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EarthX Trickle Charger

4nneK

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I just replaced the old lead-acid battery in my legacy 12 with an EarthX. In the past, I would occasionally connect a trickle charger to make sure the battery was topped off. Especially when playing with the avionics on the ground.

I know the new lithium battery isn't compatible with the cheap old trickle charger that I was using, so I'm looking for a replacement. What are you all using to keep your lithium batteries charged?

It looks like EarthX sells a trickle charger, but it is a little more expensive than my uninformed brain expected.

Also, is it normal to see amps bouncing between 0 and 1 during the flight duration? I truly can't remember if the plane has always had these low amps (still in the green arc though.)
 
I just replaced the old lead-acid battery in my legacy 12 with an EarthX. In the past, I would occasionally connect a trickle charger to make sure the battery was topped off. Especially when playing with the avionics on the ground.

I know the new lithium battery isn't compatible with the cheap old trickle charger that I was using, so I'm looking for a replacement. What are you all using to keep your lithium batteries charged?

It looks like EarthX sells a trickle charger, but it is a little more expensive than my uninformed brain expected.

Also, is it normal to see amps bouncing between 0 and 1 during the flight duration? I truly can't remember if the plane has always had these low amps (still in the green arc though.)
Hi Anne, I also just put an EarthX battery in my -12. I bought the ‘special’ charger and the instruction say to attach the charging cables to the battery BEFORE plugging the unit into the wall! Apparently ,it measure battery condition first, then charges accordingly.
Cheers….😀
 
I am operating my EAB with an EarthX battery.

You might be posting here about this due to the special requirements that the EarthX has for its charging. It is right to use caution when making this choice. The charging of a LI-ON battery shouldget extra attention. I use the charger EarthX sells. As a general rule I dont leave mine plugged in for long periods of time. I did not research other charging options.
 
What Brian said. Absolutely get the charger that EarthX recommends. Yeah, it's kinda expensive, but so is the battery--and you don't want to risk damaging it. I've had my EarthX battery installed for three years and it's still going strong.
 
I am operating my EAB with an EarthX battery.

You might be posting here about this due to the special requirements that the EarthX has for its charging. It is right to use caution when making this choice. The charging of a LI-ON battery shouldget extra attention. I use the charger EarthX sells. As a general rule I dont leave mine plugged in for long periods of time. I did not research other charging options.
Just a clarification - the EarthX is a LiFePo4 battery.
 
Anne,
You want the EarthX charger/minder for a few reasons beyond what was mentioned above.

First, yes, it is the proper ground charger for that LiFePo4 battery.

Next, the charger establishes a digital "handshake" with the BMS to rebalance the voltages in each cell. Per their recommendations, I balance the cells every couple of months (especially in the winter) as a point of basic battery maintenance. Mine is over 5 years old and still going strong.

Finally, if you do discharge the battery to that 95% point where the BMS internally disconnects the battery, the EarthX charger engages with the BMS to "reopen" the battery and allow a total recharge. Battery saved.

Now, regarding your amps reading: Depending on how your alternator/ammeter is set up, yes, reading 0 to 1 amp is probably fine. Once the alternator has recharged the battery after the huge load of an engine start, your alternator is providing what current the airplane's systems needs to operate. 0 to 1 amp shows the alternator is meeting the airplane's electrical need, with a little extra available for the battery (and the battery's not using it...no need). Bear in mind, though, that the post-engine-start recharge demand will be high: The EarthX opens its mouth wide after engine start, taking in is much recharging current the alternator can provide. Then, after a few dozen seconds, the recharge current drops down steadily. This alarmed me at first, but Kathy at EarthX described how this recharge schedule is normal for the EarthX.

I love this battery.
 
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As a general rule, I never run avionics on a battery charger, I use a 30 amp regulated power supply. While some chargers are clean, many have trash on the output. My ~$100 power supply acts just like an alternator for powering ship loads and to charge the batteries if they need it.

Also on this point pMag specifically forbids having a charger connected when power is applied to the pMags (they don’t know what kind of charger you are using so they assume the worst). If you have pMags and want to connect a charger, first open the pMag breakers.

Carl
 
As a general rule, I never run avionics on a battery charger, I use a 30 amp regulated power supply. While some chargers are clean, many have trash on the output. My ~$100 power supply acts just like an alternator for powering ship loads and to charge the batteries if they need it.

Also on this point pMag specifically forbids having a charger connected when power is applied to the pMags (they don’t know what kind of charger you are using so they assume the worst). If you have pMags and want to connect a charger, first open the pMag breakers.

Carl

The EarthX recommended chargers have a power supply mode to allow them to do double duty.
 
SNIP:
Next, the charger establishes a digital "handshake" with the BMS to rebalance the voltages in each cell. Per their recommendations, I balance the cells every couple of months (especially in the winter) as a point of basic battery maintenance. Mine is over 5 years old and still going strong.
SNIP:
Interesting! Do you have any documentation on this feature? I can't seem to find any reference to it on the EarthX charger webpage.
 
As a general rule, I never run avionics on a battery charger, I use a 30 amp regulated power supply. While some chargers are clean, many have trash on the output. My ~$100 power supply acts just like an alternator for powering ship loads and to charge the batteries if they need it.

Also on this point pMag specifically forbids having a charger connected when power is applied to the pMags (they don’t know what kind of charger you are using so they assume the worst). If you have pMags and want to connect a charger, first open the pMag breakers.

Carl
...speaking of "Trash on the output" -- Go for a flight with a descent O-scope and look at the alternator output -- amazing and frightening the amount (amplitude, frequency, duration) of noise there is...more to come on a different thread...
 
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Finally, if you do discharge the battery to that 95% point where the BMS internally disconnects the battery, the EarthX charger engages with the BMS to "reopen" the battery and allow a total recharge. Battery saved.

I love this battery.
All true and I love mine also. (Have been using Earth-X for almost 10 years and same chemistry for ~20 years in other applications, zero issues)

The BMS will "open" when the battery is pretty much completely discharged BUT the battery will continue to discharge more and does not take long till the battery cannot be recovered. That time period could be as short as 2 weeks from what others have seen at my field. Others here might have seen longer periods of time.

For me any true low amp charger that is made by Optimate for LiFePo4 has worked well. Even their solar charger at 0.8 amps works well but also there 0.8, ~5 and ~10 amp also works fine unless you are looking to charge your battery very quickly then a 10 amp is needed. My main "trickle" charger is my Optimate TM-471's ($64.49)

 
Interesting! Do you have any documentation on this feature? I can't seem to find any reference to it on the EarthX charger webpage.
I'm basing my comments on the EarthX Lithium Battery Users Manual pages 43 and 44, the Option2 paragraph:

"IF YOUR BATTERY IS AT ZERO VOLTS:
Option2: If the battery was manufactured before 2017, or the voltage at the terminals is still near zero volts even with the battery cables removed or load removed, then you will need to use a lithium Optimate brand charger with a BMS Reset feature. If you do not have an Optimate charger, go to Option 3 below. Connect an Optimate charger to the battery first, then plug the charger into AC power (Optimate model TM-291), the “Save” LED on the charger should illunate indicating the battery is charging. Other lithium Optimate chargers (model TM-275 or TM-281) have a “Reset” button, if so, press and hold the “Reset” button until the “Save” LED on the charger is illuminated also indicating the battery is charging. If the Optimate does not indicate it is charging, then contact EarthX Tech Support."

Now, I must now admit that my knowledge has become dated given that the post 2017 models are improved regarding the BMS' ability to reconnect more easily (hence, the Option 1 paragraph). EarthX has clearly improved their product lines.
 
I'm basing my comments on the EarthX Lithium Battery Users Manual pages 43 and 44, the Option2 paragraph:

"IF YOUR BATTERY IS AT ZERO VOLTS:
Option2: If the battery was manufactured before 2017, or the voltage at the terminals is still near zero volts even with the battery cables removed or load removed, then you will need to use a lithium Optimate brand charger with a BMS Reset feature. If you do not have an Optimate charger, go to Option 3 below. Connect an Optimate charger to the battery first, then plug the charger into AC power (Optimate model TM-291), the “Save” LED on the charger should illunate indicating the battery is charging. Other lithium Optimate chargers (model TM-275 or TM-281) have a “Reset” button, if so, press and hold the “Reset” button until the “Save” LED on the charger is illuminated also indicating the battery is charging. If the Optimate does not indicate it is charging, then contact EarthX Tech Support."

Now, I must now admit that my knowledge has become dated given that the post 2017 models are improved regarding the BMS' ability to reconnect more easily (hence, the Option 1 paragraph). EarthX has clearly improved their product lines.
The BMS reset functionality of the Optimate is well documented, I was referring more to the cell balancing that you mentioned. Would like to know more about that.
 
The BMS reset functionality of the Optimate is well documented, I was referring more to the cell balancing that you mentioned. Would like to know more about that.
If this what you are asking about? The BMS can charge a battery cell by cell to insure one cell is not overcharged leaving other cells undercharged. Both will damage the longevity of a LiFePo4 battery.

From Earth X:

All types of lithium batteries (not just ours) require a “BMS” that monitors and balances the cell charge and protect from over discharge or over charge.
 
The BMS reset functionality of the Optimate is well documented, I was referring more to the cell balancing that you mentioned. Would like to know more about that.
From the same manual's chart on LED light actions:

From page 6:
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From page 2:
1751993728457.png

From page 5:
1751993906806.png
 
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I just replaced the old lead-acid battery in my legacy 12 with an EarthX. In the past, I would occasionally connect a trickle charger to make sure the battery was topped off. Especially when playing with the avionics on the ground.

I know the new lithium battery isn't compatible with the cheap old trickle charger that I was using, so I'm looking for a replacement. What are you all using to keep your lithium batteries charged?

It looks like EarthX sells a trickle charger, but it is a little more expensive than my uninformed brain expected.

Also, is it normal to see amps bouncing between 0 and 1 during the flight duration? I truly can't remember if the plane has always had these low amps (still in the green arc though.)
In the grand scheme of things, the price of the charger is a small price to pay for the health and well-being of your battery, avionics, and plane.

Sometimes, the best(?)/right(?) stuff just costs a bit more.

You will be glad that you did it.

Note that they have different sizes. You may want to have a chat with Kathy and determine which one best suits your needs.
 
Between flight battery charging is a thing of the past with the EarthX battery unless;
1. You have a parasitic drain.
2. You only fly once every 6 months.
3. Your voltage regulator is not set for the right voltage, 14.2V optimum.
5. You have left the plane on for extended periods working on avionics or ??
 
Between flight battery charging is a thing of the past with the EarthX battery unless;
1. You have a parasitic drain.
2. You only fly once every 6 months.
3. Your voltage regulator is not set for the right voltage, 14.2V optimum.
5. You have left the plane on for extended periods working on avionics or ??
Makes sense. I never charge between except for the before-mentioned cell balance charges.
 
The optimate 275 v2 (for 12v systems) is on sale on amazon prime... fyi
 
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The optimate 275 v2 (for 12v systems) is on sale on amazon prime... fyi
I just looked and it is available on Prime, it's just not a deal for Amazon Prime Day discounts. Probably would have bought one if it was, but I'll wait until I really need it.
 
I just sold my RV7 and my hangar. Now I have an Optimate TM291 charger that I don't need and will sell for $70. I'll pay the shipping.
 

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I have a small NOCO Genius charger that can be switched between AGM and Lithium modes. EarthX gave me the green light to use this charger (in Lithium mode of course).
 
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