Samsung Galaxy S27 Ultra and S27 Pro batteries pictured in a new certification

According to the latest documentation uncovered in the database, the newly spotted batteries bear the official manufacturer model numbers EB-BS957CBY and EB-BS958DBY. These specific designations align seamlessly with the previously identified internal tracking codes for the upcoming flagship generation, corresponding directly to the SM-S957 model designation for the Galaxy S27 Pro and the SM-S958 model designation for the Galaxy S27 Ultra. Furthermore, the regulatory filings confirm that the manufacturing responsibilities for these critical components have been entrusted to Zhuhai CosMX Power, a prominent battery supplier based in China that frequently collaborates with major consumer electronics brands.

While the newly published photographs from the Safety Korea platform provide visual confirmation of the battery units sitting side-by-side during the compliance testing phase, the exact printed capacity figures are unfortunately obscured and illegible within the compressed image files. However, this minor visual hurdle hardly leaves industry observers in the dark, as the precise energy metrics for both the Pro and Ultra variants have already leaked through separate regulatory channels over the past few months.

The underlying technical specifications first began circulating across supply chain leaks back in July, establishing a baseline of expectations for how much power Samsung’s next top-tier devices would pack. Those initial leaks were subsequently reinforced when the components traveled through China’s mandatory 3C certification process in September. Through those successive regulatory filings, it became clear that the Galaxy S27 Ultra will feature a battery carrying a rated capacity of 5,534 mAh. In everyday consumer marketing terms, this rated minimum is expected to translate into a typical advertised capacity of approximately 5,700 mAh.

Similarly, the slightly more streamlined Galaxy S27 Pro will feature a battery sporting a rated capacity of 5,087 mAh, which is widely projected to equate to a typical market capacity of 5,200 mAh. Alongside these notable upward adjustments in energy storage, the documentation indicates that both flagship models will maintain support for 60W wired fast charging. This charging threshold matches the capabilities found on the current-generation Galaxy S26 Ultra, signaling that Samsung is prioritizing sustained thermal management and battery longevity over a race for higher raw wattage numbers.

To understand the significance of these upcoming figures, one must look at how Samsung has handled flagship power capacities in recent years. For multiple generations, the South Korean technology giant maintained a firm ceiling on its premier Ultra models, keeping the typical battery capacity anchored at a static 5,000 mAh. If the anticipated typical figures for the upcoming generation prove to be accurate, the Galaxy S27 Ultra will represent a substantial generational leap forward. The new Ultra cell will provide roughly 700 mAh—or a notable 14 percent—more capacity than the 5,000 mAh cell found inside the preceding Galaxy S26 Ultra. Even the smaller Galaxy S27 Pro manages to edge past that historical baseline, offering an extra 200 mAh, or a 4 percent increase, over the older Ultra standard despite its more compact footprint.

Reaching this milestone was apparently no simple task for Samsung’s hardware engineering teams. Industry reports surrounding the development of the S27 series revealed that Samsung seriously evaluated even more dramatic capacity increases, including testing an aggressive 7,000 mAh prototype during the early conceptual phases. However, engineers ultimately decided against moving forward with the massive 7,000 mAh cell. The primary deciding factor in abandoning the ultra-large prototype was the physical constraint of the device’s internal chassis, specifically the need to preserve adequate space for the integrated S Pen stylus silo without significantly increasing the overall thickness or weight of the smartphone. By settling on the refined 5,700 mAh typical cell, Samsung managed to secure a meaningful boost in battery endurance while retaining the signature productivity features that define the Ultra product line.

Despite the steady stream of regulatory filings, battery sightings, and CAD render leaks, questions remain regarding the precise commercial rollout schedule for the Galaxy S27 family. Samsung has not yet officially announced a launch date for the upcoming flagship devices. While industry watchers have speculated on potential schedule shifts driven by global component supply dynamics and rising memory costs, a recent market report suggests that Samsung may ultimately decide to return to its traditional early-year launch window, pointing toward an official unveiling in January or February. As these devices continue clearing safety databases and regulatory hurdles across international markets, a definitive announcement from the manufacturer is expected in the coming months.