Nickel-Manganese Composite Hydroxide for High-Output Battery Cathodes

The positive electrode active material is divided into primary particles (50-200 nm) that aggregate into secondary particles (3-10 μm). This segmentation provides large surface area for high capacity while the aggregated structure facilitates ion transport for good output characteristics. The primary particles are formed through controlled precipitation with specific crystal orientation, and their aggregation creates a hierarchical structure that balances both capacity and power performance.

The invention employs a nested hierarchical structure where primary particles (50-200 nm) are nested within secondary particles (3-10 μm). The primary particles provide high surface area for fast reaction kinetics and good output characteristics, while the secondary particle aggregation increases volumetric energy density. This nested architecture allows small primary particles to be contained within larger secondary particles, simultaneously achieving both high power and high energy density.

The invention uses lithium-nickel-cobalt-manganese composite oxide with optimized composition ratios (0.8 ≤ x ≤ 1.0, 0.05 < y ≤ 0.3, 0 < z ≤ 0.3) to create a composite material that balances capacity and cost. The material combines nickel's high capacity with cobalt's stability and manganese's cost-effectiveness. The controlled precipitation process also enables efficient production at scale, improving ease of manufacture while maintaining high capacity performance.

The invention controls crystallinity by adjusting precipitation parameters including temperature (20-80°C), pH (9-12), and aging time (1-24 hours). These parameter changes enable control over the degree of crystallinity and crystal orientation without requiring complex post-processing steps. The controlled precipitation process directly forms particles with appropriate crystallinity during synthesis, avoiding additional manufacturing complexity while achieving high capacity.