Origins of safety concerns SCIENCE ADVANCES REVIEW MATERIALS SCIENCE Materials for lithium-ion battery safety Kai Liu',Yayuan Liu',Dingchang Lin',Allen Pei,Yi Cui2* Samsung Note 7 after the battery The Fire Triangle in a caught fire Li-ion battery O2:To sustain the fire Temperature/heat: Gas release from side Reaching the ignition reactions during charge/discharge OXYGEN point of the fuel IGNITION Thermal runaway due to heat released from side reactions FUEL Fuel:The thing to catch fire The organic liquid electrolyte is combustible 5Origins of safety concerns Fuel: The thing to catch fire The organic liquid electrolyte is combustible O2: To sustain the fire Gas release from side reactions during charge/discharge Temperature/heat: Reaching the ignition point of the fuel Thermal runaway due to heat released from side reactions The Fire Triangle in a Li-ion battery Samsung Note 7 after the battery caught fire 5