-oxide and olivin-type
cathodes
I confess, I was a chemical engineer in a former life so my definition of "interesting" and "readable" may be skewed, however, there were a couple interesting takeaways:
1) All Lithium batteries can experience thermal runaway, either if they are overcharged or if they are subjected to high temperatures
2) LiFePO4 batteries are the safest of the current Lithium Ion batteries in the following ways
a) They require the highest temperature (~195 C) to initiate thermal runaway.
b) They evolve the least gas over the longest period of time (about 1/5 as much gas as Cobalt containing batteries)
c) The maximum temperature in thermal runaway is lower than for other Lithium battery chemistries (~400 C vs over 900 C for Cobalt containing batteries).
3) The gas evolved from all Lithium-based batteries contains a number of flammable constituents including Hydrogen as well as CO (not easily flammable, but dangerous).
4) maximum temperature during thermal runaway in LiFePO4 batteries is lower than the auto-ignition temperature of the evolved gas (~500-550 C), However, the maximum temperature of the common Cobalt containing batteries is well above the auto-ignition temperature of the gas. Hence, the much cooler YouTube videos with Lithium-Cobalt batteries.
All of that said, I am personally comfortable installing an EarthX battery in my airplane, either forward of the firewall or aft of the aft baggage bulkhead in a well-ventilated tail.
Alan, you are correct. All currently available Lithium-based batteries are Lithium Ion. This includes currently available Lithium Polymer (LiPo) batteries. though Ionic Materials has produced a working LiPo battery that does not rely on any liquid electrolyte, their product is not yet available commercially. This battery was featured on a recent NOVA episode.
For anyone wanting to learn more about the chemistry of Lithium battery thermal runaway, the Royal Society of Chemistry has an interesting and pretty readable article here:
Thermal-runaway experiments on consumer Li-ion
batteries with metal-oxide and olivin-type
cathodes
I confess, I was a chemical engineer in a former life so my definition of "interesting" and "readable" may be skewed, however, there were a couple interesting takeaways:
1) All Lithium batteries can experience thermal runaway, either if they are overcharged or if they are subjected to high temperatures
2) LiFePO4 batteries are the safest of the current Lithium Ion batteries in the following ways
a) They require the highest temperature (~195 C) to initiate thermal runaway.
b) They evolve the least gas over the longest period of time (about 1/5 as much gas as Cobalt containing batteries)
c) The maximum temperature in thermal runaway is lower than for other Lithium battery chemistries (~400 C vs over 900 C for Cobalt containing batteries).
3) The gas evolved from all Lithium-based batteries contains a number of flammable constituents including Hydrogen as well as CO (not easily flammable, but dangerous).
4) maximum temperature during thermal runaway in LiFePO4 batteries is lower than the auto-ignition temperature of the evolved gas (~500-550 C), However, the maximum temperature of the common Cobalt containing batteries is well above the auto-ignition temperature of the gas. Hence, the much cooler YouTube videos with Lithium-Cobalt batteries.
All of that said, I am personally comfortable installing an EarthX battery in my airplane, either forward of the firewall or aft of the aft baggage bulkhead in a well-ventilated tail.
