Electrical applications in Internet of things and e-vehicles: Passive fire safety needs and solutions

The exponential growth of electrical devices in Internet of things and e-vehicles will lead to new fire safety challenges. As electric fires rank second among all fires and electrical equipment recalls show safety gaps, fire safety requirements must be better enforced and improved. The analysis of the current qualitative pass/fail requirements for electrotechnical products shows that they provide a basic level of fire safety. Fire testing of car and bus interiors, mandatory worldwide, is too low level. Alternative tests, such as the microscale combustion calorimeter, are discussed. Buses have to comply with additional fire tests. E-vehicles must meet a fire exposure test for electric powertrain and specifications to prevent thermal runaway of batteries. Charging stations must comply with fire and overheating requirements for enclosures, plugs, and sockets. Passive fire safety needs are primarily met by using flame retardants, and for preventing thermal runaway of batteries, by intumescent coatings, interlayers, and ceramifying products.