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Earth-X Geriatrics

wawrzynskivp

Well Known Member
I have an ETX 680 that is about five years old and been in service for 3 1/2 years. It hadn't shown me any real degradation, until it got really cold.

Cold cranking Amps should be 320 at 0F but at perhaps 8F I got about three turns and went into solenoid stuttering. With a few attempts with lots of recovery time in between it did start, but it was very close to failing.

Once it warmed up it behaved very normally. Normal amount of charging for voltage state etc.

So for you Earth-X folks beware the cold cranking capability as it ages.
 
Charger-tender

Duck,
By chance have you connected the battery to EarthX’s charger? It’ll rebalance the cells, which improves the battery’s performance and longevity.
 
Earth-X Charger

Hey Scroll,

Best I can say is: 'I think so?'

I got the LiFe charger, can't recall if it was from Earth-X themselves. I'll look into it, thanks for the hint.

Update: No I didn't use their charger, now on order.
 
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Kind of, not really.

The cell "balancing" is a function of the BMS in the battery pack, not in the external charger. (The cells are all connected in series, so to the outside world they appear as one cell, not individually addressable/chargeable nodes.)

There is a life limit for LiFePo cells, I can't quote you days/months/years or cycles at the moment. I seem to recall reading in the EarthX literature that 5 years was the useable life of one of their packs...

But, definitely want to use a charger designed for LiFePo cells vs Flooded Cells, AGM types...

Cheers!

B
 
The cell "balancing" is a function of the BMS in the battery pack, not in the external charger. (The cells are all connected in series, so to the outside world they appear as one cell, not individually addressable/chargeable nodes.)

There is a life limit for LiFePo cells, I can't quote you days/months/years or cycles at the moment. I seem to recall reading in the EarthX literature that 5 years was the useable life of one of their packs...

But, definitely want to use a charger designed for LiFePo cells vs Flooded Cells, AGM types...

Cheers!

B

Yep. From Earth-X's website:

Other companies sell a balancing charger, which you have to plugin periodically to “top off” and balance the cells. Inside every one of the ETX-Series batteries is a microprocessor Battery Management System (BMS) that monitors the charge level of each cell and balances the charge when needed, protecting the cells from overcharge or over-discharge.​

Skylor
 
I

Cold cranking Amps should be 320 at 0F but at perhaps 8F I got about three turns and went into solenoid stuttering.

Vince,
Did you put a load on the cold battery prior to trying to crank? I have a Lifepo4 in another plane and they recommend that specifically for <32F.

Warming the LiFePO4 Battery Before Starting Your Vehicle
Once temperatures start to reach the mid-40s it is often helpful to warm the battery before starting. This doesn’t mean you need to wrap your battery in an electric blanket, or take a blow dryer out to heat up the battery! Instead we suggest running your headlights, running lights, or an accessory such as the radio for 30 seconds prior to starting your ATV.
 
Warming the LiFePO4 Battery Before Starting Your Vehicle
Once temperatures start to reach the mid-40s it is often helpful to warm the battery before starting. This doesn’t mean you need to wrap your battery in an electric blanket, or take a blow dryer out to heat up the battery! Instead we suggest running your headlights, running lights, or an accessory such as the radio for 30 seconds prior to starting your ATV.
[/QUOTE]


Hey Bob,

Thanks, I didn't know that.

To answer your question: Not in the sense described in the reference. I did have a few failed starts, then a successful start. Perhaps the warm-up is why it eventually gave it a good crank.

But to the aging effect: This is my third winter in these low temps and the first time I saw a failed start.
 
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Flipping on the battery master and letting the EFIS go through its boot, AHRS alignment, song-and-dance should be enough amps and time to warm up the battery before turning the key or hitting the start button.
 
+1

Flipping on the battery master and letting the EFIS go through its boot, AHRS alignment, song-and-dance should be enough amps and time to warm up the battery before turning the key or hitting the start button.

This type of chemistry takes some getting used to. For the first 3 years it's pretty much the same as lead acid. (Providing you don't leave the master on overnight) After that ensure the cells stay balanced and give it a minute to warm the electrons in the winter.
 
Best way to warm up your EarthX prior to start would be a good load like pitot heat or landing iights. An electric gyro spinning up would help. As we transition to more glass panels and LED lighting it might come down to pitot heat for any real load on the battery.
 
From Earth-X's website:
Other companies sell a balancing charger, which you have to plugin periodically to “top off” and balance the cells. Inside every one of the ETX-Series batteries is a microprocessor Battery Management System (BMS) that monitors the charge level of each cell and balances the charge when needed, protecting the cells from overcharge or over-discharge.​


Seriously, is there any automotive or aircraft LiFePO battery without internal cell management?
 
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Seriously, is there any automotive or aircraft LiFePO battery without internal cell management?

I dont know anymore, but the first couple that ACS sold (well before EarthX existed) had pretty much NO internal BMS. The well-circulated video of a “smoke event” in a homebuilt was one of those, and it haunts the LiFePO battery world to this day - sort of like claiming that all modern cars are as hard to start as a Model A….. things advance!
 
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Seriously, is there any automotive or aircraft LiFePO battery without internal cell management?

Shorai. Working fine for Dave Anders, me and a few others here on VAF years later.
 
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I'm speaking of cell balancing, the subject of the referenced EarthX note, not over-voltage protection, the issue resulting in battery melt and smoke.

Are there any LiFePO batteries without active (chip based) or passive (resistor based) cell balancing? Best I know, it's required for any practical LiFePO pack.
 
+1

Dan it has external cell balancing not an internal BMS, it makes the battery much less expensive.

But requires you to connect the external charger periodically to balance the cells. My preference (personal) is to have the BMS in the battery take care of the balancing in flight, and I never have to mess with a ground charger.
 
I have an ETX 680 that is about five years old and been in service for 3 1/2 years. It hadn't shown me any real degradation, until it got really cold.

Cold cranking Amps should be 320 at 0F but at perhaps 8F I got about three turns and went into solenoid stuttering. With a few attempts with lots of recovery time in between it did start, but it was very close to failing.

Once it warmed up it behaved very normally. Normal amount of charging for voltage state etc.

So for you Earth-X folks beware the cold cranking capability as it ages.

I just bought my second Earth-X ETX900 and wanted to do a report card on the one I replaced, so this was a timely thread to do it.

I originally purchased the first one 4 and 1/2 years ago (June of 2018) Mine is mounted on the firewall, and I had some issues at first because I had not protected the battery properly from the heat from the convection from the exhaust after shutdown and the hot environment during flight. I knew this, because i wired the fault indicator to one of the discrete inputs to the G3X touch. The BMS told me of the high temp. It got so hot once that the battery case deformed on the bottom. Earth-X (to their credit), re-cased my battery for free and I reinstalled with a full enclosure, and top shroud that bathed the battery with cooling air from the plenum via a 3/4 inch scat hose. No problems since.

Recently When the engine was cold (thick oil), and with my 10 to 1 pistons, the battery would trip on high current sensing, and the BMS would shut off for a few minutes. After a few tries, when it would get over the first hump of compression, it would start normally. The battery was just getting old, I guess.

After consulting with Earth-X, I bought a brand new 900, which has newer software running the BMS, and Wow what a difference a fresh one makes. The voltage will not even drop now enough to kick the G3X screen off line, while cranking.

The new one spin's the 10 to 1 pistons over like crazy, even when cold.

The old battery still would be great for a mower, 4 wheeler, etc. It has over 350 hours flight time, probably 600 plus start cycles on it, and who knows how many turn ons, for loading software in the screens, etc.

This is great product, but they all have a service life, so maybe it's time to upgrade to a newer one.
 
Dan it has external cell balancing not an internal BMS, it makes the battery much less expensive.

The "how" is probably simple charge limiting. I have a note out to Shorai.
 
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Battery cases

Just FYI the EarthX 680, 900 and 1200 have the exact same case size if you want to add a little more ampacity next time you swap it out. My 900's are 4 years old to date (2.5 years flying) and to date little to no degradation in ampacity and I also did not take care of heat issues early on. Now have blast tubes and Anti-splat exhaust shield in place and lower battery is 40 F cooler.
 
The "how" is probably simple charge limiting. I have a note out to Shorai.

I'd be interested in knowing how this works - I had thought that a BMS was mandatory to be able to address the exact voltage of each individual cell.
 
One more data point

My first Earth-X lasted just under 5 years and the warning light started to flash in flight. I did not notice any reduced performance but got a new one shortly after.

Cheers, Sean
 
More care/feeding...of the alternator...

Pay particular attention to the size/type of the EarthX battery installed AND the rated output (in AMPS) of your alternator/regulator.

LiFePo batteries have an extremely small amount of internal resistance, so it is possible to exceed the design limits of the alternator when charging the battery (right after start is usually the worse case).

When I used an ETX 900 (because I wanted the additional Ah of runtime), I would regularly see 80+ amps across the shunt from the Alternator (Plane Power AL12-EI60). This was a short duration while the battery charged, but it was not good practice for the health/longevity of the alternator.

I suppose this is why EarthX tries to guide you to a particular battery based upon engine size -- I would prefer that they just came out and said what the limiting parameter was (AMPS, etc.).

I am now running an ETX 680 and will see 50 AMPs when the battery is drained after starting. Well within limits.
 
Pay particular attention to the size/type of the EarthX battery installed AND the rated output (in AMPS) of your alternator/regulator.

LiFePo batteries have an extremely small amount of internal resistance, so it is possible to exceed the design limits of the alternator when charging the battery (right after start is usually the worse case).

When I used an ETX 900 (because I wanted the additional Ah of runtime), I would regularly see 80+ amps across the shunt from the Alternator (Plane Power AL12-EI60). This was a short duration while the battery charged, but it was not good practice for the health/longevity of the alternator.

I suppose this is why EarthX tries to guide you to a particular battery based upon engine size -- I would prefer that they just came out and said what the limiting parameter was (AMPS, etc.).

I am now running an ETX 680 and will see 50 AMPs when the battery is drained after starting. Well within limits.

I am curious as to why you are seeing 80 amps…from a 60 amp alternator. The ETX900 can accept a maximum of 80 amps to charge; in this case, it will not draw more than the alternator can supply.

I have two ETX900s in my -10 and have never seen more than 50 amps draw after start, even when the oat is in the low 30s. It also only lasts for a short time. I have a 60 amp alternator, as well.
 
I am curious as to why you are seeing 80 amps…from a 60 amp alternator. The ETX900 can accept a maximum of 80 amps to charge; in this case, it will not draw more than the alternator can supply.

I have two ETX900s in my -10 and have never seen more than 50 amps draw after start, even when the oat is in the low 30s. It also only lasts for a short time. I have a 60 amp alternator, as well.

Bob,

That's interesting -- state of charge will determine how many amps and for how long; maybe you're in a better place than mine were.

Per Tim @ Hartzell, this is "normal" -- their alternators are capable of producing more than the Marketing name implies.

If you can find the test report on your alternator, you can see this documented.

The other concern I had was exceeding the rating of the ANL -- if it opens, that creates a load dump which will fry the diode pack/regulator in short order. Fortunately, ANLs are not fast-acting.
 
My note to Shorai and the response:
____________________________________________

I note a competitor claiming their LiFePO battery incorporates internal cell balancing, and others do not. I am speaking of charging balance, not an over-voltage function as seen in some battery management systems. Does a Shorai LFX have active (chip based) or passive (resistor based) charge balance for each cell?
____________________________________________

Older batteries have a passive based. Newer batteries ~ 2years old have a chip based

cid:9AC09BA4-3550-42AA-A22A-873393B6D7C8

Customer Service | Shorai, Inc. | T:408-720-8821 | [email protected] | www.shoraipower.com
 
Bob,

That's interesting -- state of charge will determine how many amps and for how long; maybe you're in a better place than mine were.

Per Tim @ Hartzell, this is "normal" -- their alternators are capable of producing more than the Marketing name implies.

If you can find the test report on your alternator, you can see this documented.

The other concern I had was exceeding the rating of the ANL -- if it opens, that creates a load dump which will fry the diode pack/regulator in short order. Fortunately, ANLs are not fast-acting.

I have a B&C 60 amp alternator. The performance specs show 59.1 amps at 10,000 rpm (alternator). You will probably find that it takes substantially more current to to open that ANL than is advertised...

Time will tell on the batteries; currently 2 1/2 years old...
 
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