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26650 Current

Hemlock_Mike

Hemlock_Mike

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How much current (MAX) will a 4000 mAh
and a 6300 mAh 26650 cell be able to output?
HMike
 





Typically you're safe up to 2C.

Be careful with those ratings though, 6300mAh seems fishy. I would not try to draw more than 6A from those cells without knowing more information about them.
 
I heard the protective pcb will kick in on 7 ampere. Anything lower should be okay. Make sure you monitor the temperature because the battery will heat up.
If the battery don't have protection then make sure the current draw isn't much higher than that.
 
These are the cells for my Starwarz gun. They used to
provide the amps. I likely damaged the protective circuit.
I may have to remove them. I only run it for short times
to protect the cells. I need ~10 AMPS!!!
HMike
 
Last edited:
Maybe look into using an RC lipo pack? :p

The 3100mAh 18650 cells can handle a 6A draw each, could parallel a couple of them.
 
This CO2 laser draws about 10 Amps at 32 volts!!!
That's 8 cells in series.
HM
At first, these cells powered it well but now,
they seem to current limit. I may have damaged the
protection circuits on the cells.
 
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Remove one protection PCb and test the cell but if the current is too high for the protection circuit I wouldn't use the cells in this appliction it's too dangerous
with 8 cells in series only one has to fail or have lower voltage and leaks gas or other bad things happen. Please don't do this!

You could use 18650 powertool cells instead maxwell or samsung ones they are rated for 20A constant current and have "save" LiNiCoO2 chemistry.
the disadvantage is capacity with those cells only 2000mAh, but those are real 2000mAh at 10A discharge current. your 22650 may have 4000mAh at 2A discharge current and most likely 2500mAh or less at 10A.

also powertool cells have very high quality I recommend Maxell INR18650PE2 or Samsung INR18650 20R

maybe you should also add a fuse for the battery current because it will raise when the voltage drops and it will do that pretty fast when using so much cells in series.
 
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I tested my cells with a 0.5 Ohm load.
They test at ~5.5 Amps dropping to ~3.5 volts.
I tore one cell apart and found no PCB.
I hope I get the new cells soon!!
HM
 
ARG said:
Typically you're safe up to 2C.

Be careful with those ratings though, 6300mAh seems fishy. I would not try to draw more than 6A from those cells without knowing more information about them.
Click to expand...

I agree with the 6 amp limit.

It depends on the internal resistance.

I like the new Panasonic "PF" 18650 cells which are rated for a solid 10 amp discharge, and have 2900mah.

Internal resistance is a very low 22 milliohms !

LarryDFW
 
Larry --
Thanks for the info. These cells originally
powered the laser well. Now they limit at
about 5 amps.
The new cells I ordered are rated at 20 Amps!!
We'll see ----------
HMike
 
HMike;

Let us know how the new Samsung cells work.

You can test the internal resistance with your 0.5 ohm load for voltage drop.

LarryDFW
 
yesthisissean said:
10 amps??!!!!?? That will kill you
Click to expand...

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