Patent ID: 7972535

Claim:
Composite particles for an electrochemical device electrode comprising primary and secondary particles, wherein each of the primary and secondary particles contain an electrode active material, a conductive material, and a binder; wherein primary particles have a volume average particle size of 1 to 500 μm; wherein secondary particles are agglomerates of primary particles; wherein ρ 1 is defined as the volume percentage of primary particles having a particle size in the range of 10 (logR1)−α μm to less than 10 (logR1)+α μm relative to the total amount of primary particles at all particles sizes; wherein ρ 2 is defined as the volume percentage of secondary particles having a particle size in the range of 10 (logR1)−α to less than 10 (logR1)+α μm relative to the total amount of secondary particles at all particles sizes; wherein R 1 is defined as the primary particle size corresponding to the largest number of particles in a primary particle size distribution; α is 0.05 or less and, the ratio of ρ 2 to ρ 1 is 0.03 to 0.30 .