Voltage tolerance of ESP32 C3 Mini 1 pin

[Mynthan]

I want to know the Voltage tolerance of ESP32 C3 Mini 1 pins. I am planning to make a charge sensing circuit. In order to do that, I am attaching the pin of esp32 c3 mini 1 to battery (3.7V Li ion battery which max voltage can be around 4.1V) by a 100k resistor. Would this damage the pin and MCU. IS there any alternate ways?
BAT_C
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[R11] 100kΩ
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+-------> GPIO20
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[R12] 100kΩ
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+-------> GPIO10

[Sprite]

Probably not. Technically, you're not supposed to put a voltage of Vcc+0.3V on any IO pin of the chip. In practice, the chip has ESD protection (snapback devices, iirc) that will short the excess voltage to Vcc, and given the fact that you're limiting the current to a miniscule amount, you should be fine.

One thing to note, though, is that I see that the 'ground' of your resistive divider is another GPIO; I imagine that you did this to not have the divider be a drain on power when the chip is off. However, due to the aforementioned ESD protection, the chip will still drain power to Vcc, even if it's off (Vcc is grounded), so I'm not sure how much power you'd save.

[Mynthan]

I put the GPIO as ground so that only during a portion of time I will set it to low and measure the voltage at the other GPIO. Otherwise, I want little to no current flow. This is the situation that worries me as during this effectively the battery voltage is directly given to the GPIO (as only 1 resistor is in between the Battery voltage and GPIO pin).