Here is how i just soldered it to a Alkaline battery.
Do you have some deceased fluorescent lamps? If Yes, then you might still recycle some of its guts to fashion some simple yet usable circuits.
Step 1: Car to portable MP3 player power supply
The first gadget is a 12 V to 1.8 V power supply, also known as step down or buck dc-dc converter. These type of SMPS (Switched Mode Power Supply) are very efficient in terms of energy loss by heat dissipation compared to the linear type (circuits like 7805, 7509, LM317, etc). This works under the principle of energy storage in a magnetic field and then just regulating the output voltage by means of duty cycle control on a PWM (Pulse Width Modulation).
Open up your lamp and look for a small ferrite core transformer (some brands might have two, so try different brands or sizes)