Oooooo brilliant thanks @parasquid.
I've got 15 resistors and created the 225 combinations to see what output voltage I can achieve (easy enough using a full outer join).
The best voltage was very low eg 2.3v, which felt too low. My assumption; at this stage; is the higher the voltage (below 3.3 of course) the better the data to understanding nuances of battery charge. I may just be over complicating things.
Now I know I can connect them in series I have loads more option.
Thanks for the link, I was using https://ohmslawcalculator.com/voltage-divider-calculator
Even if the voltage out of the divider is 2v3 it still represents the 14v max from your power supply. The only thing you'd be missing out would be the fine grained voltage changes because the interval of 0 - 3v3 would have more values mapped to 0 - 14v as against 0 - 2v3
I personally just use whatever I have and use them so I can get a prototype running, then later on adjust the components so I can improve accuracy :P
When connecting resistors in a series for a voltage divider, I also now always triple check the location of the division. Whereas with only two resistors there's just one "junction" for the lower voltage, in a series you'd have many outputs and most of them would be far above the voltage tolerance.
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