Last night i did an experiment with a halogen bulb, rated at 12v 100w (8.33amps) dc. The exact model is this: http://inpcars.com/spotlights/motortrendmts43707-i.jpg I used to turn that bulb on, 3 serial batteries 1.5v "aaa" @ 0.4ah = 4.5 @ 0.4ah (1.8watts), and it turn on a little bit dimmed, then I used the lithium battery from a cellphone rated at: 3.7v @ 1.050ah = (3.89 watts), and it lit slightly stronger. Then I put the "aaa" batteries in parallel to get: 1.5v @ 1.2ah = 1.8w, but I didnt turn on not even weak (did I do something wrong? or something was loosen in the wires)? I have 2 questions: 1. How could tiny batteries provide (at least) energy to power such a high amp demanding bulb? 2. In this case, what factor would make the bulb to be much brillant? a higher voltage? or a higher amperage? (or even whatever that puts a highter number or watts)? This is still a little confusing. :( Gracias in advance.