High-nickel cathode materials have become a focal point in advanced lithium-ion battery development due to their potential for higher energy density and reduced reliance on cobalt. The compositional innovations in these materials have led to numerous patents and intellectual property trends, particularly around stabilizing the structure, enhancing cycle life, and improving safety. Below is a detailed exploration of key patents and IP trends in this domain.

One major area of innovation involves the modification of high-nickel layered oxides (LiNi_xMn_yCo_zO₂, where x > 0.6). A prominent approach is the incorporation of dopants to mitigate cation mixing and oxygen loss, which are primary degradation mechanisms. Patents from companies like Panasonic and LG Chem disclose the use of aluminum, magnesium, and titanium as dopants. These elements integrate into the crystal lattice, reducing Ni²⁺ migration into Li sites and improving thermal stability. For instance, a patent by Panasonic describes an Al-doped LiNi₀.₈Co₀.₁₅Al₀.₀₅O₂ (NCA) cathode that exhibits enhanced capacity retention after 500 cycles compared to undoped variants.

Another significant trend is the development of core-shell and concentration-gradient structures. Samsung SDI holds patents on high-nickel cathodes with a Ni-rich core and a Mn-rich outer layer, which suppresses interfacial reactions with the electrolyte. The concentration-gradient design gradually transitions from a high-energy-density core to a more stable shell, balancing performance and longevity. A notable example is LiNi₀.₇Co₀.₁₅Mn₀.₁₅O₂ with a Ni-rich core (Ni > 0.8) and a Mn-rich surface (Mn > 0.3), which demonstrates reduced gas evolution during cycling.

Surface coating technologies are also widely patented. Companies such as CATL and Tesla have filed patents on applying nanoscale coatings of oxides (e.g., Al₂O₃, ZrO₂) or phosphates (e.g., Li₃PO₄) onto high-nickel particles. These coatings act as barriers against electrolyte decomposition and HF attack, which are critical for prolonging cycle life in high-voltage operations. A Tesla patent highlights a dual-layer coating of Al₂O₃ followed by carbon, which improves conductivity while preventing surface degradation.

Compositional innovations extend to hybrid high-nickel systems. BASF and Umicore have patented materials combining high-nickel cathodes with spinel or lithium-rich phases to leverage synergistic effects. For example, a BASF patent describes a composite cathode with 80% LiNi₀.₈Mn₀.₁Co₀.₁O₂ and 20% Li₁.₂Mn₀.₆Ni₀.₂O₂, delivering both high capacity and structural stability. Such hybrids aim to address the trade-offs between energy density and cycle life.

The push for ultra-high-nickel cathodes (Ni > 90%) has also generated substantial IP activity. Toyota and SK Innovation have disclosed patents on LiNi₀.₉Mn₀.₀₅Co₀.₀₅O₂ with specialized sintering processes to achieve uniform particle morphology. These materials require precise control over oxygen partial pressure during synthesis to prevent Li/Ni disorder. SK Innovation’s patents emphasize co-precipitation methods to produce spherical secondary particles with minimized microcracking.

Stabilizing the delithiated state of high-nickel cathodes is another critical challenge addressed in patents. POSCO holds IP on fluorine substitution in the oxygen lattice (e.g., LiNi₀.₈Co₀.₁Mn₀.₁O₂₋ₓFₓ), which strengthens the framework against oxygen release during deep charging. Similarly, patents from Hitachi describe the use of boron doping to form a robust surface layer that resists crack propagation under mechanical stress.

In terms of electrolyte compatibility, patents from BYD and AESC highlight the integration of high-nickel cathodes with specialized electrolytes containing additives like vinylene carbonate and lithium difluorophosphate. These formulations passivate the cathode surface, reducing impedance growth and transition-metal dissolution. AESC’s patents particularly focus on sulfonate-based additives that form a stable cathode-electrolyte interphase (CEI).

Recent IP trends also reflect efforts to reduce cobalt content further while maintaining performance. Patents from Northvolt and Svolt reveal cobalt-free high-nickel formulations such as LiNi₀.₉Mn₀.₁O₂, where manganese partially substitutes cobalt. These materials rely on advanced doping strategies to compensate for the loss of cobalt’s beneficial effects on electronic conductivity and structural integrity.

The synthesis methods for high-nickel cathodes are equally patented. Umicore’s IP portfolio includes hydrothermal synthesis techniques for producing single-crystal high-nickel cathodes, which exhibit superior mechanical strength compared to polycrystalline counterparts. Single-crystal particles mitigate grain-boundary-related degradation, a common issue in high-nickel systems.

Safety remains a paramount concern, leading to patents on thermally stable high-nickel compositions. LG Energy Solution has developed materials with integrated oxygen scavengers, such as rare-earth elements (e.g., La, Y), which bind released oxygen during thermal runaway. Another approach, patented by CALT, involves incorporating flame-retardant agents like phosphazenes into the cathode matrix.

The IP landscape also reveals a growing emphasis on scalable and cost-effective production methods. Patents from Farasis Energy detail roll-to-roll electrode fabrication for high-nickel cathodes, optimizing slurry rheology and drying protocols to prevent cracking in thick electrodes. Similarly, patents from GEM Co. focus on recycling-derived high-nickel materials, where recovered metals are reprocessed into cathode precursors with minimal performance loss.

In summary, the patent trends in high-nickel cathode materials highlight a multi-faceted approach to overcoming their inherent challenges. Key innovations include dopant integration, core-shell architectures, surface coatings, hybrid systems, ultra-high-nickel formulations, and advanced synthesis techniques. These developments collectively aim to enhance energy density, cycle life, and safety while reducing reliance on costly and scarce elements like cobalt. The IP activity underscores the industry’s focus on both performance optimization and manufacturability, paving the way for next-generation lithium-ion batteries.