What are the important factors that affect the performance of nickel-metal hydride batteries

1) Electrode active material of nickel-hydrogen battery The electrode active material determines the theoretical capacity of the electrode and the equilibrium potential of the electrode, thereby determining the battery capacity and battery electromotive force. The theoretical capacity of the electrode refers to the amount of electricity calculated according to Faraday's law that all active materials participate in the flow reaction of the battery. In addition to the higher theoretical capacity and the more positive (positive) or negative (negative) balance potential of the battery active material, it also requires the active material to have a suitable crystal type, particle size, surface state, etc., so as to obtain higher activity . Moreover, when the battery is open, the active material should have good stability, and it will not have any use with the components in the battery. (2) Electrolyte of nickel-hydrogen battery The electrolyte is one of the important components of the battery. The properties of the electrolyte (freezing point, boiling point, melting point, etc.) directly determine the battery's operating temperature range. Improving the properties of the electrolyte can expand the battery operating temperature range and improve the battery's high and low temperature performance. The specific conductance of the electrolyte directly affects the internal resistance of the battery. Generally, the higher specific conductance should be selected. But you should also pay attention to the battery's operating conditions, such as working at low temperatures, but also consider the freezing point of the electrolyte. Regarding the non-aqueous organic solvent electrolyte, the larger the dielectric constant of the electrolyte, the better, and the smaller the viscosity, the better. The electrolyte must be stored in the battery for a long time, so it is required to have good stability. When the battery is open, the electrolyte does not react. (3) The basic requirement for the diaphragm chemical power supply of nickel-hydrogen battery is to have sufficient chemical stability and electrochemical stability. It has a certain degree of alkali resistance, corrosion resistance, sufficient isolation and electronic insulation. Ensure the mechanical separation of the positive and negative electrodes and prevent the migration of active materials, have sufficient liquid absorption and moisture retention capacity and ionic conductivity, and ensure good ionic conductivity for positive and negative injection. In addition, it must have good air permeability, sufficient mechanical properties and shock resistance. The above properties of the separator have important effects on the battery's internal resistance, discharge characteristics, storage performance, self-discharge, cycle performance, internal pressure, and overcharge resistance performance. A reasonable choice of the type and thickness of the separator is particularly important for battery performance. . Commonly used in MH-Ni batteries are polypropylene felt diaphragm, polyamide diaphragm and so on. (4) Electrode preparation process of nickel-hydrogen battery The manufacturing methods of electrode include powder pressing method, paste coating method, sintering method and deposition method. Different manufacturing methods have their own characteristics. The pressing method is simple in equipment, convenient to operate, and more economical, and can be used in general battery series; the paste method is also common, and the battery made by the paste method has a longer life and less self-discharge; The sintered electrode has a long life and good high-current discharge performance. The electrodeposited electrode has a high porosity, a large specific surface area and high activity, which is suitable for high-power and rapid activation of batteries. In the electrode preparation process, it is often necessary to add some conductive agents, dispersants, liquid retention agents and additives to the active material to increase the utilization rate of the active material and improve the electrode conductivity, thereby increasing the actual capacity of the electrode and the discharge performance of the battery , Cycle performance, etc. Electrode preparation technology is often the key and core of battery manufacturing technology. Disclaimer: Some pictures and content of articles published on this site are from the Internet, if there is any infringement, please contact to delete. Previous: Analysis of cylindrical lithium battery model specifications