If I unplug the 12V car plug, rechargeable built-in battery of GPS lasts lt; 5 mins. I want to use it for walk-navigation. Is it possible to assemble 8x 1.5V AA batteries (12V) and power the GPS? How should I do it? Will it work? Ampere-hour considerations etc?
The battery in your GPS has failed. It should provide a few hours use. Consider replacing that battery. What you should otherwise do, to directly power it, is use four AAs in series (or 8 in series parallel) to power the GPS directly on its DC adapter input, with the 4.8 to 6V. The 3rd option, is to get a standalone trail/hiking GPS.
get a hand held GPS for walking. i use a Garmin. it has features more suited to use in the outback, like waypoints for finding your way back. real time compass for staying on direction. and long AA battery life.
