Here is an image for your reference of Edison’s basic parts.
Edison recommends the following: Low or flat batteries can cause a range of issues with Edison. For this reason, always use fresh, fully charged batteries in your robots. Choosing batteries: If using disposable batteries with Edison, only ever use alkaline batteries. (These are the most common standard AAA batteries you will find in just about any shop.) If you are using rechargeable batteries with Edison, only use nickel metal hydride (NiMH) rechargeable batteries. Never use lithium rechargeable, heavy-duty disposable, super heavy-duty disposable or carbon zinc batteries [2 p.12].