What is the energy density of LFP and NMC cells?

If we focus on the major trends, we can highlight an energy density range from 90 to 130 Wh/kg for LFP chemistry and from 190 to 260Wh/kg for NMC ones. Figure 1. Energy densities of various LFP and NMC cells: volumetric energy density as a function of energy density also called specific density; source: [CEA-Liten].

Are NMC and LFP cells intrinsically protected against thermal runaway?

However, we can point out that both NMC and LFP cells are subject to thermal runaway phenomenon, and not intrinsically protected against it as it is suggested by some. Also, due to the voltage range of NMC cells compared to LFP cells (see Figure 2), NMC chemistry is more likely to experince to the Li-plating.

What is the SOC estimation uncertainty for NMC vs LFP cells?

Figure 2.b. shows that, at the same dV, SOC estimation uncertainty for the NMC cell is around 8% and 49% for the LFP one. In fact, it is hard to accurately measure a LFP cell voltage evolution during its quasi non-changing phase. The slightest voltage measurement error during this phase could lead to SOC aberrant estimation.

Do C/LFP cells run away more violently than C/NMC cells?

Consequently, C/LPF cells tend to reach thermal runaway level later than C/NMC ones. On the other hand, Figure 5. clearly shows that the rate of temperature change during a thermal runaway, observed at 130°C, increases with the energy density. As a result, C/LFP cells tend to run away less violently than C/NMC ones.