Samsung's Galaxy S27 Ultra might receive its first substantial battery upgrade in several years, according to recent information. The device is under evaluation with a larger battery than initially planned, potentially offering an edge over the expected iPhone 18 Pro Max in capacity. The latest details also indicate the company may stick with lithium-ion technology instead of switching to silicon-carbon batteries, even as some competing brands make that change.

Samsung Reportedly Testing Bigger Batteries for Galaxy S27 Ultra

Reports suggest Samsung is assessing 5,600mAh and 5,800mAh battery cells from Samsung SDI for the Galaxy S27 Ultra. Earlier plans had settled on a 5,200mAh lithium-ion cell, but evaluation of larger options has resumed. Successful testing could lead to a final capacity above 5,500mAh.

The information shows Samsung continuing with standard lithium-ion batteries rather than adopting silicon-carbon cells for the flagship. Several Chinese manufacturers have shifted to silicon-carbon options for their higher energy density. Samsung is instead focusing on improving the efficiency of its existing lithium-ion approach.

Should the upgrade occur, it would represent the first battery capacity increase for the Ultra series in years. Previous models from the Galaxy S20 Ultra through the Galaxy S26 Ultra all used 5,000mAh cells. Endurance gains came from refinements in hardware and software rather than larger listed capacity.

Recent reports indicate the iPhone 18 Pro Max may feature a 5,425mAh battery in its eSIM version and 5,235mAh in models with a physical SIM tray. If accurate, the Samsung device would hold the higher capacity of the two.

Battery size alone does not determine real-world performance. Different hardware and software between the brands mean actual endurance requires testing after release. The specifications remain unconfirmed until an official announcement.