SaferProducts incident

Failure type

Fire / ignition

Incident narrative

SaferProducts.gov consumer incident report 20260323-A4320-2147322367. Severity: Incident, No Injury. Product: Ultrahuman Ultrahuman Ring AIR (Ultrahuman smart ring wearable health tracker. Color: Matte Grey, Size: Size 8. The device consists of a titanium outer shell, a resin inner shell housing sensors and a lithium-ion battery, and a proprietary charging dock.). Incident: I am reporting a severe battery failure and fire hazard involving a wearable health tracker called the Ultrahuman Ring. Over my warranty period, I experienced constant hardware failures, requiring five separate replacement rings. Recently, while attempting to charge one of the defective rings on its proprietary charging dock, the device became pretty hot to the touch. The internal lithium-ion battery rapidly expanded, causing massive physical bumps to form on the ring's casing. The swelling was so severe that the ring became physically stuck to the charger. The product was being used exactly as intended for charging. Fortunately, no injuries occurred because I noticed the extreme heat and disconnected it before it could catch fire or explode, but the device poses a severe thermal runaway risk. I had previously contacted their support about another ring not connecting, but the issue with the battery on the previous ring did not happen yet, so Ultrahuman was not contacted about the expanding battery.