eBikes Face Safety Hurdles

From dodgy batteries to scary stories in the media, the bicycle industry faces technical and regulatory challenges.

By Scott Mace

The bicycle industry is undergoing a renaissance and inflection point, spurred on by innovations in electric bicycles, or ebikes. But the industry faces safety questions that threaten to short-circuit the growth of ebikes.

At the CABDA West show in early January 2023, an expert engineer briefed bicycle dealers and shop owners about these safety questions, and challenged them to get more involved as controversies swirl.

In a short time, evolution of ebikes has come a long way, thanks to innovative technology. Mid-drive propulsion systems, quiet and efficient hub motors, and multi-speed or infinitely variable transmissions make these new ebikes peppier and more fun to ride than predecessors dating all the way back to their first incarnations in the 1890s.

Older lead-acid batteries have given way to newer lithium-ion batteries already in use in electric cars, computers, and other consumer electronics. But lithium-ion battery packs contain a tremendous amount of energy, and that can be risky, said engineer Mike Fritz, chief technology officer at Human Powered Solutions, which provides consulting services to ebike manufacturers and governments.

Lately, these risks have grabbed headlines. At least 19 people died in the United States in 2022 because of fires or overheating incidents related to battery-powered products such as ebikes, scooters, and hoverboard, according to the U.S. Consumer Product Safety Commission (CPSC).

The New York Fire Department blames at least 208 fires in 2022 on these devices, resulting in 142 injuries and six deaths.

Fritz estimates that between 60,000 and 85,000 delivery riders of these devices, as well as traditional bicycles, operate in New York City alone. “These are not well-paying jobs,” Fritz said. “These guys can’t afford to buy a $3,000 ebike at retail, so they buy a cheap imported bike from questionable sources, equipped with batteries that are not up to the task.”

These operators subject these devices to usage which is “very stressful to the battery pack,” using “substandard battery cells that are prone to failure, being used for 10 to 12 hours a day, being recharged by potentially incompatible battery chargers, and oftentimes charged overnight in a rider’s apartment. It’s a very serious problem.”

While these cheaply-made ebikes don’t directly affect dealers of ebikes sold in traditional bike shops, the media is failing to distinguish between well-designed ebikes/battery systems, and/or well-maintained and utilized charging systems, and poorly-designed or mismatched tech that is overwhelmingly responsible for these fires, according to Fritz.

“The news media doesn’t differentiate,” Fritz said. “It’s all ebikes.”

Fritz is no newcomer to ebike engineering. In 1997, Lee Iacocca recruited him to help develop electric bikes for his EV Global Motors company, one of the first ebike startups in the United States.

Whatever the quality of the batteries involved, lithium-ion fires are significantly different from the conventional kind of structure fire that most fire departments are used to dealing with. In battery packs with tightly-packed cells narrowly separated from each other, one runaway lithium-ion battery can quickly spread to all other batteries in the pack, and then adjacent packs. These fires are more difficult for fire departments to douse than conventional fires, and can quickly ignite structures.

“Customers are talking about the dangers of lithium-ion batteries when they’re shopping for an electric bike,” Fritz said. “I can guarantee it’s going to rise significantly in the near future, because the remedial action that’s been planned up until now I’m afraid is not going to be effective.”

The action proposed has already gotten off to a false start. In New York City, many delivery workers are independent contractors and have no choice but to charge the devices in their homes and apartments. The New York City Housing Authority considered banning electric bikes in its buildings, but backed down following backlash from workers who believe such a ban could deprive them of their livelihood.

While the NY city council continues to deliberate on solutions ranging from banning the sale of second-use batteries to funding education of riders, the CPSC is fast-tracking steps to seize imported lithium-ion batteries and ebikes that fail minimum industry standards. In a December 2022 statement, CPSC commissioner Richard Trumka pledged to crack down on these rogue technologies with the same “swift action” it took with hoverboards in the 2010s.

Since the risk of fires even in standard ebikes, batteries, and charging systems is never zero, Fritz called upon bike dealers to advise and train customers, and bike shop employees, in their proper care and maintenance. “I’m fond of drawing the analogy that the lithium-ion battery is a high-energy storage medium much like gasoline is,” he said. “You need to make sure your staff is trained and your shop is properly equipped.” Any kind of extreme temperature – sitting in hot sunlight, or outside in temperatures below 40 degrees Fahrenheit, could lead to battery failure, although some of the better chargers have temperature sensors to shut down charging in the case of such extreme temperatures.

Fritz wasn’t talking hypothetically about calamities in bike shops themselves. In the aftermath of Hurricane Ian in October 2022, a bike shop in Fort Myers that sold Pedego ebikes was “utterly destroyed” and its ebike and battery inventory ruined due to being immersed in salt water for a period of hours, he said.

Finally, another fiery risk revolves around the need to safely recycle batteries that may be damaged if they are dropped, or are simply at the end of their useful life.

Fritz’s firm is collaborating with the National Bicycle Dealers Association to develop and proliferate guidance for bike dealers, keeping in mind that if the industry cannot police itself, a flurry of new regulations and oversight from all levels of government are sure to follow – and may be inevitable no matter how well the industry can get its own act together.

Speaking directly to dealers at CABDA West, Fritz said “the chances you’re ever going to experience a battery failure are minuscule if you’re sourcing quality product and you’re properly treating and handling it. But it’s not zero, when you consider the billions of battery cells that are manufactured every year for all sorts of different applications. There is a defect rate in any manufacturing process.”

Underwriters Laboratories is also promoting its own related standards, one that applies to the batteries themselves, and another to the ebike’s electrical system. Fritz urged dealers to only buy UL-approved batteries and related systems. “We believe it’s a wise investment,” he said. “It’s cheap insurance to ensure that you’re not going to hurt anybody and your products aren’t going to aren’t going to fail catastrophically and affect your customers.”

Finally, the insurance industry is casting its own wary eyes over the surge in ebike safety concerns. Here, it’s not just the electrical components at issue. “There’s lots of news available talking about that the fact that because ebikes can go faster, and they’re mixing with pedestrians and slower conventional bicycle traffic, there’s injuries occurring,” Fritz says. There are even reports of bike shops being unable to obtain insurance due to their heightened liability if anything goes wrong inside or outside of their shops.

As 2023 unfolds, and sales and rentals of ebikes soar, these safety issues will impact law, regulation, and everyday usage. How the industry rises to the challenge will determine whether the trajectory of the product soars, or bellyflops as early hoverboards did in previous years, perhaps with much deadlier consequences this time.

Scott Mace is a journalist who has written about technology since the 1980s. He is currently writing a book about the history of bicycling advocacy. He is based in Carmel-by-the-Sea, California. His Twitter feeds are @scottmace and @scottmace2.

Copyright 2023 by Scott Mace