Having trouble Charging Sanyo NCR18650GA

jkid1911

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Trying to charge these brand new just received Sanyo 3500mah NCR18650GA batteries with my Nitecore I2 and I4 chargers. I was advised that they were shipped uncharged and had to be charged before use. I also tried charging the batteries one at a time in each of the chargers as well for a number of hours but they don't get past the first charging indicator light. The second of the three lights flashes but that's as far as they go. Am I missing something? Are the chargers not compatible or am i not waiting long enough for the second light to stay on? I stopped charging them and posted here because I noticed the chargers were heating up as well. For the record each of these chargers have worked flawlessly up to now with all my other batteries. Any help would be appreciated thanks!!
 
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It looks like your I4 has a maximum charging rate of 500Ma per cell and the I2 similar.
To charge a 3500mah cell from empty it will take 7 hours.
If you bought the cells from a reputable source (assuming they are genuine) they are unlikely to have shipped them empty, but even at half full they would need four hours or so to fully charge. Did you leave them that long? Do you have a means of checking their voltage?
P
 
It looks like your I4 has a maximum charging rate of 500Ma per cell and the I2 similar.
To charge a 3500mah cell from empty it will take 7 hours.
If you bought the cells from a reputable source (assuming they are genuine) they are unlikely to have shipped them empty, but even at half full they would need four hours or so to fully charge. Did you leave them that long? Do you have a means of checking their voltage?
P
Hey thanks for the input. i bought them from "18650BATTERYSTORE" and was counting on their authenticity guarantee but they stated their cells are shipped uncharged. I didn't think to ask why.

i have a small voltmeter I could likely try. I'm guessing placing id be placing a prong/probe on each end of the battery? What should it be showing on the meter? Sorry for being a simpleton, I love log hrs but regretfully I'm a bit of a simpleton.

Thanks again for your help and Amy additional input from anyone that could pitch in!
 
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I nicked this from another thread...
Resting voltages:
4.2 volts 100%
4.1 about 90%
4.0 about 80%
3.9 about 60%
3.8 about 40%
3.7 about 20%
3.6 empty for practical purposes

<3.5 = over-discharged

Thanks to DM51, who is a Super Moderator. You don't mess with them if you know what you're doing!


Set the voltmeter to read DC Voltage Red probe to the +ve end and black probe to the -ve.

P
 
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4.2v is full, 3.8v is about half and 3 would be empty. It's a bit nebulous, but I think that's about it. Someone correct me if I'm wrong, please.
Set the voltmeter to read DC Voltage Red probe to the +ve end and black probe to the -ve.
thanks! I'm getting 3.92v is it possible the charger is just not reflecting the charged state accurately or is it that it won't show the progression until I exceed 4.0v of charge?
 
I nicked this from another thread...
Resting voltages:
4.2 volts 100%
4.1 about 90%
4.0 about 80%
3.9 about 60%
3.8 about 40%
3.7 about 20%
3.6 empty for practical purposes

<3.5 = over-discharged

Thanks to DM51, who is a Super Moderator. You don't mess with them if you know what you're doing!


Set the voltmeter to read DC Voltage Red probe to the +ve end and black probe to the -ve.

P
Thanks, wow this is great help! The folks on this forum are awesome!!

I'm guessing maybe I'm just being impatient so I'll give them more time and check them again, thanks again!
 
They usually ship at about 3.4v or 3.5v. For the GA battery, I measured the remaining capacity at about 25% at that level. So, it's getting close to empty. At 500mA charge, you'd think it would take about 5 hours to recharge, but it will actually take a bit longer than that because the last part of the charge gradually lowers the charging current. So, it might take 6 or 7 hours.

Yes, you're being impatient. Or, you might want to get a more recent charger that will charge faster. 1 amp is usually on the low-end for charging 18650's nowadays. 500mA that you're using is really slow.
 
Yep, having a voltmeter is fairly critical to be able to monitor and troubleshoot battery / charger issues, particularly for lithium-ion chemistry
 
Yep, having a voltmeter is fairly critical to be able to monitor and troubleshoot battery / charger issues, particularly for lithium-ion chemistry
For sure and I learned a lot today thanks!

So it turns out that all of the above are correct with their advise too! They took a while but they're showing 4.2v after charging.

So, moving forward....

1, I'll be testing volt output readings before and after charges.
2, I've learned to be patient (and to do the math I learned today) before assuming the worst.
3, buy a newer updated charger for these newer big bruiser batteries.

Thanks to all for your time and kind assistance!!
 
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