Samsung Uncertain on Galaxy S26 Ultra Battery Capacity; No Shift to Silicon-Carbon Technology or 65W Fast Charging

As Samsung gears up for the launch of the Galaxy S26 Ultra, challenges related to internal space limitations are anticipated. To effectively accommodate the S Pen, it is likely that the company may lean towards integrating silicon-carbon battery technology. However, recent rumors suggest that the battery size may remain consistent with previous models, including the Galaxy S25 Ultra, which features a 5, 000mAh battery. Additionally, there are concerns regarding fast-charging capabilities, with speculations indicating that Samsung may restrict the charging wattage to 45W.

Rumored Battery Specifications for the Galaxy S26 Ultra

The potential battery capacity for the Galaxy S26 Ultra is reportedly just under 5, 400mAh. However, it appears that the consumer version may still ship with the standard 5, 000mAh battery. Although there were earlier indications that both Apple and Samsung were considering the introduction of silicon-carbon technology in their upcoming devices, Samsung seems to be taking a cautious approach regarding its implementation in high-end smartphones.

According to recent updates from the tech insider @PandaFlashPro on X, disappointing developments have emerged regarding the Galaxy S26 Ultra. Notably, the anticipated increase in battery capacity has not materialized, and the expected 65W fast charging does not appear to be on the horizon either.

Samsung’s Charging Strategy: A Closer Look

In a related note, Samsung’s Galaxy G Fold—the company’s pioneering tri-fold smartphone—was recently listed in the 3C certification database. It is designed with charging capabilities capped at 25W, which may signal that Samsung is hesitant to push charging speeds much higher. Whether this strategy is a precautionary measure to prevent incidents similar to the Galaxy Note 7 or a deliberate choice to enhance battery longevity is still uncertain.

Battery Capacity is not Final yet but Under 5400mAh “if”they Increase, Charging Speed not 65w, 120Hz Refresh Rate, No Under Display Camera.

— PandaFlash 𝕏 (@PandaFlashPro) June 8, 2025

One key takeaway is that Samsung appears to be lagging behind its Chinese rivals in terms of both battery capacity and fast-charging technology. The Galaxy S25 Edge, for instance, did not utilize a silicon-carbon battery. A Samsung executive indicated that the flagship relies instead on advanced AI to optimize energy efficiency. While software advancements can enhance performance, there are physical limits dictated by the hardware itself that cannot be overlooked.

With the potential of silicon-carbon batteries, estimations suggested a substantial increase in the capacity of the Galaxy S26 Ultra to around 7, 000mAh, all while still accommodating the S Pen. Such a step would be beneficial for consumers; otherwise, Samsung might find itself struggling to justify the premium price tag of its flagship devices if they continue to lack cutting-edge features.

For ongoing updates, you can refer to this tweet from @PandaFlashPro.

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