BruceMe

BruceMe

Well Known Member
I found some old threads on Lithium batteries. But I wanted a follow-up. Are they still working and safe?

Thanks,

-Bruce
RV-4 254MM
#2208 bought in 1997, first flight 2008, finished 2015
 
I am not yet there but plan to use the EarthX batteries (primary/backup). Two of their 680s are lighter than one standard gel cell.
 
29 hours troublefree so far on a Shorai 18ah. Looking forward to some cold weather starts soon.

Bevan
 
Good so far

I have a Shorai LFX18L1-BS12 it’s 6AH (actual) weighs about 2 lb and it’s 18 months old with 100 flight hours(all in the last 6 months). I use it to back up the AV buss, I have the standard PC680 for the main battery. The Shorai automatically feeds the AV buss if the main voltage drops below 13.8 volts. I keep it charged using a B&C SD-8 alternator with OV protection. I’m happy so far with its performance, I’ll be very happy if it last 5 years so we’ll see. It does not have under voltage protection so all it takes is one time bring it below 10 volts or so and I’m buying another one. My avionics stay on as long as the backup master is on so hopefully that’s enough of a reminder but time will tell. I’ve considered putting in my own under voltage protection and I may do that in the future. I do charge it with a balancing charger every few months to keep the cells balanced some have that built in which is nice, but it does cost more. This one cost me $130 a year and half ago so if I lose it I won’t feel too bad. I have a cross connect option that allows me to use the Shorai to start the engine and that works very well, it has plenty of starting power.
 
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Great, I have a lot of good experience with LiFePO4 from an DIY electric vehicle conversion I upgraded and drove for years. From that experience, I know they drop off rapidly in current capability below about 50F and drawing current below 2v/cell does permanent irrevocable damage. Otherwise they proved very robust and produce dramatically better in all regards than SLA for a fraction the weight. And I know they have a nice low self-discharge another nice long winter months feature.

Would still love to hear from someone who has had it longer than a few months.

Thanks though!
 
+1 EarthX Batteries

I too, believe that EarthX is on the right track. They are really pushing to develop their aircraft batteries to be safe and reliable for use in experimental aviation. They have also been very open to discuss & educate experimental guys like us on topics such as Amp Hours, Cold Cranking abilities and others. I have one of their batteries in my motorcycle now. Maybe when the time comes, I'll put one in the plane too..
 
Bought the EarthX, never worked from the start (read would not turn engine at all). I even bought the Optima4 charger for it. For now I traded back to Concorde. I will call EarthX up soon.
 
Evolution10 said:
Bought the EarthX, never worked from the start (read would not turn engine at all). I even bought the Optima4 charger for it. For now I traded back to Concorde. I will call EarthX up soon.
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I've got the EarthX 36, and it turns my IO540 like crazy... and I think the 10 is the worst case scenario. Long battery cables with the battery in the tailcone, and a 6 cylinder engine.

I've only had to start down to 27 degrees so far, but no change in the cranking performance in those conditions.
 
I was going to use an Odyssey PC680 in our project plane, and I even bought a pair of them for this very purpose. Then the battery in my wife's Miata failed, so one of the 680's was called into service. Uh oh, now the lawn tractor won't start. Dang, there goes the second 680.

Now that I have no 680's in stock, I'm giving consideration to going the EarthX route.

What I'd like to know is how large is the install base and what is the fleet flight hour accumulation on these LiFePo batteries. In short, I'd like to get a sense of overall reliability. A second important consideration for me is, being a Canuck, I have to have a battery that will make things go when it's cold. I mean cold, as in -20C (my personal cutoff for flying).
 
Canadian_JOY said:
I was going to use an Odyssey PC680 in our project plane, and I even bought a pair of them for this very purpose. Then the battery in my wife's Miata failed, so one of the 680's was called into service. Uh oh, now the lawn tractor won't start. Dang, there goes the second 680.

Now that I have no 680's in stock, I'm giving consideration to going the EarthX route.

What I'd like to know is how large is the install base and what is the fleet flight hour accumulation on these LiFePo batteries. In short, I'd like to get a sense of overall reliability. A second important consideration for me is, being a Canuck, I have to have a battery that will make things go when it's cold. I mean cold, as in -20C (my personal cutoff for flying).
Click to expand...

Call EarthX and ask for Kathy. She will give you answers or go and get answers for you.
 
Guilhermepilot said:
Ask guys at Boeing 787! fire, fire, heat. dangerous, it is not worth
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The 787 uses a LiCoO2 battery the only technology available at the time, the newer LiFePO4 are much safer and what is in use today. They're used in electric cars as well as laptops etc. For me the weight savings plus other advantages are hard to ignore.
 
Evolution10 said:
Bought the EarthX, never worked from the start (read would not turn engine at all). I even bought the Optima4 charger for it. For now I traded back to Concorde. I will call EarthX up soon.
Click to expand...

Could have a bad cell, which would indicate proper Volts, but might hamper cranking ability. Call them up, I'm sure they can help diagnose the problem. If it was bad from the start they'd probably replace it.
 
BruceMe said:
Great, I have a lot of good experience with LiFePO4 from an DIY electric vehicle conversion I upgraded and drove for years. From that experience, I know they drop off rapidly in current capability below about 50F and drawing current below 2v/cell does permanent irrevocable damage. Otherwise they proved very robust and produce dramatically better in all regards than SLA for a fraction the weight. And I know they have a nice low self-discharge another nice long winter months feature.

Would still love to hear from someone who has had it longer than a few months.

Thanks though!
Click to expand...

Close to two years, 370+ hours, and zero problems on the Shorai battery. Very happy with it and would do it again without pause.
 
I don''t think anyone will disagree at this point, that any lithium battery chemistry can fail in a mode that results in the battery emitting copious amounts of noxious smoke and or fire. Even for Lithium Iron phosphate chemistries, a battery management system is necessary. For example, over discharging any single cell can induce failure on recharge sometime in the future. Lithium cells don''t tolerate over discharge at all.

I just reconfirmed via email from Shorai, that they do not have a BMS to protect from over discharge, over voltage, overtemperature or provide cell balancing. There are batteries out there that do. EarthX actually has robust BMS with some integrated redundancies. At least this system has a reasonable chance of preventing battery misues/abuse resulting in premature failures. Failures don't always mean fire and smoke, but often do.

I have driven certified batteries to failure during TSO testing (including LiFePo batteries), and you would not want to have this happening anywhere where the fumes or fire could get in the cockpit.

http://www.vansairforce.com/community/showthread.php?t=120338&highlight=shorai+battery+fire

This thread discusses what ended up being an overvoltage related fire on a battery with no BMS.

The risk is yours to take, or not, but you should understand that there is a better option.
 
RVDan said:
The risk is yours to take, or not, but you should understand that there is a better option.
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Which is what, Dan? Lead acid?

(Not a leading or laoded question. You seem to speak from experience but not sure what you were meaning here.)
 
I think it's unfair to condemn all Lithium batteries because a few have failed. There many millions of Lithium batteries in use everyday without one problem. Lithium chemistry has been for a very long time. I can't remember the first time I saw a 3 volt battery in a PC, in the '80's. Lithium. Lead acid fails, NiCad fails, NiMH fails, Alkaline fails. I have a few friends using Lithiums in their planes without problems. When my PC680 slides into the afterlife I'll get a Lithium. They are in **** near everything nowadays.
 
RVDan said:
The risk is yours to take, or not, but you should understand that there is a better option.
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That's pretty subjective. Certainly not better in terms of cost, or weight. And with an EMS providing over-voltage warning coupled with some form of automatic over-voltage protection, along with regular cell balancing (I do it when I change the oil) there is little need for a BMS to prevent an over-voltage condition.
 
krw5927 said:
Which is what, Dan? Lead acid?

(Not a leading or laoded question. You seem to speak from experience but not sure what you were meaning here.)
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Sorry didn't mean to be vague. I only said that because as experimenters we want to make risk decisions based on the money we trade to reduce risk. So I meant the risk posed by Lion batteries. You can choose the cheaper Lion batteries without BMS's and take your chances or buy one with a BMS and be "safer". The risk can be quantified very easily. A battery model with no BMS will have greater chance of failure with smoke and fire than a battery with one.

In the certified airplane world in addition to a BMS of a numerically quantified reliability, we are also required to have an enclosure that will contain and vent the smoke and fire overboard in case the battery fails that way. That is safe.

Responding to FASGLAS. I am not trashing the technology, just stating that there are known failure modes that lead to smoke and fire for all of th eLion chemistries. Some of these are user induced, like discharging the battery below the minimum voltage for the cells, another is high temperature environments, another is over voltage charging, and some are cell manufacturing related. I think there might be some science guys who could talk more to that, but the industry says that about 1 in 3 million cells will contain a defect that will cause the cell to fail by overheating. That number is about 3 yrs old, and not very well quantified by industry, since no one reports cell failures from the field, but that is their best guess. The simple addition of a BMS will go a long way to reducing all types of failures and given the sensitivity of the flight environment to fire or smoke, a good thing.

BTW, even the small cylindrical cells sold for your flashlight contain rudimentary bMS's. If you try to buy a raw cell without a BMS the cell manufaturer usually provides a statement that you must provide a BMS.
 
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