What is the maximum mAh for an arduino mkr wifi 1010?
The question is too ambiguous. Please restate your question with more information/background.
mAh is a measure of the average current a device uses over a one hour period, and to know that you either need to measure it or have some idea what the device is doing.............................
The reason is that I can't Really use its low power features.
@andrewcuse1, your topic has been moved to a more suitable location on the forum.
Can you please elaborate? Is it because your design does not allow for it? Or because you haven't managed to reduce the consumption enough?
What I mean is: What battery would you use for a normal Arduino MKR WiFi 1010 Project?
That depends on how long do you need the board to run and what is the average current of your application.
As a reference I did a few tests with an Arduino Nano 33 IoT a little version of your board. Running from a single 18650 (~3500mAh) it stayed active for around two days sending a few MQTT messages per minute over WiFi.