Hi guys,
I am new here and still not an. engineer and have not much knowledge in Battery / electricity but have a major project I am working on and would be very happy to get some answers..

I am trying to build a machine that is using a spin motor that work periodically in set times (650 spins a day: 10 turn per minute than a few minutes rest) by a simple electric circuit.
The manufacture of the motor sent me these consumption values: Voltage: 3 - 12VDC, Current @ maximum efficiency: 0.17A. On the machines provided power supply I have the follow values: 3v / 1.2A

They also claim that when it is operated by strong 2 x AA batteries it will be able to work for around 8-9 weeks (defined amount of movements periodically in a day - around 650 turns total).
I try to find a way to operate the machine longer without any need to change the batteries every second month.
I try to look at a solution of connecting a 40000mAh portable usb power bank to it through a 'step down voltage device' that will provide it the right amount of Voltage and Ampere.
Like this one:

https://www.amazon.de/gp/product/B07WJ82KPF/ref=pp...



My questions are:
Is it true that in these settings with a 40000mAh power bank, the machine will be able to run 20 times longer that when it will when running on 2x AA 2000mAh batteries ?
Is it safe to have the machine connected to such a power bank constantly and have it stored in a close place ?

Thanks a lot for your time !