All Lightsabers come with a built-in rechargeable battery.This depends on RGB or Neopixel. RGB can last upto 4+ hours while on, this is because they draw a lot less power compared to neopixel.Neopixel batteries typically last up 2/3 hours, if you take care of your battery and charge using a 5V 1A you will make your lightsaber battery last a lot longer!