Quote from the article:
“Starting from the rear of the case, we first removed the screws holding on the battery compartment cover. This revealed the Li-ion rechargeable battery, with a discharge capacity of 850mAh, which was marked “Made in China” but with no manufacturer name. The Nintendo DS will operate for up to 10 hours from a full charge. The Game Boy Advance SP model also runs for up to 10 hours from its internal Li-ion rechargeable battery, but battery capacity is only 600mAh. The higher power consumption of the DS is probably due to the additional display and the onboard microcontroller, with two central processing unit (CPU) cores.”
