Japan's authorities get proactive amid surge of exploding portable power banks

As portable power banks have surged in popularity all over the world, they pose a substantial fire hazard, as is best illustrated in a string of accidents that have plagued Japan.

The island is facing a growing safety crisis linked to portable power banks, as the number of fires and related accidents has surged sharply in recent years.

The issue has placed pressure on authorities to strengthen regulations and improve public awareness of the dangers associated with lithium-ion batteries.

A major incident in Tokyo on September 25 highlighted the problem, when a power bank connected to a smartphone allegedly sparked an apartment fire, leaving six people hospitalized with smoke inhalation. There were 123 similar incidents in 2024, more than double the 47 cases recorded in 2020, according to an article by Nikkei Asia on this rising issue, which reports that most of these incidents occurred while power banks were being used to recharge smartphones.

Power banks rely on lithium-ion batteries, which use a flammable organic solvent as an electrolyte. If a short circuit occurs, the battery can rapidly overheat, causing the solvent to ignite. Despite existing safety measures, including Japan’s national product safety standards introduced in 2019 that require all power banks to carry a “PSE mark”, defective or poor-quality devices remain a hazard. Even compliant products have occasionally required recalls — yet these recalls have often proven ineffective.

A particularly troubling example occurred in July 2024, when a fire broke out on a Tokyo train due to a Chinese-made power bank that had already been recalled in June 2023. Under Japanese law, manufacturers are required to make reasonable efforts to recall defective goods. However, the Consumer Affairs Agency reported that only 12% of the affected products had been recovered by July 24, reflecting weak recall enforcement and low consumer awareness.

According to the article, the problem is exacerbated by the rise of cross-border e-commerce, which allows foreign sellers to ship products directly to Japanese consumers. Many of these imported power banks are inexpensive Chinese-made devices lacking the PSE mark, placing them outside Japan’s regulatory oversight. As a result, such products are rarely subject to recalls, even when found to be defective or dangerous.

The issue extends beyond consumer safety to waste management, with discarded lithium-ion batteries causing fires in garbage trucks and incinerators. In fiscal 2023 alone, Japan recorded about 21,000 incidents of smoke or fire from lithium-ion batteries improperly disposed of with regular waste.

One major obstacle is that power banks and many other modern electronics now have non-removable batteries, making it difficult to separate them for safe disposal. The Ministry of Internal Affairs and Communications estimates that over 500 metric tons of lithium-ion batteries are mixed with ordinary garbage each year.

To address these concerns, the government plans to revise recycling regulations. Starting in April 2026, mobile batteries, smartphones, and heated tobacco devices will be added to the list of items that manufacturers, importers, and retailers must collect and recycle. The revised legislation introduces penalties for noncompliance, but enforcement against overseas businesses remains uncertain.

Experts stress that improving consumer awareness is as important as regulatory reform. “While many mobile batteries are equipped with high-level safety measures, it depends on the manufacturer,” said Chiharu Tokoro, a professor at Waseda University’s Faculty of Science and Engineering. “The key is to steadily inform consumers of the risks,” Tokoro added.

By Nazrin Sadigova