'Use ADS1115 to measure voltage

I would like to measure the voltage of each element of a battery pack made of 18650 cells.

I use an ADS1115 to get the voltage. My problem that when I measure an element each time everything is ok but as soon as I try to measure several elements at the same time on the battery the voltage values ​​are completely wrong.

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I am in differential mode

I would like to measure A0 - A1; A2 - A3 but I can't if both 18650 cells are connected together.

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Solution 1:[1]

From the datasheet:

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You can see by looking at the absolute maximum allowed analog input voltage, you are exceeding the range of the device. Two of those cells in series is outside that range, and you have likely damaged the device.

Looking just a bit further down at the recommended range:

enter image description here

You shouldn't be going more than 6.144 V across the inputs. Two 18650 in series is ~7.4 V nominal, but can be as high as 8.4 V!

Also note that you should not be going outside the supply voltage range (which you haven't specified).

Sources

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Source: Stack Overflow

Solution Source
Solution 1 evildemonic

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