running bot off car battery?

[Andy A.]

I may be wrong, but I am quite sure this wouldn't work. AA's (dry cells in general) can't deliver high current draws like the kit battery. They are made to give a steady low draw for a long time, not a 100+ amp draw, then 20, then back up to 100 with some 150 spikes just for flavor. I suppose we could do some tests and see what a AA short delivers, but I imagine it will be very, very low compared to what we need, even when multiplied by 56. Maybe this is already documented. I can't find any data, but everything suggests that if you do put high draws on dry cells, they very quickly derate and your 2800 milliamp rating drops. No one defines what 'high current draw' is. In any case, you would need an obnoxious number of AA's.

I ran into this problem with a model rocket ignition system I made up. Despite having 3 times (eventually 5 times) the power of a normal ignition system, it couldn't ignite 3 engines at the same time. Plenty of power, just couldn't get it to the engines fast enough. I grabbed a 2000 kit battery (only half charged) and it worked just peachy.

-Andy A.