Low-Temperature Ion Exchange Synthesis of Layered LiNiO2 Single Crystals with High Ordering

• DOI: 10.1021/acs.chemmater.2c03203
• Publication Date: 2023-01-04T17:19:35Z
• Authors: Leonhard Karger; Daniel Weber; Damian Goonetilleke; Andrey Mazilkin; Hang Li; Ruizhuo Zhang; Yuan Ma; Sylvio Indris; Aleksandr Kondrakov; Jürgen Janek; Torsten Brezesinski
• Keywords: Stoichiometry; Ionic radius

Layered Ni-rich oxide cathode materials are being explored in an effort to boost the energy density of lithium-ion batteries, especially for automotive applications. Among them, ternary-phase LiNiO2 (LNO) is a promising candidate but brings along various issues, such as poor structural stability. The material prone disordering (Li off-stoichiometry) when prepared by conventional solid-state synthesis, leading presence Ni2+ Li layer. These point defects negatively affect utilization inventory, thereby limiting practical specific capacity. In this work, we report on two-step synthesis approach that avoids formation nickel substitutional defects. First, NaNiO2 (NNO) prepared, showing no due larger differences ionic radii between Ni2+/Ni3+ and Na+. NNO then subjected Na+/Li+ exchange under mild conditions. so doing, monolithic LNO particles free NiLi• can be produced at relatively low temperatures. Notably, route allows tailoring grain size, strategy may used gain insights into structure–size–property relations single-crystalline LNO.