Facile etching for single crystal cathode materials

US11827998B2 · kind B2 · utility

Assignee

• Worcester Polytechnic Institute · US

Inventors

• Yan Wang · Shrewsbury, US
• Xiaotu Ma · Worcester, US
• Eric Gratz · Worcester, US
• Jinzhao Fu · Worcester, US
• Panawan Vanaphuti · Worcester, US

Key dates

• Filing date: May 26, 2021
• Grant date: Nov 28, 2023
• Expiry date: Mar 2, 2042

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02W30/84
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

A recycling and synthesis of charge material for secondary batteries generates single-crystal charge materials for producing batteries with greater charge cycle longevity. Charge material particles undergo a heating for fusing or enhancing grain boundaries between polycrystalline particles. The resulting, more well-defined grain boundaries are easily etched by a relatively weak mineral acid solution. The acid solution removes material at the grain boundaries to separate secondary particles into primary particles along the grain boundaries. The resulting single crystal (monocrystalline) charge material particles are washed and filtered, and typically re-sintered to accommodate any needed lithium (lithium carbonate), and result in a charge material with larger surface area, higher lithium diffusivity and lower cation ordering.