The battery of Quest 3 accounts for approximately 20% of its total visor weight. - UploadVR

Quest 3's Battery Makes Up Only Around 20% Its Visor Weight

The battery in the Oculus Quest 3 takes up a significant portion of its internal space. A recent teardown revealed that the battery weighs just 64 grams, making up only 16% of the headset's weight without the facial interface and straps. Removing the battery from the visor alone would not result in a dramatic weight difference. However, moving the computing hardware off the visor could make it lighter, although this would be more complex and require a larger and thicker compute unit. Other advancements like lighter displays and optimized chipsets could contribute to reducing the weight of future headsets. While the Quest 3 is not significantly lighter, its thin design makes it feel less cumbersome on the face. Visit UploadVRQuest for more details on this story.

Source: https://www.uploadvr.com/quest-3-battery-weight/