https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=10174620Ther...

https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=10174620

There are several chemistries of Li-ion batteries reportedfor railway trains; they use liquid electrolytes and only twoanode materials: graphite and LTO. The main three rival Li-ion technologies for railway applications are: 1) NMC havinga graphite anode and NMC cathode; 2) LTO having an LTOanode and NMC cathode; and 3) lithium iron phosphate (LFP)having a graphite anode and LFP cathode. LTO has a fastercharging rate and a significantly higher number of cycles toEoL than NMC and LFP (i.e., superior cyclic life) [44], [45].On the other hand, LTO has a relatively lower energy densityattributed to the lower cell voltage (2.4 V) compared to NMC(3.7 V) and LFP (3.2 V) [46]. Regarding safety, theoretically,LFP is considered the safest of the three technologies sinceits cathode material (LFP) has the highest thermal runawaytemperature (270◦ C) compared to NMC and LTO (210◦C), which both have NMC cathodes. Recently, the rollingstock sector has been seeing a tendency toward LTO forOESDs due to the need to significantly cut down the batterycharging time and increase its lifetime, in this case compro-mising volume and weight [45], [47], [48]. On the other hand,some manufacturers are still going for NMC batteries to en-hance energy density like the case of Alstom for the CoradiaiLint [22], [49].