The cathode material is the focus of end-of-life lithium-ion battery recycling due to its high value. Cathode-to-cathode direct recycling avoids the need to change the cathode material to other metal forms, which could have significant economic and environmental advantages. A process that separates the cathode layer from current collector and recovers the active cathode materials is highly desirable as this facilitates the following regeneration step. In the present work, eutectic mixtures of lithium compounds are studies as an efficient and environmentally friendly approach for the separation and recovery of active cathode materials. Three commonly used inorganic lithium compounds i.e. LiCl, LiNO₃, and LiOH, and their binary eutectic systems are investigated. It is found that LiOH-LiNO₃ eutectic system has the highest peel-off efficiency. At temperature of 260 °C with 30 min holding time and salts/cathode electrode mass ratio of 10:1, up to 98.3% of cathode active materials can be recovered. The recovered cathode materials show minimal change and destruction on chemical composition, crystal structure, and morphology. Results suggest that LiOH-LiNO₃ eutectic system can facilitate the decomposition of polyvinylidene fluoride binder and capture the HF released. The process based on eutectic systems of lithium compounds provides an alternative binder removal approach to organic solvents, and offers re-lithiation benefit without introducing impurities. It has the potential to promote direct recycling and sustainable recycling of spent lithium-ion batteries.

正极材料因其高价值而成为使用寿命终止的锂离子电池回收的重点。阴极到阴极的直接循环利用避免了将阴极材料更改为其他金属形式的需要，这可能具有重大的经济和环境优势。非常需要将阴极层与集电器分离并回收活性阴极材料的方法，因为这有助于随后的再生步骤。在当前的工作中，锂化合物的共晶混合物被研究为分离和回收活性阴极材料的一种有效且环保的方法。研究了三种常用的无机锂化合物，即LiCl，LiNO ₃和LiOH，及其二元共晶体系。发现LiOH-LiNO ₃共晶体系具有最高的剥离效率。在260°C的温度下保持30分钟，盐/阴极电极的质量比为10：1，可以回收高达98.3％的阴极活性材料。回收的阴极材料在化学组成，晶体结构和形态上显示出最小的变化和破坏。结果表明，LiOH-LiNO ₃共晶体系可促进聚偏二氟乙烯粘合剂的分解并捕获释放的HF。基于锂化合物的共晶体系的方法为有机溶剂提供了一种替代性的去除粘结剂的方法，并且在不引入杂质的情况下提供了重新锂化的好处。它具有促进废锂离子电池的直接回收和可持续回收的潜力。