Despite standing out for its super-slim design, the Galaxy S25 Edge failed to click with consumers. Multiple reports indicate the phone’s not selling well, possibly due to its sub-par battery life, forcing the company to cut back on production. Yet, Samsung supposedly wants to replace the Galaxy S26+ with an S26 Edge next year. And if a new leak is to be believed, the company may address the biggest limitation with its current Edge phone the second time around.

The Galaxy S25 Edge is Samsung’s slimmest Galaxy phone yet, featuring a 5.8-inch thick waistline. But this thinness comes at a cost, with the phone packing a paltry 3,900mAh battery. That’s not enough to provide juice to the 6.7-inch AMOLED display and the power-hungry Snapdragon 8 Elite chip for the entire day. Worse, the relatively slow 25W charging speeds don’t help either.

Despite the battery life shortcoming, a Samsung executive praised the S25 Edge as being the “Goldilocks” of smartphones. Sadly, that has not translated into sales, with consumers likely ditching the device due to its poor battery life.

Leaker Ice Universe claims the Galaxy S26 Edge will feature an even thinner design than the current model. And yet, it will pack a larger battery “thanks to new battery material technology.”

Silicon-carbon might solve the Galaxy S26 Edge’s battery woes

While not mentioned, Samsung may adopt the silicon-carbon battery technology inside the S26 Edge next year. That should allow it to boost the battery capacity beyond 4,000mAh. Coupled with the use of other power-efficient components, Samsung could ensure the S26 Edge lasts longer than its predecessor despite sporting an even slimmer frame.

It’s unclear if the company will adopt the same battery technology on its other flagship devices for next year.

Chinese smartphone makers are already using silicon-carbon batteries to pack denser cells into their phones, with capacities surpassing 7,000mAh on their mid-range devices. For example, while the 4.2mm-thick Galaxy Z Fold 7 packs a 4,400mAh battery, the Oppo Find N5, which measures 4.21mm when unfolded, packs a significantly larger 5,600mAh cell.

Even the OnePlus 13, which measures almost the same as its predecessor, packs a substantially beefier 6,000mAh cell — 1,000mAh more than Samsung’s Ultra flagship, the Galaxy S25 Ultra.