I'm making a laser. This diode on ebay http://bit.ly/c3sXcE The laser is a very bright 100mW green laser, which draws 3.7V @ 650mA. It has a 60 second duty cycle. I would be using about 4 3.7V rechargeable lithium cells rated @ 2500mAh each. So 10,000mAh with a 650mA draw would run the laser for how long? I'm sure it's an easy conversion, but my calculations aren't working out.. 15 hours? Thanks!