The battery difference in battery between the Galaxy S25 with its 4,000 mAh battery and the Xiaomi 15 with its 5,240 mAh battery is already very important. This gap should still be widening in 2026, at least if we believe a post https://www.weibo.com/604856942/pft4J0HFz?page=Profilefeed from the Chinese Leaker Digital Chat Station, in which it reports the first certification of the Galaxy S26 in China.
Consequently, the Samsung model bearing the SM-S9420 number and with a 6.27-inch screen will offer a 4,300 mAh battery (4,175 mAh nets), 300 mAh more than the current Galaxy S25. An improvement certainly, but which remains quite low compared to certain Chinese brands. The first 6.3 -inch compact cameras with a 7,000 mAh battery should arrive on the market this fall, including the Xiaomi 16ain that Vivo and Oppo devices.
The Xiaomi 16 Pro Max, larger, the Vivo X300 Pro and the Oppo Find X9 Pro with their 6.7 to 6.9 -inch screens, should have even higher capacities, so that Samsung seems relatively conservative in its planning upgrades. On the other hand, the Galaxy S26 Ultra should also benefit from a rapid recharging of 60 watts, against 45 watts currently, which was recently confirmed in a first update of the one UI 8 firmware.