Lithium-ion batteries power every electric unicycle, and most problems start during charging. Past US recalls and warnings, how to charge safely, and what to check on a used wheel.
Every electric unicycle runs on a large lithium-ion battery pack. Built and cared for properly, these packs are reliable, but when they fail they can overheat and catch fire. Knowing the warning signs and charging habits that matter is the best protection.
Past US recalls and warnings
The Consumer Product Safety Commission has acted on electric unicycle batteries before. Two examples from 2022:
- July 12, 2022: the CPSC warned consumers to stop using the King Song KS-16S (serial numbers beginning “KS16S”) because its battery pack could overheat and catch fire. It reported one fire that caused smoke inhalation injuries to two people. The CPSC said King Song and retailer eWheels had not agreed to a recall.
- December 1, 2022: eWheels recalled about 500 Gotway and Begode unicycles (MSuper Pro, Nikola+ and RS models) because their batteries could ignite, after 14 reported fire incidents. Owners were offered a free replacement battery pack.
These notices covered specific older models. If you own or are buying a used wheel, search the CPSC recalls database for the brand and model.
How to charge an EUC safely
- Use the original charger, or one approved by the manufacturer for your wheel’s voltage.
- Charge where you can see it, on a hard, non-flammable floor, away from doors and escape routes. Do not charge while you sleep.
- Charge outside the home where you can. New York City’s fire department advises people to charge and store lithium-ion batteries and micromobility devices outside wherever possible.
- Let a cold wheel warm up to room temperature before charging after a winter ride.
- Unplug when charged. Most wheels stop charging automatically, but there is no benefit in leaving them connected for days.
Warning signs to stop and get help
- A swollen or bulging shell, a chemical or burning smell, or hissing or popping sounds.
- The wheel getting unusually hot while charging or parked.
- Damage after a hard crash or impact, or water getting inside the shell.
If you notice any of these, stop using and charging the wheel, move it away from anything flammable if it is safe to do so, and contact the seller or manufacturer. Never put a lithium-ion battery in household trash; take it to a battery recycling or hazardous waste site.
What to check on a used wheel
Battery health tells you how much of the original capacity is left, and it is the single most important number on a pre-owned EUC. Every used electric unicycle we list shows its battery health, condition grade and mileage.
Looking ahead, the CPSC has proposed making UL 2272 battery and electrical safety mandatory for electric unicycles. Read our summary of the proposed CPSC battery rule.
Sources
Feature photo: Unsplash.
