What factors will affect the capacity of the battery?

There are many factors that affect the battery capacity, and the common ones are the following: (1) The influence of temperature on the battery capacity The temperature has a greater influence on the capacity of the lead-acid battery. Generally, as the temperature drops, the capacity decreases, and the relationship between capacity and temperature is as follows: :Ct1u003dCt2/1+k(t1-t2).t1t2 is the temperature of the electrolyte, k is the temperature coefficient of the capacity, Ct1 is the capacity when the temperature is t1 (Ah), and Ct2 is the capacity when the temperature is t2 (Ah) In the battery processing standards, it is generally necessary to specify a temperature as the rated standard temperature. For example, it is specified that t1 is the actual temperature and t2 is the standard temperature. (generally 25 degrees Celsius) the negative plate is more sensitive to the influence of low temperature than the positive plate. When the electrolyte temperature When it decreases, the viscosity of the electrolyte increases, the ions receive greater resistance, the diffusion ability decreases, and the resistance of the electrolyte increases, which increases the resistance of the electrochemical reaction, and part of the lead sulfate cannot be converted normally. The charge acceptance ability decreases, resulting in the battery The capacity drops. (2) The influence of the discharge rate on the battery capacity. The battery capacity decreases with the increase of the discharge rate, that is to say, the larger the discharge current, the smaller the calculated battery capacity. For example, a 10Ah battery uses 5A Discharge can be put for 2 hours, that is, 5×2u003d10; then only 47.4 minutes of electricity can be discharged with 10A discharge, which is 0.79 hours. Its capacity is only 10×0.79u003d7.9Ah. So about the given battery at different time rates Under discharge, there will be different capacities. When we talk about capacity, we must know the time rate or rate of discharge. Simply put, how much current is used to discharge. (3) The impact of the termination voltage on the battery capacity. When the battery is discharged to a certain voltage value, the voltage drops sharply. In fact, the energy obtained is very small. If the battery is discharged for a long time, the damage to the battery is considerable. Therefore, it must be A voltage value terminates the discharge, and the cut-off discharge voltage is called the discharge termination voltage. Setting the discharge termination voltage is of great significance to prolong the service life of the battery. Generally, the discharge termination voltage of the electric vehicle battery that we repair is 1.75 volts per cell That is to say, a 12-volt battery has 6 cells, and its end-of-discharge voltage is 6×1.75u003d10.5 volts. (4) The geometrical size of the plate affects the capacity of the battery when the amount of active material is on time, it is directly related to the electrolyte. The geometric area of u200bu200bthe contact plate increases and the battery capacity increases, so the geometric size of the plate has an impact on the battery capacity. ①The influence of the plate thickness on the capacity The amount of active material is constant, and the battery capacity varies with the plate thickness. The thicker the plate, the smaller the contact surface between the sulfuric acid and the active material, the lower the utilization rate of the active material, and the smaller the battery capacity. ②The influence of the height of the plate on the capacity is in the battery, the upper and lower sides of the plate There is a big difference in the utilization rate of the two parts of the active material. Experiments have confirmed that at the beginning of the discharge, the current density of the upper part of the electrode plate is about 2 to 2.5 times higher than that of the lower part. This difference gradually decreases with the passage of the discharge. However, the upper part has a higher current density than the lower part. ③The influence of the plate area on the capacity of the lithium battery The amount of active material is certain, the larger the geometric area of u200bu200bthe plate, the higher the utilization rate of the active material, and the larger the capacity of the battery. When the shell is the same and the quality of the active material remains the same, the number of new plates is added using the thin plate, that is, the effective reaction area of u200bu200bthe plate is added, which improves the utilization rate of the active material and increases the capacity of the battery. . 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 article: Why are lithium batteries so popular?