Lithium battery capacity test method
There are many methods to test the capacity of lithium batteries. The main reason for testing the capacity of lithium batteries is to see if the manufacturer has a false standard capacity, to see whether the battery products of the battery manufacturer are reliable, and to see whether the actual capacity of the lithium battery can meet the design. Product power parameter requirements?
Here are a few simpler lithium battery capacity test methods:
1. The method of actual use to test the capacity of lithium battery
The lithium battery capacity test is based on the full-charge voltage and the set termination voltage as the parameters. Because the minimum discharge voltage of the lithium battery is 2.75V, the voltage less than 3V has no meaning for the lithium battery test; the fixed current discharge generally uses how much C indicates that lithium batteries are generally tested with 0.5C discharge.
Fully charge the battery, the voltage after a single lithium battery is fully charged is 4.2V; with a multimeter, the lithium battery has a constant current of 0.5C, relative to the battery capacity, the termination voltage is set to 3v; the time for constant current discharge Multiplying by the discharge current is the battery capacity; check: if the constant current discharge cannot reach two hours, then the nominal voltage is not enough, and the lithium battery may be counterfeit. There is a professional lithium battery sub-capacitor. If you are an individual, find an adjustable load resistance and an adjustable current DC power supply to calculate the battery capacity through the charging and discharging time, charging current × charging time = battery capacity (Charge from 2.7V or 3.0V to 4.2V) or discharge current × discharge time = battery capacity.
2. Use the formula to calculate and estimate the capacity of lithium batteries
The capacity of a lithium battery is related to the model size and depends on the thickness, width and length of the battery. It is also related to the material and size of the battery. The actual calculation formula of polymer lithium battery capacity is very complicated, and the relationship with volume is not linear. Many factors need to be considered, such as different materials, which have a great impact on the actual capacity. The larger the size, the larger the capacity/volume ratio.
To quickly estimate the capacity of a polymer battery, the commonly used estimation formula (for estimation only):
Capacity = thickness * width * length * K (K unit is mah/mm3)
The range of K value is (0.07~0.11). The K value depends on the material industry and the size of the capacity. The larger the capacity, the larger the K value, the smaller the capacity, and the smaller the K value (it can be understood as the larger the size, the higher the K value. Big). In actual calculations, the K value can be set to 0.1 by default. For example, 103450LP (thickness 10mm, width 34mm, length 50mm), calculated capacity=10*34*50*0.1=1700, the actual capacity is above 1800mah; for example, 603048LP (thickness 6mm, width 30mm, length 48mm), calculated capacity=6* 30*48*0.1=864, the actual capacity can be 900mah.
The above are two simple and commonly used lithium battery capacity test methods. From the perspective of accuracy, it is obvious that the lithium battery capacity tested by the first method is more accurate, while the second method is worse. After all, it is theoretical. It is estimated that there are many factors affected, and from the point of view of convenience, it is obvious that the second method is more convenient, because basically no tools are needed, as long as you know the volume of the lithium battery and the value of K (generally different manufacturers will have different The value of k is mainly caused by the difference in the process level and material formula of the lithium battery produced by the battery manufacturer), and the approximate capacity of the lithium battery can be quickly estimated.
The above is the method of lithium battery capacity test compiled by Benwei Battery for your reference.
