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The chemical stability of cefixime was determined by high-performance liquid chromatography (HPLC) under different conditions, including factors such as pH, solvents, initial concentration, temperature and additives. The degradation process follows the first-order kinetics. A pH-rate profile exhibits the U-shape and shows the maximum stability of cefixime at pH = 6. The stability in different pure solvents is ranked as acetone > ethanol > methanol > water, while the degradation rate of cefixime exists a maximum at the ratio of 0.6 in water + methanol mixtures. In addition, the degradation rate increases with the temperature increasing and the activation energy of degradation was found to be 27.078 kJ·mol−1in acetone + water mixed solvents. The addition of different additives was proven to either inhibit or accelerate the degradation. The degradation products were analyzed using HPLC, LC–MS and infrared spectroscopy, and the possible degradation pathways in acid as well as alkaline environment were proposed to help us understand the degradation behavior of cefixime.

•The influence of ultrasound on nucleation of cephalexin monohydrate was studied.•The nucleation mechanism was discussed qualitatively and quantitatively.•Different crystallization conditions were tested to improve the product quality.•The optimal policy could achieve crystal habit control effectively.

With the development of digital products, electric vehicles and energy storage technology, electronic chemicals play an increasingly prominent role in the field of new energy such as lithium-ion batteries. Electronic chemicals have attracted extensive attention in various fields. Characteristics of high-end electronic chemicals are high purity and low impurity content, which requires a very strict separation and purification process. At present, crystallization is a key technology for their separation and purification of electronic chemicals. In this work, the representative fluorine-containing compounds in cathode and anode materials, separator and electrolyte of lithium-ion batteries are introduced. The latest technologies for the preparation and purification of four kinds of fluorine-containing battery chemicals by crystallization technology are reviewed. In addition, the research prospects and suggestions are put forward for the separation of fluorine-containing battery chemicals.