Apple has finally published the product sheet for September 2019.
More than half of the credit can be attributed to the big battery. For example, the XS Max has a 15 hour video playback rating while the Pro Max has 20 hours, which represents a 33% increase.
The removal of the 3D Touch layer (0.5mm) has allowed for a thicker battery. This is in addition to the increase from 7.7mm to 8.1mm of the body.
https://www.apple.com/legal/more-resources/docs/apple-product-information-sheet.pdf
- iPhone XR - 11.16 Whr
- iPhone 11 - 11.91 Whr (7% more)
- iPhone XS - 10.13 Whr
- iPhone 11 Pro - 11.67 Whr (15% more)
- iPhone XS Max - 12.08 Whr
- iPhone 11 Pro Max - 15.04 Whr (25% more)
More than half of the credit can be attributed to the big battery. For example, the XS Max has a 15 hour video playback rating while the Pro Max has 20 hours, which represents a 33% increase.
The removal of the 3D Touch layer (0.5mm) has allowed for a thicker battery. This is in addition to the increase from 7.7mm to 8.1mm of the body.
https://www.apple.com/legal/more-resources/docs/apple-product-information-sheet.pdf