USB powered "fake" battery pack adapter?

[pier4r]

(04-15-2018 09:56 AM)Massimo Gnerucci Wrote:  What about something like this?

Those are a lot of cables to connect on the back of the calculator, but that is exactly the right track! Thanks for the link.

What I was thinking was exactly like a pack of 2,3,4,...,N batteries connected to each other with one plug for a micro usb cable to get the energy constantly. If they recharge, even better, but it is not necessary. They can be also dummy that fits the battery compartment.