China is introducing new regulatory standards for electric car batteries that will represent some of the strictest safety and testing requirements in the world. Set to take effect on July 1, 2026, the “Safety Requirements for Power Batteries of Electric Vehicles” will essentially prohibit fires and explosions even after thermal propagation, or the spread of an uncontrolled temperature increase from one battery cell to another.
Electric car fires are already rare, and some critics contend that China’s new rules demanding no fires or explosions are unrealistic. Whereas in the past, China had mandated that vehicles warn passengers five minutes before a potential fire or explosion event, they simply cannot happen under the new rules. That could raise the cost of vehicles from smaller brands if they struggle to develop battery technology that can meet the standard.
But one of the leading battery makers in China, CATL, claims it already introduced a battery technology in 2020, dubbed simply “No Thermal Propagation (NP),” that meets the standards. “The new standard will effectively reduce the risk of power battery fires after collisions in new energy vehicles, better protecting consumers’ lives,” the company told CarNewsChina. CATL is a major supplier of batteries to Tesla’s Shanghai plant (Tesla’s in-house battery, the 4680, has been criticized for not living up to expectations).
The new regulatory requirements come with some tests for manufacturers to follow:
- Bottom impact testing to evaluate battery protection capabilities when the underside experiences a collision
- Fast-charging cycle safety testing requires batteries to withstand 300 fast-charging cycles without fire or explosion during subsequent short-circuit tests
Increased safety regulations in the EV space are inevitable, and the new ones out of China come just after the country announced new testing requirements for autonomous driving systems. The announcement followed a deadly crash in a Xiaomi SU7 that was operating in a driver assistance mode shortly before hitting a concrete barrier. Automakers in China are no longer allowed to use terms such as “autonomous” or “smart driving” in their marketing materials.
Some might have expected China to implement a more gradual extension of its thermal runway requirement, perhaps by mandating new alerts 10 or 15 minutes before a catastrophic failure. One unintended consequence could be a manageable fire incident turning into a big explosion type scenario if there is a fault in one cell with no thermal propagation.
Studies have found that EVs are no more likely to catch fire than traditional combustion vehicles, and newer battery packs use technology like thermal sensors to detect overheating as well as liquid nitrogen to keep nearby cells cool. But when they do catch fire, particularly following a crash, electric car batteries undergo a thermal runaway event in which the temperatures continue to uncontrollably get hotter and hotter, and require immense amounts of water for firefighters to extinguish. Discussions on Reddit show firefighters commiserating on how to put out such fires.
China has quickly taken a lead in the EV space, with brands like BYD and Xiaomi releasing cars at rock-bottom prices and with features that compete with Tesla, like self-driving systems and batteries that can charge in record times. Some critics contend that the country unfairly subsidizes its industries with cheap materials like rare earth metals, but companies like BYD have managed to expand globally and are making the cars profitably. China is an open market, just perhaps in a different form than what the Western world is accustomed to. The historical trend is for China to champion national brands and that one is now BYD. Another small benefit of a one-party dictatorship is that once it decides to prioritize a sector like EVs, it goes all in, and that is why the country has managed to leapfrog players like Tesla.
