Galaxy Z Fold battery specifications haven't changed in years, but Samsung finally turned the dusty page on that chapter at Unpacked 2026 in London. The new Galaxy Z Fold 8 Ultra brings long-awaited upgrades to both battery capacity and charging speed.In fact, Samsung says the Galaxy Z Fold 8 Ultra uses a silicon-carbon (Si-C) battery instead of a lithium-polymer (Li-Po) one. That's a first for the company, and it's something some fans have been waiting for a long time.However, the company was short on details and didn't reveal much about its Si-C battery implementation. It's likely a lithium-ion (Li-Ion) unit that uses a silicon anode (or partially silicon) for energy density gains.That sounds standard for Si-C batteries, but Samsung hasn't said how much of a density gain it has achieved over the Galaxy Z Fold 7's Li-Po unit.Even setting the Si-C technology aside though, other key battery specs have thankfully been upgraded this year. The Fold 8 Ultra battery is bigger and charges faster than any Fold before.The Fold series' first battery upgrade since the Fold 4Below is a brief history of the Galaxy Z Fold series' battery specifications and how things changed — or haven't — over the years since 2019.Li-Po 4,380mAh, 15W wired & 15W wireless charging: Galaxy Fold (2019).Li-Po 4,500mAh, 25W wired & 11W wireless charging: Galaxy Z Fold 2 (2020).Li-Po 4,400mAh, 25W wired & 11W wireless charging: Galaxy Z Fold 3 (2021).Li-Po 4,400mAh, 25W wired & 15W wireless charging: Galaxy Z Fold 4 (2022), Galaxy Z Fold 5 (2023), Galaxy Z Fold 6 (2024), and Galaxy Z Fold 7 (2025).The Galaxy Z Fold 8 Ultra features a Si-C (silicon-carbon) 5,000mAh battery with 45W wired and 25W wireless charging.Without a doubt, this is the most significant battery leap for the Galaxy Z Fold series since its debut in 2019. At least on paper. In practical terms, time will tell.We will get our hands on the Galaxy Z Fold 8 Ultra and talk more about battery improvement in our upcoming review. Samsung estimates the Galaxy Z Fold 8 Ultra can go from 0-67% battery charge in 30 minutes, and a full charge offers 27 hours of video playback.NOTE: Every Galaxy Fold uses a dual-battery design, with one battery larger than the other. Their individual capacities have changed slightly over the years, but Samsung — like the rest of the foldable phone industry — reports their combined capacity. For the Galaxy Z Fold 8 Ultra, that's 5,000mAh combined. Order the Galaxy Z Fold 8 Ultra today Samsung Shop https://www.youtube.com/watch?v=95urfzWqLq0