hi, im new here...
Just had some thoughts on this as it seems interesting.
How about using a computer PSU to run the nichrome wire... i reckon you would need quite a bit of battery to keep it going for a long time and your average PSU will kick out 200W all day long no problem...
Another problem with using lithium is risking over discharging them... if they are rechargeable you kill the number of cycles they will hold a decent charge for quite rapidly... if they even take a charge at all after an over discharge...
Also a little googling leads me to believe that an AA lithium battery from energiser holds 2.9Ah so to last 9.2 hours the 2.9Ah lets for simplicities sake say 3Ah battery last again for ease 9hrs it would have to be supply a third of its capacity per hour to last the 9 hours... in other words 1A...
So what rubbish is this newbie gassing on about? well what im saying is that 3Volts * 1A = 3w...
I have had way too many beers so my calculations *may* be completely off.. im trying to remember school lol, in no way am i putting this idea down but i think the power supply is a little unrealistic...
um so hello... and dont think im a complete arse based on this post.. cus it was reading this thread that made me sign up in the first place!