This invention introduces a niobium-modified ε-VOPO₄ cathode that achieves its full 305 mAh/g theoretical capacity with 98% coulombic efficiency. Featuring a stable 3D tunnel structure, dual voltage plateaus, and enhanced cycling durability, it enables high-performance, low-cost lithium batteries for EVs, grid storage, and advanced electronics.
Background: Lithium-ion batteries are essential for electric mobility, renewable energy storage, and portable electronics, but current cathode materials face critical trade-offs. Most cannot reach theoretical capacities, degrade under repeated cycling, or rely on cobalt and nickel, which are expensive and geopolitically constrained. These limitations have created a bottleneck for scaling next-generation batteries. A new material solution is needed to achieve higher energy density, cycle stability, and manufacturing scalability without increasing cost.
Technology Overview: This invention leverages the epsilon polymorph of vanadyl phosphate (ε-VOPO₄), synthesized solvothermally from H₂VOPO₄. The material’s 3D tunnel structure supports reversible two-lithium ion intercalation per vanadium atom, delivering a theoretical capacity of 305 mAh/g with 98% coulombic efficiency. Voltage plateaus at ~4.0 V and ~2.5 V allow dual-mode operation, providing flexibility for different power needs. Niobium surface modification strengthens structural durability, mitigates capacity fade, and improves cycling stability. The cathode’s design supports scalable electrode fabrication, offering a lower-cost, cobalt- and nickel-free pathway for next-generation lithium battery systems.
Advantages: • High theoretical capacity of 305 mAh/g via two-lithium ion intercalation • Dual voltage plateaus (~4.0 V and ~2.5 V) enable flexible power delivery • Niobium modification enhances durability and mitigates cycling degradation • Stable 3D tunnel structure resists breakdown across repeated cycles • Cobalt- and nickel-free composition lowers material costs and supply risks • High coulombic efficiency (98%) for energy retention and long cycle life • Compatible with lithium-ion and lithium-metal battery platforms
Applications: • Smart reserve power for medical and military electronics • Dual-mode EV powertrains with primary and backup operation • Grid-scale renewable energy storage and frequency regulation • Portable consumer electronics requiring extended run times • Robotics, aerospace, and critical mission electronics
Intellectual Property Summary: • US Utility Patent Application 18/447,278 – Filed August 9, 2023 • US Published Application US 2024/0006612 A1 – Published March 5, 2024
Stage of Development: Lab validation – Coin cell prototypes demonstrated theoretical capacity, dual-voltage operation, and cycling stability with niobium surface modification. TRL ~4.
Licensing Status: This technology is available for licensing.
Licensing Potential: Attractive to EV manufacturers, grid energy storage providers, and consumer electronics companies seeking high-energy-density, cobalt-free cathodes with scalable manufacturing potential.
Additional Information: Prototype cycling data, niobium surface modification results, and electrode fabrication methods available upon request.
Inventors: Krystal Lee, Carrie Siu, M. Stanley Whittingham, Fengxia Xin