I have a small toy car that runs with a 6V (4x1,5v) pack and would like to boost the main motor(6V x 100mA) H_bridge output stage the way I can drive a 12V motor (12V x 500mA). The controller is fitted inside a chip and I have no way to access internal components.
From 0.6W motor to a 6W motor. What can the 4*1.5V batteries provide in mAh? Maybe needs an external supplementary supply and external fets or bjts for the higher power h-bridge? Or a higher voltage battery (and mAh), which presumably could require voltage regulation for the original circuit.
The toy car may look more like Frankenstein or a Mad Max vehicle when finished.