cells charging with 18650 charger

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stiplanet

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hi alli dont know my last fil was closed.I would like to know if I can chargemy cells with a simple 18650 chargerbefore testing them in the opus charger? just to save time, thank you.
 
Yes you can but with same current the time it takes is the same ;)
 
I think what stiplanet is saying instead of a complete charge-discharge- charge cycle. He wants to charge+2.5v cells in a 18650 charger while he is testing other 18650's in the Opus.

later floyd
 
Yes, you can certainly dedicate youranalyzing chargers to the discharges and use other (cheaper) chargers to do the charge.

But for the capacity results to be comparable try to use chargers that terminate with the same voltage and same termination current (else you may end up comparing apples vs. oranges since one charger may do a much fuller charge than the others).

See e.g. Battery charge termination test to get an idea of how much effect on capacity is caused by variations in those two parameters.

For rough first level sorting such variations may not matter much, unless you have the bad luck of getting some chargers with extreme voltage calibration differences and/or different termination currents, e.g. if one terminates at 4.25V,100mA and another at 4.15V,200mA, where the linked graphs show that the first charger may charge an NL166 12% more, and an PA18650 7% more (generally the differences will be higher for unhealthier/smaller cells due to their higher IR).
 
thank you all for your advice, I already have 5 opus BT310 c. and I find the process a bit slow, I have 3000 cells to test, either I increase the number of opus charger?or if you can advise me another charger .
thanks best regards.
 
stiplanet said:
thank you all for your advice, I already have 5 opus BT310 c. and I find the process a bit slow, I have 3000 cells to test, either I increase the number of opus charger?or if you can advise me another charger .
thanks best regards.
Click to expand...
5 OPUS x 4 cells = at least 20/day = 150days. I only have 3 OPUSs and am nearing 10,000 cells. Agree that 10 or 20 OPUSs will shorten the thru-put :)

One thing I do is go for the same cell type per battery(14s100p) so I know the cells are compatible chemistry up frontand if they are from the same 'source', they will likely be in similar testing range in terms of IR and mah. This let's me test for 4 weeks (to get a leading self-discharge window)and then start building packs in parallel with the rest of the testing. Also build the shelves/cables etc. This helps shorten the overall process so that battery construction is finished 4 weeks after the testing is complete.
 
Dont mix testers. Use one tester so you dont have to worry that much about the results.

I have 10 opus. Thats 80 cells per day.... You should be able to do 40 per day easy ;)
 
I do so too, pre-charge the cells at cheap chargers while testing another lot of already fully charged cells in some Liito Kala

image_lehvwt.jpg


I really like the XTar VC8 8-slot charger (middle, left), but they are not really cheap and handle a maximum of 300mA per slot, so I added some super-cheap chinesechargers (top row)

10 independent slots each at 0,6A cost round about 10 - 11 USD incl. shipping

image_tkzmwb.jpg


Phomax 10 slot LiIon charger (the same from brand GTF)


image_vtuhiu.jpg



image_kmsckq.jpg


quality isn't the best and I had already three defective charging pcbs,
but got three new chargers send out, took the bad pcbs out, replaced them with good ones and now have too functional chargers = 20 slots extra.
Should not be your first-use charging device but for fast bulk charging it's perfect - for me.
Oh, and they can do 0V reactivating as I tested, that's the first picture
 
You can quickly weed out bad cells by testing for -
- IR (internal resistance)
- cells under 1V (recycle these, not recommended to use for powerwalls, maybe ok for torches, etc)
before charging.
 
good evening the family I come back with a concern, I selected recharged cells, I retained only the cells which have 2000mah and more. I have had 900 cells for the moment, is that with 900cells I can make a big battery? also I have 300 cells below 2000mah to 1500mah that I would like to use for training, with that is 300 cells I want to build a 12v battery as a single block, so I need your advice and help to achieve it, with the necessary equipment, type of bms, and configuration of cells thank you all.
 
stiplanet said:
good evening the family I come back with a concern, I selected recharged cells, I retained only the cells which have 2000mah and more. I have had 900 cells for the moment, is that with 900cells I can make a big battery? also I have 300 cells below 2000mah to 1500mah that I would like to use for training, with that is 300 cells I want to build a 12v battery as a single block, so I need your advice and help to achieve it, with the necessary equipment, type of bms, and configuration of cells thank you all.
Click to expand...
Are you sure you want to create a 12v battery? 18650 lithium-ion voltage ranges just don't make a proper 12v battery. 3s is too low (9v - 12.6v)and 4s (12v -> 16.8v) is too high. 24v(7s)or 48v(14s)use of 18650(s)creates a perfect voltage range for regular 24/48v equipment/uses. You can do24v -> 12v buck converter to get a proper 12v at a reasonable price if your power requirements are<80a.
 
thank you for your answer, I need a battery with a voltage of 13.20v maximum, I want to make a battery in a single block, if the voltage does not exceed 13.20 it's good, what configuration do you recommend? I also have a buck converter, my energy needs will not exceed 80A
Total cells is 200 cells 1800mAh
THANKS
 
As said 3s is 12.6V max. And 200 cells is 66 cells per pack in series. 1800mAh sounds like 2nd hand cells tested rather low? I wouldnt stress them above 1A per cell if thats what you tested them at.
On other hand if you tested them with a Liitokala that only do 0.5A you have limited your max current to 33A.

If they are new High power cells the scenario is different but above is based on best practice for laptop cells to make sure we stay within limits that makes it alot safer.

LiFePo4 cells going 4s suits better a 12V voltage range but then we talk about different cost.
 
these are old cells test with opus 310
so you recommend me a 3s system? if yes i will try 3s system
you can give me 3s or 4s system diagram?
thanks for your helps
 
3s suits better but as said its max 12.6V....

Battery1 -> Battery 2 -> Battery 3...

Thats 3s ;)
 
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