Is the internal resistance of the 18650 lithium battery pack large or small?

Is the internal resistance of the 18650 lithium battery pack large or small? Inside the lithium battery, lithium ions move from one pole to the other, and the factors that hinder the movement of ions in the process collectively constitute the internal resistance of the lithium battery. The important parts include the physical internal resistance of conductive parts; the inherent impedance of electrochemical substances such as motor materials, diaphragms and electrolytes; the temporary new obstacle to the movement of lithium ions when current flows inside the battery; these three parts together constitute The main body of internal resistance. The internal resistance of the 18650 lithium battery pack is the most sensitive to temperature, and the internal resistance value can vary greatly at different temperatures. One of the important reasons for the degradation of battery performance at low temperature is the excessive internal resistance of the battery at low temperature. The 18650 lithium battery pack is used as a power source. From the outside, the internal resistance must be as small as possible. Especially in the case of power applications, small internal resistance is a necessary condition. The larger the capacity, the larger the area and the smaller the resistance through which the current flows. The internal resistance of the lithium battery pack must be as small as possible. The smaller the internal resistance, the less power is wasted for the battery, and it is helpful for the heat generation and rate of the battery. In recent years, new energy vehicles have increasingly higher requirements for high-rate charge and discharge performance of power lithium-ion batteries, and internal resistance is an important factor affecting battery power performance and discharge efficiency. With the use of 18650 lithium battery packs, battery performance continues Attenuation is mainly manifested as capacity attenuation, increase in internal resistance, power drop, etc. The change in battery internal resistance is affected by various operating conditions such as temperature and depth of discharge. Internal resistance is an important parameter to measure the power performance of lithium batteries and evaluate battery life. The greater the internal resistance, the worse the rate performance of the battery, and the faster it is added in storage and recycling. The internal resistance is related to the battery structure, battery material characteristics and manufacturing process, and changes with changes in ambient temperature and state of charge. Therefore, the development of low-resistance batteries is the key to improving battery power performance, and at the same time, mastering the changing law of battery internal resistance has very important practical significance for battery life prediction. The internal resistance of the 18650 lithium battery pack is high and cannot be discharged at a large current. The lower the theoretical internal resistance, the better, and the internal resistance is directly related to the capacity. The general lithium battery assumes 1 ampere hour, the internal resistance is about 30 to 80 milliohms, while a good power lithium battery can be below 15 milliohms. The internal resistance of the lithium battery is high, and the battery heats up higher when discharging. In short: the lower the internal resistance of the lithium battery, the better. 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: How to charge and discharge lithium battery packs?