The Impact of Waviness on Percolation Onset in Lithium-Ion Battery Cathodes

Lithium-ion batteries have become a crucial component in modern electric vehicles and renewable energy systems due to their high energy density and long lifespan. The cathode material plays a vital role in determining the overall performance of these batteries. In recent years, researchers have been exploring novel concentration-gradient cathode materials for high-energy lithium-ion batteries.

One such material is the nano-functional full-gradient cathode material developed by ĭunn et al. This innovative material features a nickel-rich core with a manganese-rich outer layer, resulting in a high rate capability and excellent thermal stability. The micrometre-size secondary particles are composed of aligned needle-like nanosize primary particles, allowing for efficient charge transfer.

The use of this nano-functional full-gradient approach enables the harnessing of the high energy density of the nickel-rich core and the long life of the manganese-rich outer layers. In a recent study, researchers reported a nickel-rich lithium transition-metal oxide with a capacity of 215 mA h g-1, where the nickel concentration decreases linearly and the manganese concentration increases linearly from the centre to the outer layer of each particle.

However, commercial deployment of nickel-rich oxides has been hindered by their intrinsic poor thermal stability at the fully charged state and insufficient cycle life, especially at elevated temperatures. This has led researchers to investigate alternative cathode materials with improved thermal stability and lifespan.

Nickel-rich layered lithium transition-metal oxides, LiNi1-xMxO2 (M = transition metal), have been under intense investigation as high-energy cathode materials for rechargeable lithium batteries due to their high specific capacity and relatively low cost. These materials offer a promising solution for the development of advanced lithium-ion battery cathodes with improved thermal stability and lifespan.

In conclusion, the effect of waviness on percolation onset in lithium-ion battery cathodes is an important aspect of research in this field. The development of novel concentration-gradient cathode materials like the nano-functional full-gradient material offers a promising solution for the creation of high-energy and safe lithium-ion batteries. Further research is needed to overcome the challenges associated with commercial deployment of these materials.

Li ion battery cathode