nmc cathode optimal particle size effect tap density

In this paper, the preparation and detailed characterization of porous hierarchically structured active materials with two different median secondary particle sizes, namely, 9 and 37 μm, and primary particle sizes in the range 300-1200 nm are presented.

To overcome these problems, the build-up of hierarchically structured active materials and electrodes consisting of microsized secondary particles with a primary particle scale in the nanometer range is preferable. However, nanomaterials are known to have extreme influence on gravimetric energy density and rate performance but are not used at the industrial scale because of their reactivity, low tap density, and diminished volumetric energy density. The latter one is at lowest for coarse-grained electrodes and seems to be a crucial quantity.Ībstract = 'Commercially used LiNi1/3Mn1/3Co1/3O2 (NMC111) in lithium-ion batteries mainly consists of a large-grained nonporous active material powder prepared by coprecipitation. Doing so, geometrical microstructure characteristics such as constrictivity quantifying the strength of bottleneck effects and descriptors for the lengths of shortest transportation paths are computed, such as the mean number of particles, which have to be passed, when going from a particle through the active material to the aluminum foil. For a better understanding of these results, that is, of process-structure-property relationships at both granule and electrode levels, 3D imaging is performed with a subsequent statistical image analysis. Moreover, electrodes of fine granules show an optimal electrochemical performance using NMC powders sintered at 900 ☌. In particular, electrodes of coarse granules sintered at 850 ☌ demonstrate more favorable transport parameters because of electrode build-up, that is, the morphology of the system of active material particles in the electrode, and demonstrate superior discharge capacity. Electrochemical investigations by means of rate performance tests show that hierarchically structured electrodes provide higher specific capacities than conventional NMC111, and the cell performance can be tuned by adjustment of processing parameters. Commercially used LiNi1/3Mn1/3Co1/3O2 (NMC111) in lithium-ion batteries mainly consists of a large-grained nonporous active material powder prepared by coprecipitation.

Nmc cathode optimal particle size effect tap density