How to determine the capacity of a lithium-ion battery?

How to determine the capacity of lithium-ion batteries The traditional charging method is two-stage constant current charging, which does not waste electrical energy and has a short charging time, which is beneficial to prolong the service life of lithium-ion batteries. At the same time, calculating the capacity of lithium-ion batteries is much easier. Wind energy is different from traditional charging. Whether the lithium-ion battery capacity is reasonable or not directly affects the technical and economic indicators of wind power generation. The capacity selection is small, and the remaining power that appears when the wind is blowing is not completely stored. If the output is too large, a new investment; the second lithium-ion battery may be in a state of unsatisfactory charging for a long time, which will affect the efficiency and service life of the lithium-ion battery. Table 1 shows the investment of lithium-ion batteries in wind power equipment. 1. Relevant experience calculation According to our pilot experience, the following formula can also be used to simply estimate the battery capacity of the chayou and shangdu rear flag under wind conditions. In the formula: Q required lithium-ion battery capacity (amp hours); P load power (watts); T daily power consumption; U standard lithium-ion battery voltage (usually 12 volts); N battery reserve cycle coefficient; (according to The wind condition is determined, generally 3~8 days) K flow control coefficient, (0.75~0.8) above consideration: the rated power of the power equipment, the local weather conditions, that is, the average no wind time, in order to prevent the discharge of the lithium ion battery, the discharge should be controlled To a certain extent. Take the flag at the rear on the right as an example. A 100-watt machine was installed to supply electricity to three households. Install two 12-volt 15-watt light bulbs in each household for an average of 5 hours a day to calculate the required lithium-ion battery capacity. (The reserve factor is 6, and the flow control factor is 0.8) Substituting into the formula, we get: 6 2V 48A lithium-ion batteries with a total capacity of 288Ah. 2. Power balance calculation method. The calculation steps are as follows: A. According to the wind speed data provided by the local meteorological department, calculate the number of hours of different wind speeds from the start of the wind speed of the wind turbine to the wind speed of the wind speed when the wind turbine stops running, with a degree of 10 days. B. According to the characteristic curve (Pu003df(V)) of the selected wind turbine and wind speed data, calculate the amount of electricity that can be generated by the machine within 10 days, and draw the curve of its annual power generation process. The graph is based on the wind speed data of Inner Mongolia Youhou Banner. The annual power generation process line of the ED1.5~100 wind turbine of Shangdu Animal Husbandry Engine Factory is drawn. According to calculations, the annual power generation capacity of this unit under local wind conditions is 276°C. It can be seen from the process line that the power generation every ten days will be very different. The maximum is 19 degrees in late April, and the minimum is 0.95 degrees at the end of February. The difference is nearly 20 times, which indicates that it is necessary to configure lithium-ion battery energy storage. Supervision. C. According to the usage of telecommunications, calculate the electricity consumption every 10 days and give the annual electricity consumption processing line. The dotted line in the figure is as shown in the figure. D. Compare the power generation and consumption process lines, and determine the required lithium-ion battery capacity according to the power generation during the period when the power generation is less than the maximum power difference (diagonal line in the figure). The biggest difference in the figure is 2.3 degrees. It needs to be equipped with 2300 volt-ampere batteries, and actually uses four 12-volt 48-amp lithium-ion batteries. The total capacity is 2304 voltammetry. When determining the standard battery, it should be noted that the capacity of the storage unit should be able to safely accept the maximum current intensity Imax present in the wind turbine. Because the wind speed often changes, the output current of the motor is large, small, and sometimes not, so it is difficult to determine the charging current and the required lithium-ion battery charging time. In view of this actual situation, we use the following two calculation methods to determine the configured lithium-ion battery capacity. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete.