On September 25th, a fire broke out in an apartment building in Tokyo’s Suginami Ward, injuring six people after a mobile battery used for charging a smartphone reportedly ignited. According to the Tokyo Fire Department, the blaze began when the resident left her phone charging overnight. Over 20 square meters of the apartment were burned, and nearly 30 fire engines were dispatched before the flames were put out. Fortunately, all injuries were minor, but the case is one of many lithium-ion battery–related fires reported across Tokyo this year.
These incidents are not isolated. In the first half of 2025 alone, the Tokyo Fire Department recorded 143 fires caused by products using lithium-ion batteries, with mobile chargers and smartphones being the top culprits. Fires have also occurred on trains, such as the Yamanote Line and Joetsu Shinkansen, when passengers’ mobile batteries suddenly overheated or emitted smoke. Many of these cases involved older or damaged batteries or the use of non-certified chargers, making the risks relevant to anyone who carries portable devices.
For the Saint Mary’s International School community, this serves as a clear warning. Students often carry mobile batteries in their backpacks for long school days, sports practices, or commutes, which increases the chances of overheating or accidental damage. To stay safe, students and families should use only manufacturer-approved chargers, avoid overcharging devices overnight, and replace aging batteries. As portable devices continue to play a central role in student life, taking simple precautions can prevent dangerous accidents.
