STUDY OF THE EFFECT OF BINDER MATERIAL CHOICE ON THE ELECTROCHEMICAL PROPERTIES OF LaNi₅ BASED ANODES

With growing demands for environmental sustainability and efficiency in energy storage systems, nickel-metal hydride (Ni-MH) batteries continue to attract attention due to their safety and affordability. Optimization of components in such batteries is a priority task for improving their electrochemical characteristics and durability. One of the key components is anodes based on hydrogen-forming alloys, whose electrochemical properties, such as stability and capacity, significantly depend on the choice of binder material, which affects the structural integrity, conductivity, and resilience of the anode during cyclic charging and discharging. This paper investigates the influence of various polymer binders on the electrochemical properties of anodes based on LaNi₅ for Ni-MH batteries. The LaNi₅ alloy was synthesized using the solid-phase method from metal oxides, and its structure was confirmed by X-ray phase analysis. Electrodes were fabricated using three types of binders: polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVdF), and  polyethylene (PE). The electrochemical characteristics of the anodes were studied using cyclic voltammetry and galvanostatic charge-discharge methods. Results showed that the type of binder substantially affects the electrical conductivity, capacity, and cycling stability of the electrodes. Anodes with PTFE binder demonstrated the best electrochemical characteristics, high specific capacity (~200 mAh/g), and stability during multiple cycling. Electrodes with PE showed high initial capacity but rapid degradation during cycling, while anodes with PVdF were characterized by stable but low capacity. The study confirms that the choice of binder material is crucial for optimizing the performance of Ni-MH batteries. 

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