@ electronicsidiot : Mate, your idea makes sense. To get onto the next step, i'd like ask that wat sort of sensors shud one go for??
I wud opt for a Solar sensor interfaced w ith a Solar Charging circuit. So that when it goes in brightest of sunlight, it shud trigger the charging circuit. The maximum intensity of sunlight can be programmed to have a typical voltage level (say a threshold), so that along with a comparator, we can trigger the charging circuit (and ultimately disabling the locomotion circuit/motor drive) when the output of the sensor goes exeeds the threshold.