Overview of battery fire risks, flame retardant solutions and technology perspectives. 60 pages. 125 references. Current lithium-ion batteries stock up to 250 Wh/kg of energy, but this could in theory increase to 3 500 Wh/kg, so increasing fire and explosion risks. Most lithium-ion batteries use polymer separators (e.g. polyethylene, polypropylene) and organic solvent electrolytes or solid polymer-based electrolytes, all of which are flammable. The review indicates that phosphorus-based FRs, either additive or reacted into polymers, can reduce fire risks of electrolytes, including in combination with inorganics (e.g. aluminium, boron). Phosphorus FRs are also effective in reducing flammability of separators, including in combination with nitrogen, sulphur, silicon and/or metal oxides. Fire safety of battery cell and pack enclosures, cables and other parts can also be ensured by appropriate use of PIN FRS.
“Recent progress in flame retardant technology of battery: A review”, W. Liu et al., Chemicals and Materials (2022), https://doi.org/10.1016/j.recm.2022.07.005