Smart rings present a unique challenge to manufacturers wanting to keep the design slim and wearable, while also including more advanced features, yet still including a battery that provides days of use on a single charge.
Battery technology company Grepow has announced a new type of battery designed specifically to address this complicated task, and it has the potential to change the next generation of smart rings.
New design
Grepow’s new battery uses a silicon-carbon anode, just like we’re seeing in new smartphones, which has the benefit of increasing battery capacity and energy density without dramatically increasing physical size. It’s ideal for small wearables.
This differs from the lithium-polymer (LiPo) battery used in the Oura Ring and the Samsung Galaxy Ring. Grepow states its new battery will have a 30% higher capacity without increasing volume compared to existing batteries.
The anode isn’t the only advancement, but we’ll have to get a bit technical to explain it. In a white paper on its new battery tech, Grepow explains how most smart ring batteries are made using a “winding” process, where materials are layered and then wound into a suitable shape.
For its silicon-carbon battery, Grepow uses a process called “E-stacking,” where layers are stacked, then heated into a uniform arc shape.
The company claims the resulting uniform structure reduces mechanical stress, increases performance, and extends the lifespan to around 500 recharge cycles. The average for a LiPo battery seems to be between 300 and 500 cycles.
Thinner, safer batteries
Elsewhere in the white paper, Grepow reveals it can produce micro-batteries measuring just 1mm thick and only 4.1mm wide, which is assisted through the use of special tabs to connect cells together.
The E-stacking process, use of silicon-carbon anodes, the special tabs, and uniform structure increases battery safety by 80%, according to Grepow’s white paper. This is particularly notable given a recent story about a Galaxy Ring’s battery expanding while the ring was being worn.
Other advantages of the new battery type include lower performance temperatures allowing a smart ring to properly function in more varied environments, and more stable power delivery for intensive features like GPS and continuous heart rate tracking.
Grepow also says it’s working on fast charging technology for the battery, where a five minute charge will return a day’s worth of use.
When will we get one of these batteries?
Grepow sums up the advantages of its E-stacking battery like this:
By removing long-standing constraints in small-form-factor battery design, Grepow’s patented technology enables thinner, lighter, and longer-lasting smart rings, paving the way for seamless 24/7 health monitoring, gesture control, and biometric sensing in everyday wear.
Unfortunately, the company doesn’t indicate when a smart ring with its battery technology inside will arrive, or when the battery will be available for manufacturers to test. Android Police has contacted Grepow for comment and will update when we hear back.
The Grepow E-stacking silicon-anode battery joins rumors Samsung may use a solid-state battery for the Galaxy Ring 2.


