How to truly understand the performance of a battery?
Personal usage experience?
Let us explain how to properly analyze battery data from the perspective of a battery manufacturer.
The most important data for battery performance are: ① Continuous discharge current, ② Mid-Voltage discharge voltage, ③ Discharged capacity and ④ Smoothness of discharging curve.
1. The size of the sustainable discharge current;
When the battery is fully charged at 4.2v, if it can sustain the same current until it is discharged to 3.0v, and complete about 95% of the capacity discharge, then it is the true sustainable discharge performance. Please pay attention to the two factors that determine this performance: the current size and the actual capacity of the battery that can be discharged by about 95%.
Example: AULINE 850MAH 80C battery, can sustain a discharge of 60C (51A) and instantaneously discharge 80C (68A). When discharged from 4.2v to 3.0v, it can discharge about 94%-95% of the capacity (799MAH-807.5MAH). Only under these two conditions can it be said that the true performance of this battery is "sustainable discharge of 60C".
Example: A certain brand 850MAH 80C battery, labeled as 80C instantaneous 160C, when tested with our continuous discharge of 60C (51A) standard, the actual capacity discharged from 4.2v to 3.0v is only 40-45% of the labeled capacity (340MAH-382.5MAH), which indicates that the battery information is seriously exaggerated and does not match the actual battery information.
2. Discharge median voltage;
This data is an important value for us to judge battery performance. This value refers to the voltage of the battery when the median value is set during the total duration of continuous discharge current. Understanding the discharge median voltage can quickly determine the average discharge power of the battery, which is the discharge median voltage value multiplied by the continuous discharge current equals the average discharge power.
It can effectively help customers choose the battery that suits them.
For example, AULINE 850MAH 80C battery, the continuous discharge time of 60C (51A) is 1 minute and 2 seconds, and the median voltage is 3.3857V. That is, when the battery is tested with a continuous discharge of 60C (51A) for 31 seconds, the voltage of the battery is 3.3857V, and the average discharge power is 3.3857V*51A=172.67wH.
3. Discharge capacity;
Generally, the battery capacity we fill in is the capacity obtained by discharging at a constant current of 1C or 0.5C from 4.2V to 3.0V. For high-rate lithium batteries, the larger the capacity that can be discharged under the test standard conditions, the better the battery performance.
For example, AULINE 850MAH 80C battery can sustain a discharge of 60C (51A) and an instant discharge of 80C (68A). From full charge of 4.2V to 3.0V, it can discharge 94%-95% capacity (799MAH-807.5MAH).
For a certain brand of 850MAH 80C battery, the label shows an instant 160C discharge at 80C. Tested under our continuous discharge of 60C (51A), the actual discharge capacity from 4.2V to 3.0V is only 40-45% of the labeled capacity (340MAH-382.5MAH).
Therefore, under the same capacity and test conditions, the larger the capacity that can be discharged, the better the performance. The closer it is to the information displayed on the label, the better the battery performance without false labeling.
4. Discharge curve;
We use professional battery testing equipment to test the battery, and we will get a discharge curve (a curve in which the battery voltage decreases continuously according to the discharge time). If the discharge curve shows a stable downward trend, it indicates that the battery has stable discharge and excellent discharge performance. If there are spikes or ups and downs, it indicates poor battery discharge performance.
Based on the continuous discharge results of the battery, analyzing the discharge capacity, median voltage, and discharge curve is the most accurate way to judge the actual discharge performance of the battery.
AULINE will continue to upload more real battery test discharge charts and results, allowing customers to better understand the true performance of our products.