At Vvolt, we care about advancing the cause of electric micromobility, so it’s important for us ensure that our e-assist systems are safe, from batteries to chargers to motors and control systems. Our battery packs pass UN 38.3 safety testing and our chargers are UL-listed, and have additional features designed to ensure the utmost safety for riders and the charging environment.
While Stellar Series batteries are designed and built to pass EN and UL standards– at the moment they are not UL certified. We are moving to obtain UL certifications on future productions.
Learn how we’ve taken steps to ensure safety in your Vvolt battery system.
- Quality factories - We’ve vetted our partner factories to ensure their sourcing and process control are top-notch.
- Quality cells - we only use "name brand" cells. At the moment that brand is LG, though Samsung and others also have reliable products.
- Sealed pack construction - Our battery packs are sealed against water intrusion and have an IP65 waterproof rating, as does the rest of the electrical system in our ebikes.
- Quality BMS systems – it costs more but it’s important to use well-made onboard battery management chips and temperature sensors like we do.
- Single Cycle UL-Listed Chargers - Our chargers automatically shut down when the charge cycle is complete, so they don't "float" charge and continuously top off a battery when left on the charger. This reduces heat and chance of overcharging, as well as prolonging battery life.
- Lower charging amps - our batteries can take 4 amps of charging current but we spec a slower 2 amp charger as it generates less heat.
With ebike safety in the news, we thought this is a good place to address some of the common causes of battery failures and fires:
- Cheap battery packs on cheap ebikes are being run hard by commercial (delivery) riders. These folks are constantly cycling their batteries quickly, often charging with high amperage chargers to get a fast charge. This runs up more heat in the pack and charger and risks fire.
- Rebuilt batteries- this is another one very common in NYC fire reports. Basically, folks are getting dangerous cheap rebuilds of worn packs, maybe not even replacing all cells which can result in dangerous imbalance and heat buildup, esp. if used with higher-amp fast chargers.
- Chargers that "float.” When Li-Ion batteries charge they run up to the "saturation" point, and then drop off a little voltage as the energy storage stabilizes. When used with a safe single-cycle charger like ours, this can result in a "full" charge where the battery only gets to 95% once it settles (and that’s OK!) Some chargers will then cycle back on when detecting less than 100% charge, and this cycling can cause heat buildup. This is particularly problematic in older batteries that have developed more internal resistance due to natural "plating" of metallic Lithium over time.
- Overloaded circuits and surge protectors – another common image associated with news reports is of rooms full of charging batteries. Make sure your household circuits and surge protectors are built to handle the load with any appliance! A single 2-4 amp charger is usually not a problem, but stringing together 8 chargers could overload a common 15 amp circuit.
- There was a recall of high-end eMTB batteries last year, it turned out they were shorting because riders were washing their bikes with high-pressure hoses, forcing water into the charging port where corrosion built up and eventually caused a short and a couple instances of smoking/fire. For this reason we recommend using a washcloth and mildly soapy water to wash your ebike, not a hose!
All of the above are related to low-cost packs, unrated chargers, risky charging or other careless behavior. Note when you see reports of fire that it's extraordinarily rare for the report to mention high-quality ebike brands. Sometimes a closer read will uncover the fact that reporting agencies (Police, Fire, etc) use the term "ebike" even when it's not what we’d call an electric bike, but in fact an unlicensed electric motorcycle.
In summary: If you're responsible in using the stock Vvolt battery and charger then your risk of battery fire is extraordinarily low.