What battery is this? And where can I get a replacement?

So my lightsaber can't hold a charge anymore. I charge it for 30 minutes and I only get 2 minutes before it's dead again. It never held one for long anyways as I could charge it and not use, then a week later it was dead again. But I heard from a friend that you should remove the battery when not using the lightsaber. Allowing the battery to hold the charge. Anyways, I need a new battery. But I have no clue what type of battery this is and where to get a new one. I need help.

So my lightsaber can't hold a charge anymore. I charge it for 30 minutes and I only get 2 minutes before it's dead again. It never held one for long anyways as I could charge it and not use, then a week later it was dead again. But I heard from a friend that you should remove the battery when not using the lightsaber. Allowing the battery to hold the charge. Anyways, I need a new battery. But I have no clue what type of battery this is and where to get a new one. I need help.