"Wii Fit" is an exercise-related video game for the Nintendo Wii. "Wii Fit" was introduced with the "Wii Fit" Balance Board. The Balance Board is placed on the floor and stepped on. The Wii detects your movement and reports it to the game. In "Wii Fit" the balance board is used to determine your weight, and to count repetitions of steps, push-ups, etc. The Balance Board typically requires four AA batteries. You can easily go through a lot of batteries with the Balance Board, so using a rechargeable battery is a smart idea.
Purchase a "Wii Fit" Balance Board-specific rechargeable battery pack. The Balance Board does not include rechargeable batteries. These can be purchased at your local video game retailer or online.
Charge the batteries according to the instructions. It may take several hours for the batteries to fully charge.
Remove the battery cover on the underside of the Balance Board. Remove any batteries in the device.
Place the rechargeable battery pack in the battery slot. Make sure the "+" and "-" signs match up. The rechargeable battery pack may include an attached battery cover. If not, replace the Balance Board battery cover. Once inserted, you can power on the Balance Board and sync it with your Wii.