The following info comes from a Game Watch test
- original GamePad battery was 1500mAh
- large-capacity battery pack is about 1.7 times stronger at 2550mAh
- original had an operating time of about 3-5 hours
- new one is said to last between 5-8 hours.
- test had the GamePad’s brightness at maximum, all power-saving methods were turned off, vibration was turned on, and Monster Hunter 3 Ultimate’s opening movie was played on full blast
- GamePad lasted 5 hours and 12 minutes with the new battery
- original battery would last about 3 hours in this state