Boost voltage

[TASP]

Has anyone adapted an inductive charger setup to any HP calculators? (or any newer models come that way from the factory?)

Also, would the 'joule thief' circuitry be something to consider wiring internally to, oh, let's say an HP41 hypothetically speaking, LOL ?
My first thought was it would just be a problem with card reader operations, but perhaps a little more circuitry would help; like maybe slowly ramping the voltage from just above to just below the 'BAT' indicator voltage to make it blink, and having onboard sufficient capacitance to complete one card read. (realizing that both techniques there at the same time seems a little tricky to implement)