Charging 18650 yields hot cells

Wurkkos

Mr. Nobody

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I have a D2 and a D4 Nitecore chargers.
I just pulled 6 Sanyo cells from a laptop battery and stuck em all on the chargers.
Every battery but two that are slowly charging are EXTREMELY hot!
What is going on here? there slowly making there charge but unsafe due to them being un-holdable.
 

WarRaven

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Stop everything.
Need more info but it sounds bad.

Was voltage checked during pull, as in pairs and then by single Cell? Paired cells can show dead where one is good but held down by a bad cell. Which is which?

The experts will have more info, but I'd stop, remove cells, move them outside for now if you haven't already.
 

bdogps

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Batteries should not get hot when you charge them. None of my 18650 get hot when I charge them. Do you have a multimeter to check their voltage?
 

Mr. Nobody

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the range from 3.78v through 4.01v. they were all on the charger all at once for 2 hours before I checked on them and noticed they were super hot to the touch.
 

Mr. Nobody

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b669dcba0ae95aff405ba60d6dc67ce0.jpg
 

Mr. Nobody

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UPDATE~

There Sanyo UR18650A
Is there a way to measure internal resistance to see which ones are truely bad and which ones are useable ?
 

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