Description
To meet the specific demands of various applications in terms of cost and performance, and according to the expertise of manufacturers, multiple variants of Li-ion batteries have been developed and marketed. These variants differ in the nature of the electrolyte, the chemistry of the electrodes (anode or cathode), the type of separator used, and the format of the cells produced (pouch, cylindrical, prismatic). Each of these variations influences the behavior of the cells in abusive situations, and consequently, the safety of the systems that integrate them.
Among the available cathode chemistries, three families dominate the market: NMC (Nickel, Manganese, Cobalt) with its sub-variants depending on the proportions of lithiated metal oxides, LFP (Lithium, Iron, Phosphate), and NCA (Nickel, Cobalt, Aluminum). Although LFP chemistry has a lower energy density compared to NMC and NCA, it offers the advantage of reduced production costs. Many manufacturers also highlight potential safety benefits.
This note examines LFP cathodes and the implications of this cathode chemistry on the risk profile of Li-ion battery cells and systems. After presenting accidentology elements, the reactivity and risks associated with LFP Li-ion batteries will be detailed and compared to other cathode chemistries. Finally, the parameters that can influence the reaction of these batteries will be discussed.
