Smartphone users should beware of the cold temperatures that can have a deadly effect on smartphone batteries. The sub-zero temperatures can cause the the batteries to stop working.
Most phones today use lithium-ion batteries for power and inside each battery is a substance called liquid electrolytes. The ions flow through the electrolytes and deliver energy to the phone. The electrolytes become thicker and it slows down how fast the ions can travel through it. The battery can't produce enough power to keep the phone going and it dies.
Once the chemicals warm up, the phone will start working. You can help protect your phone by keeping the battery fully charged, use a case and don’t leave your phone in a cold place for a long time. Especially in the car overnight!
Bundle up those smartphones!