Alternative LEGO Rechargeable Battery Box (8878) – Green Gecko Workshop
Amazon.com: DooQi CADA Technik Power Function Kit for Technical Cars, Including 3 Motors, LEDs, Battery Box and 2.4 Ghz Remote Control (Compatible with Many Models Such As Lego CADA) (S059-001) : Toys
Batteries and Battery packs
Amazon.com: LEGO Power Functions Train Motor kit Including IR Receiver, Remote & Battery Box : Toys & Games
LEGO Battery Box 4.5V 6 x 11 x 3.33 Type 3 for connectors without middle pin | Brick Owl - LEGO Marketplace
LEGO Power Functions - M Motor 8883 and AAA Battery Box 88000 Review ( PF ) - YouTube
LEGO LEGO Functions: Power Functions Battery Box (8881) for sale online | eBay
LEGO Electric 9V Battery Box 4 x 14 x 4 with Dark Gray Base (74650) | Brick Owl - LEGO Marketplace
The new Powered Up battery box | Brickset: LEGO set guide and database