Lithium Ion 18650 Internal Resistance And Cell Matching

[@bryancunningham1095]

Video great, also for matched packs you mentioned internal resistance, voltage, manufactures specs capacity also want to include type cells like NCR18650A verses NCR18650B since these can have a quite different chemistry and on the capacity I would check that using your chargers not depending on only the manufactures specs as you have mentioned in your video. The one big thing with these types of sliding mechanics are getting the best contact to the battery poles trying to eliminate this variable when the charger determines internal resistance, some of the best aftermarket use a small spike at each end of the sliding mechanism to help get a good contact, they might even be using tungsten or iridium tipped spikes so battery arcing when placing and removing the cells don't corroded the contacts. One last point if any batteries leak out the corrosive electrolyte (Lithium Hexaflurophosphate or LiPF6) this must be cleaned very well and to nuteralize the salt or the slider strips will corrode, also this electrolyte is flammable. Note discharge these batteries and dispose of them correctly.

[@1nformatica]

Hey thanks! Good information to share, thanks. Have a great day!

[@fankiehsieh5941]

What’re the benefits of matching cells by impedance or by voltage before making pack? How do people chose one over the other? Also heard some pack assembler do capacity balancing? Why?

[@1nformatica]

It comes down to personal choice. I want maximum current so I select by IR first then voltage. Clearly the cells to make a pack should also be of the same capacity. Balancing is normally done by using a BMS that has that feature built in. It measures the cell voltage and when it reaches a pre set maximum a load is applied to the cell to stop it overcharging. Thanks for watching, have a great day!

[@fezdk]

The internal resistance is so far from eachother, when comparing the charger and the discharger... so which do we trust.

[@1nformatica]

Both are correct! A cell's Internal Resistance (IR) is a factor of chemistry. It varies with state of charge, internal and external temperature and other factors. The important thing when building packs is that the cells IR and resting voltage are as close as possible. If you make a pack with mismatched cells it will go out of balance quickly. Packs made with matched cells will often end up closer in IR and voltage after being cycled a few times.

[@GearGuy]

Any thoughts on the this unit (VC4 Plus) vs. the VC8? I like that the VC8 has 8 larger slots and also seems to have most of the capabilities of this unit (though no output during dis-charging), but it does have USB-C and QC3.0 input/charging capabilities. I am just not sure if there is something the VC4 Plus does (beyond the output option) that I might be losing by getting the VC8.

[@1nformatica]

From what I can see you are correct. The only difference is more slots and no USB out.

[@felxstak7728]

I wonder if it is possible to measure battery internal resistance with a mutimeter and a standard 1Ω resistor.

[@1nformatica]

I don't understand how that would work, can you explain?

[@fkfontaine]

Of course. You put the resistor on the battery and check the voltage difference. Then use the formula to calculate the resistance. check this video kzbin.info/www/bejne/l6eWaZx4rciCnbM

[@MCsCreations]

Really nice work, my friend. 😊 That charger looks great!

[@1nformatica]

Yes! A very useful addition to the workshop.

[@richardachilles5601]

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[@musaking5991]

@Richard Achilles Yup, I've been using Instaflixxer for months myself :D

[@practicalguy973]

Battery have the highest resitance at empty and full but not in the middle. So checking internal resistance should be at both full and empty I would think. Pretty easy to do that with the charger you have!

[@1nformatica]

That is a very good point. Thanks for sharing. For selecting / matching cells I'm most interested in the worse case which would be charged or discharged.

[@practicalguy973]

@@1nformaticaThanks, I've been researching this for a couple days now trying to find an accurate charger than can show the internal cell resistance but I decided that I'm better with a 4 wire AC pulse battery resistance meter. I ordered the YR1035 meter just now. I think this will give me more accuracy with difficult cells and I can probe other larger batteries in place like the batteries in my UPS with it so it adds more options for long term projects. Anyways good luck with your battery packs and health!

[@1nformatica]

Looks like an interesting device. I found a good review here : lygte-info.dk/review/InternalResistanceMeterYR1035%20UK.html Mabe you can post a video of your tests.

[@1nformatica]

@@practicalguy973 This may help with the Chinese : kzbin.info/www/bejne/r4K8g5dpi697r8k

[@losien1]

@@practicalguy973 hello, i also have a charger with IR measurement, TEC-06 and they also show different values. Same like u was thinking about buying YR1035+ just to get the correct value. Did you get yours and compared them against each other? How far tec-06 is from yr1035? Thanks in advance!

[@TiptreeJams]

An interesting topic as I have an old laptop battery pack I was going to take apart to see if any cells are salvageable. I note that your voice only appears to come out of my left earpiece whereas the sound for the Like popup comes out of both i.e stereo.

[@1nformatica]

Sorry for the audio quality, had a few equipment issues. Hopefully it is still understandable.

[@diydan6045]

What is reasonably closely matched 30 mohms or 10 mohms

[@1nformatica]

I mean they should be closely matched to each other when making up a pack, so within 1 mohm. For example a pack for my EDF RC model plane has 3 cells all at 5 mohm because it draws a lot of current. A "normal" plane can use 10 mohm cells as less current needed. Maybe for a torch 30 mohm is OK. So you see it means closely match cells for a particular application. Thanks for watching, have a great day!

[@davidhsieh2761]

Weird, listening with headphones and there's only audio in the left channel

[@1nformatica]

Sorry for the audio quality, had a few equipment issues. Hopefully it is still understandable.

[@daftnord4957]

i turned on mono audio in windows

[@FM-fn7eo]

i have LiitoKala Lii-500 when is better to measuring internal resistance ,when is full charged or when is discharged ? it is very different value like 10-90 .

[@1nformatica]

Internal resistance is effected by many factors including the state of charge (SoC), temperature and current. Personally I check after charge is complete. What is important is cell matching so whatever method of measuring IR you choose make sure it is always the same. See www.researchgate.net/figure/Internal-Resistance-Change-Curve-in-Charging-discharging-Process-of-Batteries_fig4_291195631 Please consider subscribing if you have not done so already!

[@AlexandreLollini]

Wow, i should weight the cells too ... because for the moment I eliminate cells that have lost more than 0,06 V in a month and those with higher than 75 mOhm IR and I trust capacity tested by the seller, but here I see weight can be an important way to check if a fake cell slipped through the chain. (my application is low Amps in very big packs for the home)

[@1nformatica]

Yes, it is a quick and easy test to weed out weak cells. No point in wasting time on them.

[@GearGuy]

Can the Adeaska VC4 perform all the charging and tests, etc on ANY lithium Polymer battery as well? If yes, then how does one connect the two wires from lithium ion polymer to the VC4 plus? I don’t see any ports except the slots for the cylindrical batteries... If you are not sure, feel free too post a link to a video of someone else who know how to achieve those tests for a lithium polymer with a two wire interface. Great video, but I specifucally need the charger to work on/ test both lipo cellks AND LIPO polymer batterires.

[@1nformatica]

This is only suitable for single cells not batteries. My daily charger for LiPo's with internal resistance measurement is the SkyRC e680 : kzbin.info/www/bejne/gXPOc6ipYriWf5I

[@GearGuy]

@@1nformatica I think I may have stated the question incorrectly: What I mean is that I have laptop batteries composed of six individual Lithium Polymer Cells (so each one is a single 3.6v/3.7v cell, just in polymer format). So I want to separate the six polymer cells and match them by capacity and impedance to build a multi-polymer cell battery... just like what you are doing here, but with polymer cells instead of cylindrical lithium 18650 (etc). I just can’t see how to use the VC4 Plus to test/analyze the polymer cells as they would end in two (positive/negative) leads (that I would solder on) ... I could of course attach a two hole JST connector, but again, there is no port on the VC4 plus to accept a JST female plug from a single polymer cell. Specifically I want to use the VC4 plus to find the impedance of each individual (and separately wired) polymer cell.

[@1nformatica]

@@GearGuy The VC4 is designed only for cylindrical cells. There are no ports to connect wires. You would be better off getting a stand alone meter like this one : bit.ly/PZEM015 Battery Tester DC Voltage Current Power Capacity Internal And External Resistance

[@GearGuy]

@@1nformatica Thanks, I think I might get both since I have quite a few of each and the features of the VC4 Plus should make dealing with the cylindricals a lot easier. Thanks again for all the help and quick replies.

[@1nformatica]

@@GearGuy Great! Let me know if you have any other questions.

[@rowanballinger3690]

Once you have tested your batteries and sorted them for there internal resistance. Do you sort the cells internal resistance in parallel or series?

[@1nformatica]

Hi Rowan, when I build a pack I try to match as closely as possible the IR of cells both in series and parallel.

[@rowanballinger3690]

1nformatica great thank you

[@Tefelucky]

This kind of device read defferent kind of internal resistance of the same cell in different charging port in the same charger...😂😂

[@1nformatica]

That is true of any device that claims to measure IR. You will always get different results. However, the important thing is that you can COMPARE cells. It does not matter whether they are 1, 10 or 100 milliohms provided you build a pack of the same. Thanks for watching, have a great day!

[@nekrosantenabu6577]

Cómo me gustaría que doblaras al español este vídeo. Mi inglés es muy básico y hay tan poco en español sobre este tema... Yo siempre le di mucha importancia a la resistencia interna... Ya en los 90 cuando corría con mis baterías Sanyo seleccionadas por LRP, con una baja resistencia interna los picos de alta intensidad eran posibles! Saludos y gracias!

[@1nformatica]

Gracias por ver el video. Puedes activar los subtítulos y usar el ícono de configuración del "engranaje" para generar automáticamente en español. Si tiene alguna pregunta específica, por favor pregunte.

[@kermets]

Hi, when you test for resistance in the two battery’s that are welded in a pair is there a formula to calculate for each cell ?

[@1nformatica]

As far as I know there is no way to do that. I try to use cells that have been paired since manufacture so they will be well matched.

[@kermets]

Cool thanks....I didnt want to un join some but we have to learn.... the ones I tested in pairs gave a reading of say 80mΩ but when pulled apart each cell was say 170 and 165 each cell....so just over double once pulled apart.

[@nooruddinali8522]

Yeah just multiply the resistance by 2 as pack of 2 cells are in parallel..when resistances are connected in parallel they decreases and when resistances are connected in series then resistance increases

[@rajeshattuluri8760]

Can guide me for preparation battery pack for my ev scooter I have purchased batteries

[@1nformatica]

I have a video where I repair an e scooter stem battery : kzbin.info/www/bejne/mpWZi6prgdx6bpI I have never built one from scratch but I am sure if you search KZbin you will find many guides. Thanks for watching, have a great day!

[@sickvic3909]

Got this for res. test ZB206/ directions translation is impossible for normal humans to understand. Any chance of help?

[@1nformatica]

Google is your friend! syonyk.blogspot.com/2016/01/zb206-battery-tester.html

[@slonktonkster9680]

Audio mix is left only FYI

[@1nformatica]

Thanks, a problem with the microphone connection. Thanks for watching, have a great day!

[@cbic9806]

where is the tester board from? Thanks

[@cfzone8685]

Here's a one similar to the one he's using: www.banggood.com/1_2v-12v-Battery-Capacity-Meter-Tester-For-18650-li-ionlead-acid-Battery-p-1112859.html?rmmds=myorder&cur_warehouse=CN

[@AndyShell]

Ive been wondering on this for a long time. i keep them in pairs and use battery holders in 7s 32p (448 cells per wall) check out my videos. I've avoided this topic for a year but now that I've solved my other design issues I'm starting to tacking this. I'll check out your other videos and see. Thanks for your hard work!

[@4lxAnd3r]

Did you have a polarized filter on your camera? :P

[@1nformatica]

Yes! Well spotted! That type off display is difficult to record clearly.

[@4lxAnd3r]

@@1nformatica Nice :D i was just curios if the display was naturally this 'rainbowy',the cool polarized plastics internal stress rainbow :)

[@1nformatica]

Yes, it's very pretty!

[@curtisj2165]

Don't forget those cells are not brand new, so you won't get the same mah rating

[@1nformatica]

Thanks. I guess that is why I am testing them!!

[@LemonDropsMedia]

my right ear is feeling a bit lonely now

[@1nformatica]

Please accept my sincere apologies, a technical fault. Note that the person responsible was fired! Back in the day we called it "mono"! Hope you enjoy my other videos.

[@musicsub7684]

thanks from indonesia

[@1nformatica]

Thanks for watching, I hope you find it useful.

[@chimeranzl9147]

very muffled audio?! cannot hear.

[@1nformatica]

Sorry for the audio quality, had a few equipment issues. Switch your sound to mono and hopefully it is still understandable. Please consider subscribing if you haven't done so already!!

[@chimeranzl9147]

@@1nformatica already subbed :-) thanks for the quick response.

[@vk3zn]

i would not trust your charger i got the same charger had it for 1 day second day it shows usb everywhere 10 seconds later goes up in smoke looks nice but crap waiting for a refund

[@1nformatica]

Sorry you got a bad one. Mines is still working well. Please consider subscribing if you have not done so already!

[@MikeAustin2012]

Great video, thanks for the useful info. I am not making fun of you but, please, I guess millie ohm is technically correct, maybe? But please call it Meg-Ohm. I'm an old guy so maybe they changed it? They used to call a cycle, Cycles or Kilocycle or Megacycle They changed it to Hertz, out of respect for the man that invented it, discovered it?. That was hard to get used to but I usually get it right, after 50 years. If they changed the nomenclature to mile-ohm, so be it and I am wrong. It just sounds like fingernails on a blackboard to me. Sorry, didn't mean to interrupt. What you are doing is more important. Hows that charger/meter? I just bought the Opus C3100 now I see this? It looks great! I cant win for loosing!

[@1nformatica]

The tester works well and I specifically chose it as it has the internal resistance measurement. The prefix "milli" has, since 1795, been used to denote one-thousandth part. So the milliohm is 0.001 Ohms (mΩ). Lithium cells need to have a very low internal resistance to be able to produce high currents. Megohm is of course 1,000,000 Ω. If a lithium cell had an internal resistance of 1 MΩ then the maximum Amps you could draw would be 4.2 Volts / 1,000,000 Ω = 0.0000042 Amps or 4.2 micro Amps.

[@evanleebodies]

I wish there was an effective way of making a pack with wildly mismatched cells

[@1nformatica]

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