Main Advantages: single crystal, long cycling life, good cycling performance at high temperature, high power
Appearance: Black powder
Molecular Formula: LiNi0.6Mn0.2Co0.2O2 NMC (Ni:Mn:Co = 6:2:2)
Chemical Name or Material: Lithium Nickel Manganese Cobalt Oxide
Tap density: ≥1.6 g/cm3
Compaction density: 3.4 ~ 3.55 g/cm3
BET Specific Surface Area: 0.3 - 0.9 m2/g
First Discharge Capacity (0.5C, button half open cell vs. Li): ≥180 mAh/g (4.3 - 2.75V)
Questions and Answers
Q What can affect the stability of NMC when cycled to high voltages?
A The stability of NMC is affected by
structural transformation from layered to spinel and/or rock-salt phases
mechanical damage such as crack formation in active particles
parasitic reactions between cathode and the electrolyte
migration, segregation and dissolution of transition metals
Q Why do single crystals matter?
A The benefits of single crystal cathode materials:
Coatings on single crystal particles remain intact with repeated cycling
less undesirable side reactions with the electrolyte
long lasting and durable lithium ion battery cells
high gravimetric energy density and high volumetric energy
Q Why single crystal NMC is trending in EV industry?
A As battery is the most expensive component of EV, not only does battery health affect the vehicle’s residual value, but it also has a direct impact on the maximum usable range over time. The cycling life of battery using traditional NMC is usually shorten in an extreme weather condition. Single crystal NMC with better structure stability is a promising cathode material for long life time EV applications. The Tesla researchers patented a single crystal NMC which can be cycled for more than 4000 cycles at 40 °C.
1. A Wide Range of Testing Results on an Excellent Lithium-Ion Cell Chemistry to be used as Benchmarks for New Battery Technologies, J. Electrochem. Soc, 166(13) A3031-A3044 (2019)
2. Tesla battery researcher unveils new cell that could last 1 million miles in ‘robot taxis’, https://electrek.co/2019/09/07/tesla-battery-cell-last-1-million-miles-robot-taxis/
3. Single-crystal based studies for correlating the properties and high-voltage performance of Li[NixMnyCo1−x−y]O2 cathodes, J. Mater. Chem. A, 2019,7, 5463-5474