A battery-operated lighting device (100) for use with any one of a plurality of rechargeable battery packs (200), each pack (200) having a pair of terminals (216) and a different operating voltage. The lighting device (100) comprises a casing (110) having first and second parts (112/114), a lighting unit (120) including a light bulb (122) provided at the first casing part (112), and a battery chamber (150) formed at the second casing part (114) for receiving at least part (214) of and locating said any one battery pack (200). The light bulb (122) has an optimum operating voltage. A pair of electrical contacts (136) is located in the chamber (150) for making electrical connection with respective terminals (216) of said battery pack (200) located by the chamber (150). The casing (110) houses an electronic voltage regulating circuit (140) that has an input (141/142) and an output (143/144) in electrical connection with the contacts (136) and the light bulb (122) respectively. The circuit (140) is arranged to regulate the voltage of said battery pack (200) down to substantially the optimum operating voltage of the light bulb (122) for operating the light bulb (122).