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Earthx batteries

The VAF Search is your friend

Henke,
I ran a VAF search on EarthX for you (link below).

http://www.vansairforce.com/community/search.php?searchid=32829252

Simply put, EarthX batteries' performance and durability are outstanding, as are their safety and the company's customer support. If Kathy or a 540/EarthX user don't chime in here soon, I'd just visit their website and email them.

Remember, though, that you need to match the battery to the alternator's amperage, not the engine. For example, of you use the Odyssey 680 battery, you want an EarthX ETX680. I have a 70 amp alternator, which makes the ETX680 too small: Thus, I fly an ETX900.

Of note, with my airplane on a flat surface, no wind, engine off, no chocks, throttle idle/mixture cutoff: If I crank the prop for 10 seconds, that battery has me taxiing forward at 2 knots groundspeed! I love the EarthX battery. :cool:
 
Seems a number have been replaced in the first year under warranty for cell imbalance warnings. When I asked the question here on VAF (how many and why), a month or 2 ago, it went unanswered. Good to step up and replace product which doesn't meet specs but why have we seen reports of several here being replaced within months of purchase? Is this just extra caution on the part of EarthX for the aviation environment?
 
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Without actually answering on EarthX's behalf, but based solely on my own observations, I believe it's a two-fold 'yes'.

Over the past 2 years, EarthX had been improving their product, including the cell balancing and the battery management circuits' tracking and identification of cell problems.

In addition, they've been very aggressive in immediately replacing such batteries. They want the old battery back because it's a data point that helps them improve the product. At Oshkosh, Kathy told me their return rates have dropped as they have improved the product.

Me? Clearly I'm a fan of the battery.
 
I just replaced my Pc680 with an Earthx and while I can't vouch for longevity, I can vouch for the weight savings and the extra cranking amps...the thing really spins my IOX-370 at start. So far very pleased. It's hard to imagine that much energy out of something so small and light
 
ETX900

I have been flying behind an ETX900 since February 2016. Promptly replaced when I called about a cell imbalance warning. No issues since then.

Not only does this battery spin the prop faster than anything I have seen, it also recharges just as fast. After a prolonged hot start, I have seen 60+ amps for a minute before it declines to my normal 17 amp draw.

I'm a fan.
 
I've had a 1200 in my own RV-10 and a couple of 900's in others for over a year with no issues.

Vic
 
Seems a number have been replaced in the first year under warranty for cell imbalance warnings. When I asked the question here on VAF (how many and why), a month or 2 ago, it went unanswered. Good to step up and replace product which doesn't meet specs but why have we seen reports of several here being replaced within months of purchase? Is this just extra caution on the part of EarthX for the aviation environment?

Dear Ross,

The original software algorithm in 2015 for detecting cell imbalances was too conservative and was giving false warnings. Our primary focus is safety and performance and when we received these batteries back, there was nothing wrong with the cells but that is how we determined the software was too conservative. I am sure it was an inconvenience to these battery owners, but we would rather be on the side of caution than not.
 
Dear Ross,

The original software algorithm in 2015 for detecting cell imbalances was too conservative and was giving false warnings. Our primary focus is safety and performance and when we received these batteries back, there was nothing wrong with the cells but that is how we determined the software was too conservative. I am sure it was an inconvenience to these battery owners, but we would rather be on the side of caution than not.

Thanks Kathy, that was the info I was looking for.
 
Unregistered confession....

So, I put an EarthX ETX 680 in my plane.

Unknown to me, my ammeter had suffered infant mortality (ok, I bought it used!) AND I also had a blown over-voltage module which took my alternator off line. And yes, my plane is purely analogue.

Soooo, I ended up flying over 7 hours on my electrically-dependent engine (as in no battery or alternator and the fan quits) when I finally noticed a suspicious drop on my voltmeter.

I was 20 miles from home over inhospitable territory.

I limped home, got my sh_t together and figured out I had been running on battery power alone for the entire 7 hours on the hobbs - which was also the first 7 hours of phase 1.

I kind of fell in love with my EarthX after this experience. I charged it up and it has been perfect ever since.

Boy, I'm sure glad I posted this as unregistered so no one knows who this idiot is! Oh, wait....????
 
EarthX with a 540

I have used both an ETX900 and an ETX1200 in my RV-10. Both seem to crank the engine the same speed (very fast). The battery was mounted on the firewall far too close to the exhaust which caused a little deformation of the case due to radiant heat. It still performed perfectly but I wanted to change the location. When I contacted EarthX about the case bulge they suggested that I send it in to get checked out (at no cost) so while I was doing that I decided to just upgrade to the ETX1200. It wasn't for the lack of cranking speed, it was for extra capacity since I have a CPI ignition and all glass panel. If I had to do it over again I would just go with the ETX1200.

I've been flying since Nov and already have just under 150 hours (hobbs) on the aircraft.

It's a great product and EarthX provides fantastic customer service.
 
ETX900 in mine

I've been flying with an ETX900 for about a year now with no issues, even prolonged cranking after a botched hot start has been uneventful. The 35# hunk of lead that I replaced with the ETX now resides in a more appropriate machine - my lawnmower...
 
its not does it work.. but when it fails...

I am sorry, the issue with Li batteries is not can they crank, can they sit, can they deliver amps, but when they fail under charging when everything else is working....the stats will tell over time what is safe or not, is the 10 lbs worth the risk of a fire etc...I lost 20 lbs and put the weight in a reliable battery...better for me and taking a red/yellow box out of my risk analysis. To each is own...fly happy and long. I am very happy to recycle lead batteries with high efficiency (LCA) and fly with Odyssey batteries and keep the weight off MY gut....;)
 
Michael,
I'm sorry, but I don't quite understand the question. If you're concerned about an EarthX bursting into flames like other lesser lithiums we've seen in the news, be advised that this Lithium IRON PHOSPHATE battery has a different chemistry than those other batteries, and is not susceptible to such thermal runaway.

I'm not sure what "fail under charging" means. In any case, the battery management circuits well give you an indication of problems long before the battery simply fails.

If you're concerned with an over-voltage from the charging system, this battery internally disconnects incoming charge at 16.0 volts, while still sending outbound battery power to the rest of the system. As we saw in Indwarrior's post above, that power lasts a long time.

Hey, Kathy, in the past year, have any ETXs simply failed?
 
SNIP

If you're concerned with an over-voltage from the charging system, this battery internally disconnects incoming charge at 16.0 volts, while still sending outbound battery power to the rest of the system. SNIP

This is the element that concerns me. Perhaps I don't understand but reading the EarthX manual I see how the battery is protected - but do not see how the panel is protected from the run away alternator that now has no battery as a sump to mitigate the overvoltage condition.

In a typical install if a voltage regulator fails output voltage can go very high. A standard battery will mitigate some of this overvoltage condition as the alternator can only put out so much current. This will not last forever but it might buy the pilot time to figure out what is happening and take the alternator off line before his panel fries. The 1 second delay in the EarthX disconnecting on overvoltage to 'allow the alternator overvoltage crowbar to work' does a nice job at protecting the battery but at the expense of 50+ volts going into the panel if the overvoltage protection does not work.

Nothing replaces alternator overvoltage protection but as we have seen this does happen. Having overvoltage warnings is also a must. The EarthX approach to protect the battery on overvoltage and ignore the rest of the plane would not be how I would design the system.

Carl
 
I copy all that, Carl.
I forget that not everyone is set up like my aircraft...I have a VPX pro managing my electrics, including the charging system. If my voltage regulator fails, my VPX disconnects the alternator field at 15.9 volts, leaving just the battery. If a 16 volt spike makes it through, the battery managers disconnect charging input, but still allow the battery output.

All this came from extensive back-n-forth QnA with the folks from EarthX and Vertical Power at Oshkosh this year. By "back-n-forth", I was trotting back and forth between their booths with new questions until I was satisfied. I, too, want to make sure my electronics are protected from a 'Chernobyl' failure.

Of note, I'm not sure if this answers any of the OP's questions, but both vendors complimented my setup.
 
protection/failure modes...risk management...etc

The safety of one cathode material over the other is debatably, and being done by people much smarter than I...and the safety of the anode, lithium metal build up, etc.....we all fill our cockpits, tail section, and engine compartments with electronic/mechanical "toys" meant to do a job. My point was lithium batteries have certain failure risks, that must be mitigated to insure safety, and in my choice/opinion, solve a problem that does not exist in our RVs, this is based on weight and/or electrons needed to start or get out of IFR to VFR and safely on the ground with a 100% charging system failure. I ran two hours (in good VFR!) with an odyssey 925, landed, and started with good cranking power. If folks want to carry xxx amps with yyy less lbs, more power to ya...enjoy the amps sitting in your battery, fly safe, and do check your voltage often, good for all of us to do...;)
 
Simply, factually, proven, not true.

Michael,
I'm sorry, but I don't quite understand the question. If you're concerned about an EarthX bursting into flames like other lesser lithiums we've seen in the news, be advised that this Lithium IRON PHOSPHATE battery has a different chemistry than those other batteries, and is not susceptible to such thermal runaway.

Sid, Yes the LiFePh is different, and that the thermal event temperature peak is lower than most other Li chemistries, but it does exist. EarthX has clearly put a lot if investment and technology into mitigating the contributing factors to such an event, but lets not get carried away and say it is gone. It is fenced in, but not gone. It must be considered in the installation. If it is located in the cabin, vapor containment and venting is in order as it may get hot enough to smoke the plastic container.

Oversimplified, a thermal event is triggered by a combination of internal energy and temperature. They are not totally immune to the charging voltage and AC content, yet. We have to do our part mitigating the possibility with the installation.

Performance wise - it is a far superior energy storage unit. Still some failure mode refinement to be accepted and executed.
 
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Got it, Bill.
I should have written "not AS susceptible..."

I still really do like the battery.
 
EarthX battery

I, too, am happy so far with my EarthX replacement for my 680 in my RV7. Recommendations for hooking the error code wire to my Skyview? Still need to do that...
 
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