Details of the Samsung Galaxy Watch Ultra 2 and Galaxy Watch 9 wearables, likely to be announced at Samsung’s Unpacked event this week, have surfaced.

Leak publisher account evleaks, once manned by now-retired leaker Evan Blass, has posted promotional materials for the Galaxy Watch 9 and Ultra 2 that give away some of the upcoming wearables’ core specs.

The battery capacity of the Samsung Galaxy Watch Ultra 2 is the most interesting of them all. At 800mAh, the cell is 1.35x the capacity of original 2024 Galaxy Watch Ultra 590mAh battery.

Considering the new watch is apparently not only no thicker than the old one but 12 per cent thinner, this suggests Samsung has used a higher-capacity battery technology, most likely silicon-carbon.

This is used fairly widely in phones from Chinese manufacturers like Oppo and Xiaomi, but Samsung does not use silicon-carbon in its phones currently.

The Samsung Galaxy S26 Ultra instead has a more conventional lithium ion battery with a graphite anode instead of the newer silicon-carbon type. While both generations are still effectively lithium ion batteries, the upgrade is consistent with the boost in capacity seen in these Samsung Galaxy Watch Ultra 2 specs.

Why doesn’t Samsung use silicon-carbon designs already? One theory is a pro-consumer one, that Samsung is cautious to use the newer design as its early iterations may have significantly lower charge cycle lifespans.

Honor was among the very first to adopt the silicon-carbon battery technology in phones, in the Chinese version of the Honor Magic 5 Pro from 2023. Only now is the time approaching when the first waves of silicon-carbon batteries in mainstream gadgets are stress-tested in real-world conditions towards what might be more advanced stages of battery degradation.

Three years on, though, it appears Samsung finally has some confidence in the tech. The leak suggests the battery life claim for the Galaxy Watch Ultra 2 has jumped from 48 hours to 60 hours — a little under the 1.35x capacity jump.

Samsung Galaxy Watch Ultra 2 Specs

The watch screen also appears to be able to hit 5,000-nit brightness, where the 2024 Ultra peaks at 3,000 nits. It’s an impressive leap, but not one that will radically alter anyone’s real-world experience, when the first Ultra watch was already plenty bright.

Other core specs include a part titanium casing, a Snapdragon Wear Elite processor and IP69K water resistance, although it’s actually likely to have a higher water resistance spec of at least 10ATM too.

A few specs for the standard Samsung Galaxy Watch 9 have emerged as well, although these are mostly more familiar. It’s rumored to come in two sizes, 40mm and 44mm, with 390mAh and 445mAh batteries respectively.

These more affordable watch lines also reportedly get the bump up to a Snapdragon Wear Elite processor, from the Exynos W1000 used in the current generation. You can expect to hear more about the Samsung Galaxy Watch Ultra 2 at Samsung Unpacked, held on July 22.