Samsung’s upcoming Galaxy Z Fold7 could be the slimmest foldable phone ever, with a jaw-dropping 3.9mm thickness when unfolded and near-invisible 1mm bezels around its larger screen, according to leaks from trusted tipster Ice Universe. But the phone’s rumored 4,400mAh battery has sparked concerns about stamina.

　The Z Fold7’s unfolded dimensions are said to measure 158.4mm x 143.1mm x 3.9mm, up from last year’s Z Fold6 (153.5mm x 132.6mm x 5.6mm). The ultra-thin bezels would boost the screen-to-body ratio, offering a more immersive display.

　While Samsung claims "new battery and charging tech" will offset the larger screen’s power demands, critics argue the unchanged 4,400mAh capacity—smaller than rivals like Google’s Pixel Fold—may struggle with daily use. “Bigger screens drain batteries faster,” noted one analyst. “This could be a dealbreaker.”

　The Z Fold7’s design leap follows years of refining foldables, but balancing portability and endurance remains a hurdle. If leaks hold, Samsung will unveil the device this summer.