Hi Ted I spoke to an engineer at work today. He told me that LEDs range from 1.6v to 2.8v. I understood him to say that if you put a limiting resistor into the circuit, you could run a battery with a voltage higher than that of the bulb. Some LEDs apparently have a limiting resistor built in. I found this also: The Best Current Limiting Resistor Calculator for Led's Actually, if you type "led limiting resistor" into Google, you'll find quite a lot of info.