A betavoltaic power source for transportation devices and applications is disclosed, wherein the device having a stacked configuration of isotope layers and energy conversion layers. A memory embodiment includes a nanofin transistor having a first sourcedrain region, a second sourcedrain region above the first sourcedrain region, and a vertically-oriented channel region between the first and second sourcedrain regions. The rotational housing may be adapted to hold an electrical cord. Exemplary plasticizer compositions include one or more of dimethylisosorbide, propylene carbonate, methylbenzyl alcohol, glycerol carbonate acetate, glycerol carbonate ethyl ether, and mixtures thereof, optionally in combination with triacetin.