In recent years, and especially during 2025, we have begun to see how different mobile devices incorporate high-capacity batteries, to the point that previously unthinkable figures are beginning to become normal in certain models.
Much of this advancement has been made possible by the adoption of silicon-carbon batteries, a technology that until now has been driven primarily by Chinese manufacturers.
Samsung has advanced more cautiously in this area, but everything indicates that the South Korean company does not want to be left out of this trend during 2026.
According to a well-known leaker, the Samsung SDI division would be testing a dual 20,000 mAh battery intended for future phonesbased precisely on silicon-carbon technology.
The filtered design is especially striking, since the battery would be made up of two cells of different sizes. The main cell would have 12,000 mAh and a thickness of 6.3 mm, while the second would provide 8,000 mAh with an initial thickness of 4 mm.
Altogether, the system would reach a total figure of 20,000 mAh, far exceeding what is currently considered extreme in the mobile market.
In fact, the 12,000 mAh cell alone would already be above the 10,000 mAh batteries used in devices like the Honor Win series. According to this same source, the complete set could offer up to 27 hours of active screen and support around 960 charging cycles per year, at least on paper.
However, it is not all good news. During the tests, serious problems related to the longevity of the battery would have arisen. It is reported that the system showed signs of swellinga particularly worrying symptom for use on mobile devices.
Another source adds that the 8,000 mAh cell would have increased its thickness from the original 4 mm to 7.2 mm after the testsa considerable change that represents a clear alarm signal in terms of security and commercial viability.
In any case, it is only a leak, so all this information should be taken with caution. Even so, it is clear that Samsung does not intend to be left behind in the race to increase the battery capacity in the mobile phones that we will see in the coming months.