How to Test Battery Capacity without Special Equipment

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[TLamparter]

Puts "without Special Equipment" in title, proceeds to test batteries with special home-made tool.

[MrCreepermax]

The second i saw a breadboard I knew special equipment was needed hahahaha

[Shadow_of_STLKR]

In short.
Li-ion cells with weight above 40g have capacity more than 2500mAh
40 to 30g usually has 2700-1500mAh
and less than 30g 2100-300mAh

All type of cells should be measured by discharging it with stable current and stop when voltage hits min safe Voltage specific to type of cell (li-ion 2, 9V, li-po 3, 1V, ni-mh and ni-cd 1V)

[offgrid]

Definitely helpful! So you confirm discharge to 2, 5 to rate capacity and the formula's make the process ez to understand. Thank you!

[aquarius]

Great video. Keep up your good work. Nominal discharge capacity is linked to discharge current & discharge cut off voltage. Discharging a battery with higher or lower discharge current will result in lower respective higher capacity. If discharging a 2000 mAh rated battery with 1000 mA will last 2hrs, discharging the same battery with only 500 mA will last longer than 4 hours.

[nattsurfaren]

Can you determine the capacity just by measure the time it takes to recharge, the amp and voltage you recharge with? How long time did it take to recharge the fake battery vs the samsung?

[BillJutz]

They were only off by 1 Zero, if it said 880 it might have been close to reality.

[princewillwp]

What about the life cycle, how can I calculate that?

[Philjj]

Fun fact 18650 stands for 18 mm wide and 65 mm long, button batteries 2032 stands for 20 mm wide and 3.2 mm thick and so on and so forth.

[LostOnTheLine]

"How to test capacity without special equipment"

Okay, this sounds nice, exactly what I'm looking for...

"the first thing you need to do is get a precise scale..."

But I'm not a dealer or a scientist, I only have a scale that measures in LBs, nothing that can give me exact grams, like most people... But it's okay there's more

"Next you need a complex special device, or build one out of parts, that will draw exactly an even 500mAh consistently"

So you mean I need some more special equipment?
You're saying the way to test capacity without special equipment is to buy some special equipment & either buy some other special equipment or build your own special equipment...

[offgrid]

Is it possible to discharge a 18650 at .5 amp down 500 mah and extrapolate the full capacity from that? I have over 100 battery's in my e-bike individual cradle system. Also can you use the same procedure for the entire battery pack?

[depopa]

"2 dollars only" * 30 bucks shipping* i love it

[freewheelinfranklyn]

That's a huge difference and an even bigger difference from what's printed on the fake battery! Thanks for the demonstration. I would like to test all the cells in a dead ebike battery but this method would be like a life sentence to me. Is there a quicker method that I could use?

[frv]

I post same questions under this video also since I didn't get answers under the other video.

Why is not Wh (battery capacity?) calculated with max full charged voltage? For example if an electric kickbike's (Sealup Q8) battery (38km range on a good day) is rated as 48V21Ah (48x21=1008Wh) but it's full charge voltage is 54.6, so why not calculate it as 54.6V x 21Ah = 1147 Wh?

I have a kickbike Q8 battery (Samsung cells purportedly) rated as 48v21ah but it soaks only 877Wh according to power outlet meter. Should it be soaking 1008Wh or 1147Wh, or is 877Wh correct? I also have another battery from (Aliexpress) Liitokala (tested 27km range) rated as 48V20Ah (48x20=960Wh or 54.6x20=1092Wh) but it soaks only 698Wh (it's more like 15 or 17Ah?). So am I scammed or it is normal? I complained to Aliexpress about it LiitoKala battery, that it should be at least 835Wh in it if it is 20Ah but they ask for more proof. I already showed with power outlet meter how much it soaks, it is 698Wh and showed my other battery soaks 877Wh (for comparison). Aliexpress supports vendors lying about real capacity of battery. Idk how I can prove to them that LiitoKala is not 20Ah battery (more like 16Ah).

I also bought on Aliexpress a 48v24ah battery called Aimjin but it only charged to 53v (not 54.6v) and from empty to full only soaked 340Wh which indicates its capacity is 7Ah. It also became warm when I used it which indicates it is an old tired battery. But I paid for it near same price as for new battery. Scammed.

[Soothsayer]

Thx. for the video. Can you explain the following please?
may i know why you said the batteries would discharged completely when it reached 2.5 volts? How do i for 1.5 volt batteries. Please correct me if i am wrong, i was thinking the voltage will be completely depleted to 0 volt? when i buy batteries from a shop what should i be checking to see the capacity? I have a small model plane and i find different batteries provide different flying times. Is it because of the
* different wind conditions causing it to draw different currents
* is the the acceleration that is causing it to draw more power
Let me know your thoughts please?

[syaduinotech]

thanks for the idea sir, is there any video that you create mention using mechanism to record it beside manual (just curious, maybe using arduino or else). Tq sir in advance

[juanmf]

Couple of questions:
1) Does your dummy load adjust resistance as V drops to 2.5V?
2) how did you determine 2.5V is the “depleted” voltage target?

[mirceaatat]

For all the guys who tslm about the "epecial equipment"》 i hope you've learned something today.
And you can do the same thing with any load that you know exactly the consumption/hour

[ddistrbd]

Well done, I learned so much watching this video. thank you.

[__-hhgt]

Dramatically fantastic. You are exceptional expert. Greetings from Saudi Arabia.