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Charging ST16 battery on external lipo charger

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As others have pointed out the battery in the ST16 is a 1S 8700mAh with a EC2 plug. I ran a discharge curve on it (see below) and didn't expect to see what I did. I initially set the discharge cutoff to 3.2V, then reduced it to 3.1V and then had to reduce it again to 3.0V because I was not seeing the knee. Even at 3.0, the knee was just starting. Could have set it lower, but decided not to push the battery. Most Lipo's are into the knee at 3.2V and heading due south at 3.0V. This battery seems to hold up really well. I got an IR of 38mOhms.
 

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As others have pointed out the battery in the ST16 is a 1S 8700mAh with a EC2 plug. I ran a discharge curve on it (see below) and didn't expect to see what I did. I initially set the discharge cutoff to 3.2V, then reduced it to 3.1V and then had to reduce it again to 3.0V because I was not seeing the knee. Even at 3.0, the knee was just starting. Could have set it lower, but decided not to push the battery. Most Lipo's are into the knee at 3.2V and heading due south at 3.0V. This battery seems to hold up really well. I got an IR of 38mOhms.
What's up with the 0.3v 'spikes' on the discharge curve? Is that normal?
 
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Yes for my charger's discharge process. It periodically spikes to test the LiPo's cell(s). If I run a curve on my Western Mountain analyzer, no spikes. It's nothing to do with the battery.
 
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Li-ion is different than a Lipo.
 
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As others have pointed out the battery in the ST16 is a 1S 8700mAh with a EC2 plug. I ran a discharge curve on it (see below) and didn't expect to see what I did. I initially set the discharge cutoff to 3.2V, then reduced it to 3.1V and then had to reduce it again to 3.0V because I was not seeing the knee. Even at 3.0, the knee was just starting. Could have set it lower, but decided not to push the battery. Most Lipo's are into the knee at 3.2V and heading due south at 3.0V. This battery seems to hold up really well. I got an IR of 38mOhms.
@K3CFPV Does the red line in this graph represent battery capacity? If it does, and I'm reading it correctly, then the battery capacity is about 7400mAh, right?
The IR on mine is 43mΩ.
 
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Ok I have only flown 3 or 4 times and I made the mistake of leaving the TX on for probably over a week. Dont the **** thing have a alarm like my Taranis?

Anyway I tore into the pack and found that it has a small board with chips on it. So I guess that is reason for the weird readings and possibly why connecting it to my Hitec X4 was strange.
 

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Ok I have only flown 3 or 4 times and I made the mistake of leaving the TX on for probably over a week. Dont the **** thing have a alarm like my Taranis?

Anyway I tore into the pack and found that it has a small board with chips on it. So I guess that is reason for the weird readings and possibly why connecting it to my Hitec X4 was strange.
Yeah its a protection circuit which is required by law. In the US its under 49 CFR 173.185 - Lithium cells and batteries.
 

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Yes 0,1 volt different each cel. No worries.
And a different peak voltage charge rate. For max capacity they charge at 0.7C. They can be charged at a higher rate but capacity for a higher charge rate is reduced. That chip set contains a charge limiting feature.

Li-on's have more differences than just the cell voltage.


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