How to check 18650 battery

We already wrote about the test on 18650 battery real capacity and how to use them to build powerful battery for different tasks. Also tested the high quality battery of this class Samsung INR18650 by as much as 25 Amps of operating current.

Now let’s see how to check the battery on the suitability for further service and whether it can still revive…

The contents

  1. Li Ion
  2. Voltage and current
  3. Control measurement
  4. Capacity
  5. For sagging voltage
  6. Using iMax
  7. Only a tester and a homemade diagram

Li Ion

I must say that the whole conversation on this page will be about the most popular today in all branches of electronics and electrics is Lithium Ion batteries.

When using Li-Polimernyh may be nuances, but if you have Nikolaeva-Cadmium,… throw them in the trash, their time is long gone.

Voltage and current

We’ll need a voltmeter and ammeter to measure voltage and current, respectively. You can use two multimeter or one special charger.

I suggest the iMax B6 Mini is better it is unlikely that something came up, or Liitokala. On both devices we have reviews.

You can, of course, for want to use just one multimeter and alternately to measure both parameters. But if so, then my advice to You is not necessary — you all know it.

Control measurement

Put the discharged 18650 battery on charge and wait. If, as the charge process the voltage cannot cross the mark of 4 Volts, then send at once in the trash, even to restore it will not work. Otherwise, it’s still about what does not speak and we still froze…

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As we move around 4V, look at capacity. If it is less than 200 mAh, then it too can be safely disposed of. With any working battery to the 4-eat volts capacity should already go for 800 mAh.

If you really really don’t want to rush, you can do a full charge and put back on charge. If the capacity for the second time will be more when crossing the border to four volts, so can be repeated many times and try to «shake» the jar.

For sagging voltage

So, the specimen is charged up to 4.2 V, what’s next? You can measure the internal resistance of the same devices that I mentioned earlier. If the internal resistance is much higher than similar workers, so, too, in a landfill.

There is nothing to measure internal resistance? Then apply Ohm’s Law for the complete chain. Connected to some load. If the voltage immediately sags below 3.6 V. a standard desktop, so, too, «HANA».

Using iMax

About Imax and all the chips, which it can do with batteries, we wrote this review on iMax B6. He may be a capacity to measure the correct way — directly full discharge and charge. And can be restored by trickle charging, plus the «swing».

Given the dense occurrence throughout different battery in our lives, I think it is worth it just to buy one.

Only a tester and a homemade diagram

Well, about that see it in the video below: