Testing the 18650 batteries
To build the cells of this diet for outdoor astrophotography setups, we sort the 18650 batteries. (the planned assembly is 6 sets of 3 batteries in parallel: 6S3P).
As a reminder when you make up the cells (several batteries mounted in parallel) they must be similar, because it is the one with the lowest performance that will give the capacity of the cell.
Once their characteristics are known, we will pair them 3 by 3 depending on these.
Step one: battery testing
We will use the 18650 lithium battery tester, ZHIYU® ZB206:
It's available here for less than €9
This one will give us:
- The battery capacity in Ah,
- The energy provided Wh ,
- The voltage of the V discharge tray,
- As well as internal resistance.
- We will note for each 18650 batteries, their characteristics in view of the sorting.
The intensity chosen for the discharge will be 0.10A, to match those of future use.
When powering the tester, use the S– and S-no keys for the discharge value. Once it is set and the battery plugged in, press the SK button to start testing.
The buzzer will alert you to the end of the test. Then just scroll through the values with the S– and The S- buttons.
As far as internal resistance is concerned, connect the battery to the BV plug, respecting the polarities. The value of internal resistance will be displayed when the tester is powered up.
What's next tomorrow…