Do you know what battery capacity (Ah) is?

Battery capacity refers to the amount of power, which can also be understood as volume. Below, we will understand the detailed meaning of battery capacity in terms of battery capacity unit, battery capacity calculation, battery capacity test, and battery capacity kwh. What are the battery capacity (Ah)? 1. Battery capacity unit The capacity unit of lithium battery is milliampere hour, ampere hour, watt hour. Expressed in accordance with: milliampere hour mah (MAH); ampere hour ah (AH); watt hour Wh. In layman's terms, the physical meaning of battery capacity refers to how much charge the battery can hold or release. We often use Ah (Ampere hour) or mAh (Milliamp hour) to express. According to the meaning of current: Iu003dQ/t, we can see that Qu003dIt, the unit of current I is mA (milliampere), t represents time, the unit is hour (hour), so our battery capacity unit is mAh. That is to say, if the capacity of a battery represents 1000mAh, if the current when it is working is 100mA, it can theoretically supply power for 10 hours. However, we can see from the formula that Qu003dIt, and no voltage is involved, so this unit can only indicate how many coulombs of charge can be accommodated inside the battery. But it cannot tell how much work this battery can do, and what the maximum power the battery can supply. The working voltage of different types of products is different. Therefore, we often see that there is a number in Wh next to mAh. The work that the battery can do Wu003dUItu003dUQ, and the unit of voltage U*current I is W (watts), so W in the battery is represented by Wh, which indicates how much work the battery can do. 2. Calculation of battery capacity. Calculation method of battery capacity (C): capacity C u003d discharge battery (constant current) Ix discharge time (hours) T in turn: discharge time T u003d capacity C/discharge current (constant current) I such as a battery With a constant current of 500MA (milliampere) for 2 hours, then the capacity of the battery is equal to 500MA*2Hu003d1000MAHu003d1AH. If a battery is discharged with a current of 5A for 2 hours, then the capacity of the battery is 10AH. 3. Conversion of battery capacity and power. From the perspective of the unit, the unit of power is watt (W), which is clearly defined by Pu003dUI, 1Wu003d1V.A (one watt is equal to one volt-ampere) battery capacity mA.h (milliampere hour) The two parts are different. Further look for the relationship: the unit of electric energy and work Joule (J) can be known from Wu003dPt: 1.Ju003d1W.su003d1V.As (one joule is equal to one volt-ampere second) If the battery voltage is known, multiply the voltage by the voltage What do you see about the battery capacity: The unit VmAh is actually the same as the unit of electric energy. Conversion: 1V.mA.hu003d1V*10^-3A*3600su003d3.6VAsu003d3.6.7 What does the battery capacity kwh mean? The rated capacity C of the unit is ampere hour (Ah), which is the product of the discharge current ampere (A) and the discharge time hour (h). Since the Ah obtained by using different discharge parameters for the same battery is different, in order to facilitate the description, measurement and comparison of battery capacity, uniform conditions must be set in advance. In practice, battery capacity is defined as: discharge the battery with a set current to the amount of power given by the set voltage. It can also be said that the battery capacity is the product of the time it takes to discharge the battery to the set voltage with a set current and this current. In order to set uniform conditions, first, according to the differences in battery structure and usage, a number of discharge time rates are set. The most common ones are 20 hours, 10 hours, and 2 hours for electric vehicle batteries, written as C20 , C10 and C2, where C represents the battery capacity, and the following number indicates the number of hours that this type of battery is discharged to the set voltage with a certain intensity of current. Then, divide the number of hours by the capacity to get the rated discharge current. In other words, the nominal discharge current of batteries with the same capacity but different discharge rates is far different. For example, the battery capacity of an electric bicycle is 10Ah, and the discharge rate is 2 hours, written as 10Ah2, its rated discharge current is 10(Ah)/2(h)u003d5A; and the battery capacity for starting a car is 54Ah , The discharge time rate is 20 hours, written as 54Ah20, its rated discharge current is only 54 (Ah) / 20 (h) u003d 2.7A! To put it another way, if these two batteries use 5A and 2.7A current respectively Discharge, it should be able to continue for 2 hours and 20 hours respectively before dropping to the set voltage. 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: What are the important parameters of lithium batteries?