Using 4 (used) NiMH AA batteries fully recharged provides the LED with 3.6 V at 686 mA, which is over its rating.
With 3 Ni-MH cells in series, the circuit draws 3.14 V and 243 mA, so very close to the ideal 1W rating.
before | after | |
---|---|---|
Batteries | ||
cells | 4 AA | 3 AA |
chemistry | alkaline | NiMH |
capacity | 1800 mAh (x4) | 2850 mAh (x3) |
voltage | 1.5 V (x4) = 6V | 1.2 V (x3) = 3.6V |
resistance | 0.15 Ohms (x4) | 0.02 Ohms (x3) |
rechargeable | no | yes |
Lamp | ||
Technology | incandescent | LED |
voltage rating | 4.8 V | 3-4 V |