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Old 06-13-2019, 05:49 AM
Luchnia is offline
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Originally Posted by crash-n-burn View Post
You simply cant do that with a LIPO or a A123.
You cannot load test a LIPO or A123 battery? How so? You can load test most any battery. Or are you implying the 8-ball cannot load test the other chemistries?
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Old 06-13-2019, 06:00 AM
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A123 batteries don't load test well since their discharge curve is more of a cliff but lithium polymer/ion cells load check just fine.

As far as what batteries to use, I'm weird. I run RC car lipos. The hard plastic case they come in makes them ridiculously easy to mount/remove and compared to how they'd be abused in a car, they're just loafing along running some BLS157s.
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Old 06-13-2019, 06:26 AM
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I use the 8 Ball for both of my Li-Ion and 2 cell LiPo's.
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Old 06-13-2019, 06:32 AM
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A 123 batteries are very "stiff", in battery terms, so applying a 1amp load to them doesn't drop the voltage much. But the bigger deal as Jack alluded to above, is that unlike Lipo or LiIon or NiMh or NiCd, or even lead acid, the discharge curve is very flat. So you can't tell how much battery is left by measuring the voltage, even under load. A123's stay at a nearly flat voltage until they are very nearly exhausted. Then the voltage drops off a cliff rapidly.

Using A123's means that you recharge after a flight or 2 to see how much you use per flight. I use 300 - 400 mah per flight out of each of 2 packs as an example. That means, for me, 4 flights uses maybe half the battery capacity of a 2500mah.

And over the course of using them, I occasionally check the battery capacity with a full charge/discharge cycle at 1/10 to 1/5 of the rating. So I do a discharge at 250-500 mah over 5-10 hrs to establish a baseline for when the batteries are new and simply keep track. A123's, at least the genuine ones, have an amazingly long life if not over charged or discharged.
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Old 06-13-2019, 06:45 AM
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I use Fromeco Relions (5200's) on all 100cc and up planes. And their Wolverine switch. That's all, nothing more. Well, plus an ignition battery and switch, although my latest I'm going with a SparkSwitch for ignition.

10,400 mAh is plenty of battery for all day flying if you use 300 - 400 mAh per flight.
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Old 06-13-2019, 08:13 AM
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Quote:
Originally Posted by Luchnia View Post
You cannot load test a LIPO or A123 battery? How so? You can load test most any battery. Or are you implying the 8-ball cannot load test the other chemistries?

Yeah I guess I mean I don't know of a load tester that has the ability to load test an A123 or lipo. A 1 or 1.5 amp load on those types of batteries is not going to tell you much.
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Old 06-13-2019, 10:58 PM
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Originally Posted by dhal22 View Post
I use Fromeco Relions (5200's) on all 100cc and up planes. And their Wolverine switch. That's all, nothing more. Well, plus an ignition battery and switch, although my latest I'm going with a SparkSwitch for ignition.

10,400 mAh is plenty of battery for all day flying if you use 300 - 400 mAh per flight.

Are you able to charge them from the jack on the outside of the switch? and what kinda charger do you use?
my two big things are i want to know how much im putting back into the batterys, and i want to be able to charge from the outside of the plane while at the field and not need to take off the canopy. I know you can you can fly all day on your mah. but if you had to.
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Old 06-14-2019, 06:13 AM
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Are you able to charge them from the jack on the outside of the switch? and what kinda charger do you use?
my two big things are i want to know how much im putting back into the batterys, and i want to be able to charge from the outside of the plane while at the field and not need to take off the canopy. I know you can you can fly all day on your mah. but if you had to.
Yes, I charge right thought the Fromeco Wolverine switch. I currently use the Revoletrix Cellpro 6 charger. They are selling the GT500 for $75 (closeout model I think). I bought one of those but haven't used it yet.

Even the Cellpro Multi4 will work fine.
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Old 06-14-2019, 07:57 AM
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I also am charging my Li-Ions through an external port. I am using the Revolectrix 500 duo in the toy hauler and have a Hitec X2 in the shop.
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Old 06-14-2019, 09:47 AM
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Originally Posted by RCAddiction View Post
A 123 batteries are very "stiff", in battery terms, so applying a 1amp load to them doesn't drop the voltage much. But the bigger deal as Jack alluded to above, is that unlike Lipo or LiIon or NiMh or NiCd, or even lead acid, the discharge curve is very flat. So you can't tell how much battery is left by measuring the voltage, even under load. A123's stay at a nearly flat voltage until they are very nearly exhausted. Then the voltage drops off a cliff rapidly.

Using A123's means that you recharge after a flight or 2 to see how much you use per flight. I use 300 - 400 mah per flight out of each of 2 packs as an example. That means, for me, 4 flights uses maybe half the battery capacity of a 2500mah.

And over the course of using them, I occasionally check the battery capacity with a full charge/discharge cycle at 1/10 to 1/5 of the rating. So I do a discharge at 250-500 mah over 5-10 hrs to establish a baseline for when the batteries are new and simply keep track. A123's, at least the genuine ones, have an amazingly long life if not over charged or discharged.
I have used this tester https://m.aliexpress.com/item/328895...il2msiteDetail for many years on A123's. It always matched up to my cellpro charger, flight counting data and when I used an Icharger. It measures each cell to the 3rd decimal. Incline it very accurate and consistent.

FYI, I didn't buy it at this distributor, I just searched for a quick link.
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Old 06-14-2019, 09:55 AM
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Originally Posted by jamesrxx951 View Post
I have used this tester https://m.aliexpress.com/item/328895...il2msiteDetail for many years on A123's. It always matched up to my cellpro charger, flight counting data and when I used an Icharger. It measures each cell to the 3rd decimal. Incline it very accurate and consistent.

FYI, I didn't buy it at this distributor, I just searched for a quick link.
I have the same tester. It only tells the cell voltage. Cell voltage in a battery with a flat discharge curve like an A123 unfortunately does not tell you what's left in the pack. Sure, it reads the same voltage as my DVM or Cellpro or Powerlab 8. But even those excellent chargers don't know how much has been used until it attempts to do a full charge or discharge.

These voltage meters are more useful for Lipo and LiIon because they drop voltage significantly during use, but not for A123.
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Old 06-14-2019, 11:47 AM
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Originally Posted by RCAddiction View Post
I have the same tester. It only tells the cell voltage. Cell voltage in a battery with a flat discharge curve like an A123 unfortunately does not tell you what's left in the pack. Sure, it reads the same voltage as my DVM or Cellpro or Powerlab 8. But even those excellent chargers don't know how much has been used until it attempts to do a full charge or discharge.

These voltage meters are more useful for Lipo and LiIon because they drop voltage significantly during use, but not for A123.
But it does give you a percentage of charge. And that percentage matches up with my cellpro charger very accurately. So you can use that voltage meter to let you know what percentage is left.
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Old 06-14-2019, 12:34 PM
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Sorry, but I own (5) Cellpro/PowerLab chargers. Even the excellent Cellpro's % of charge is wrong in terms of capacity on A123's. It's measuring voltage, not capacity. Voltage and capacity unfortunately don't correlate on a battery with a flat discharge curve such as an A123. Not sure how better to explain this, but I will try to give you an example.

Freshly charge the battery to 100% and take it off the charger. Then come back a week later and reconnect the battery. The Cellpro will initially provide an estimate of something like 85-95%. You dutifully try to charge it and find that it added only a few mah and shuts off. The battery was still essentially at 100%, not 85 or 90. (90% would be 250 mah drained out).

There's a big dip at the beginning of the curve and an even bigger falloff at the end of the curve.

The danger for flying and relying on voltage measurement with an A123 does not lay in when the battery is nearly full. It's that the voltage curve is super flat. Take a look at a discharge curve. An A123 will give you a nice voltage right up until the point when it's about to dive off the cliff. You will use that meter and think you are fine since the voltage hasn't really dropped. But it can be almost "empty" at essentially the same voltage. That's inherent in the chemistry. Generic LiFe pouch packs have a little bit of a curve, but not much.
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Old 06-14-2019, 02:29 PM
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Originally Posted by RCAddiction View Post
Sorry, but I own (5) Cellpro/PowerLab chargers. Even the excellent Cellpro's % of charge is wrong in terms of capacity on A123's. It's measuring voltage, not capacity. Voltage and capacity unfortunately don't correlate on a battery with a flat discharge curve such as an A123. Not sure how better to explain this, but I will try to give you an example.

Freshly charge the battery to 100% and take it off the charger. Then come back a week later and reconnect the battery. The Cellpro will initially provide an estimate of something like 85-95%. You dutifully try to charge it and find that it added only a few mah and shuts off. The battery was still essentially at 100%, not 85 or 90. (90% would be 250 mah drained out).

There's a big dip at the beginning of the curve and an even bigger falloff at the end of the curve.

The danger for flying and relying on voltage measurement with an A123 does not lay in when the battery is nearly full. It's that the voltage curve is super flat. Take a look at a discharge curve. An A123 will give you a nice voltage right up until the point when it's about to dive off the cliff. You will use that meter and think you are fine since the voltage hasn't really dropped. But it can be almost "empty" at essentially the same voltage. That's inherent in the chemistry. Generic LiFe pouch packs have a little bit of a curve, but not much.
I own power lab 6, 10S, and 2 4 channel charger. And they all agree with each other and the the cell checker I have. To the point where the margin of error is very little. Yes it does not measure capacity. No test does unless you do a full cycle in which I do a few times a year. However the software is good enough to determine what percentage of the capacity is by a percentage bases going off each cell voltage. I have been using genuine FROMECO A123's before I remember seeing LIFE batteries. And the original thought was you could not check an A123 but these cell checkers and cellpro chargers seem to be really accurate.
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Old 06-14-2019, 02:34 PM
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Yes, I charge right thought the Fromeco Wolverine switch. I currently use the Revoletrix Cellpro 6 charger. They are selling the GT500 for $75 (closeout model I think). I bought one of those but haven't used it yet.

Even the Cellpro Multi4 will work fine.
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I also am charging my Li-Ions through an external port. I am using the Revolectrix 500 duo in the toy hauler and have a Hitec X2 in the shop.
Thank you both, i guess that is one nice feature of the Wolverine switch.

my buddy is worried about having to make a big hole in plane for it to mount in the fuse. the plane used to have two reg type rx switches but one has been removed. they were one behind the other.
i use power lab 6 and have the GT1200, i have a cell pro 4 right now guy was suppose to buy it but hasn't yet.
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