According to a report from the South Korean outlet, The Elec, Samsung is preparing to use the same stacking method it uses in electric vehicle batteries for smartphone batteries.

The stacking method offers at least 10% higher capacities than the more traditional roll design. If the Galaxy S22 Ultra used the stacked design, it would be able to pack a 5500+ mAh instead of the 5000mAh battery.
In addition, the new design allows phones to be thinner and lighter with the same battery capacity. The rolled design has natural swelling when the battery is charged and discharged. Because of this, batteries with this design can’t be packed as tightly.
The report mentions that Samsung’s new batteries will be produced in the Cheonan plant in Korea. It will also convert one of the lines in its Tianjin plant in China.