About the design basis of lithium-ion power lithium-ion battery

1.1 The basic principles of power lithium-ion battery design. Power lithium-ion battery design is to supply working power or power source to the equipment according to the requirements of electrical equipment. Therefore, the design of power lithium-ion batteries must first determine the parameters of the battery’s electrodes, electrolyte, diaphragm, casing and other components according to the characteristics of the electrical equipment and the battery, optimize the process parameters, and compose them with certain specifications and Indicators (such as voltage, capacity, volume and weight, etc.) of the battery pack. Whether the design of the power lithium-ion battery is reasonable or not is related to the performance of the battery, and it is necessary to optimize the design as much as possible. 1.2 Design requirements for power lithium-ion batteries When designing power lithium-ion batteries, it is necessary to know the battery performance indicators and battery usage conditions of the electrical equipment. Generally, the following aspects should be considered: battery working voltage; battery working current, that is, normal discharge current And peak current; battery working time, including continuous discharge time, service life or cycle life; battery working environment, including battery working environment and ambient temperature; battery maximum allowable volume. Lithium-ion power lithium-ion batteries are used more and more widely due to their excellent performance. Sometimes they are used in some special occasions, so there are some special requirements, such as impact resistance, vibration resistance, high and low temperature resistance, and low air pressure. When considering the above-mentioned basic requirements, the source of materials, determinants of battery characteristics, battery performance, battery manufacturing process, technical and economic decomposition, and environmental temperature should also be considered. 1.3 Important indicators for evaluating the performance of power lithium-ion batteries The performance of power lithium-ion batteries is generally evaluated through the following aspects: capacity. Battery capacity refers to the amount of electricity that can be obtained from the battery under certain discharge conditions, that is, the integral of current over time, generally expressed in Ah, which directly affects the maximum working current and working time of the battery. Discharge characteristics and internal resistance. Battery discharge characteristics refer to the stability of the battery's working voltage, the level of the voltage platform, and the high-current discharge performance of the battery under a certain discharge system. It declares the ability of the battery to carry a load. The internal resistance of the battery includes ohmic internal resistance and electrochemical resistance. When a large current is discharged, the internal resistance has a particularly obvious influence on the discharge characteristics. range of working temperature. The working environment and use conditions of electrical equipment require batteries to have good performance within a specific temperature range. Storage performance. After the battery is stored for a period of time, the performance will change due to the influence of certain factors, which will cause the battery to self-discharge, electrolyte leakage, and battery short circuit. Cycle performance. Cycle life refers to the number of cycles when the secondary battery is charged and discharged in accordance with a certain system, and its performance decays to a certain level, which critically affects the battery's service life and safety performance. Critical refers to the battery's safety performance under the conditions of abuse. The abuse conditions include overcharge, short circuit, acupuncture, squeeze, hot box, heavy object impact, vibration, etc. The quality of the anti-abuse performance is determined The primary condition for whether the battery can be used in large quantities. 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 post: Introduction to lithium batteries and polymer lithium batteries