Previously, the charging head network introduced the self-developed brand Wowaf low-temperature battery cell and Saifude small type battery cell independently developed by Shenzhen Genju Technology Co., Ltd. (hereinafter referred to as "Genju Company"), which have played a good performance through actual measurement.
This time, the charging head network will bring you the Wowaf 18650 30ML battery cell evaluation, its nominal capacity is 3000mAh, the nominal voltage is 3.6V, it has also undergone a variety of safety standards, as well as high safety structure design, accurate power off, pressure relief device;
Appearance introduction
Let's take a look at the appearance and specifications of this battery cell first.
The 18650 30ML battery cell is a cylindrical design with a gray core sleeve color, and the color of the sleeve film can be adjusted according to the requirements to meet the diverse needs of customers.
Wowaf 18650 30ML battery cell has cell coding on the other side:
"WWF 18650 30ML and factory no. "
Rated capacity: [email protected];
Nominal voltage: 3.6V, nominal energy: 10.8Wh;
AC internal resistance: ≤35mΩ.
The contact surface of the negative electrode of Wovaf 18650 30ML battery cell is made of alloy metal and anodized by anodizing process, which is durable and anti-corrosion.
The contact surface of the positive electrode of the Vovaf 18650 30ML cell is still made of alloy, and the disc is also connected with five solder joints.
Using plastic calipers, the cylindrical height of the Vovaf 18650 30ML cell is about 65mm.
Using plastic calipers, the cylinder diameter of the Vovaf 18650 30ML cell is about 18.1mm.
The Wowaf 18650 30ML battery cell weighs about 45.6g.
The Vowaf 18650 30ML battery cell is relatively small in the hands of an adult man.
Charge and discharge test
After looking at the appearance, let's get to the point, and the following will be charged and discharged at 0.2C, 0.5C and 1C rates.
Charge test
The charging test will perform constant current and constant voltage charging at 0.2C, 0.5C and 1C rates, and calculate the total time consumption.
0.2C charging
Draw a line chart, set the current to 600mA, 0.2C to charge the Wovaf 18650 30ML battery, the charging cut-off voltage is 4.2V, and it takes 5 hours and 30 minutes.
0.5C charging
Draw a line chart, set the current to 1500mA, 0.5C to charge the Wovaf 18650 30ML battery, the charging cut-off voltage is 4.2V, and it takes 2 hours and 52 minutes.
1C charging
Draw a line chart, set the current to 3000mA, 1C to charge the Wovaf 18650 30ML cell, the charging cut-off voltage is 4.2V, and it takes 2 hours and 4 minutes.
In the charging test, it took 5 hours and 30 minutes to fully charge 0.2C, 2 hours and 52 minutes to fully charge 0.5C, and 2 hours and 04 minutes to fully charge 1C.
Discharge test
In the discharge test stage, a constant current discharge will be used to calculate the total time consumed, as well as the discharge capacity and energy values.
0.2C discharge
Draw a line chart, set the current to 600mA, 0.2C is the discharge of Wovaf 18650 30ML cells, the average voltage is 3.63V, and the cut-off voltage is 2.5V, which takes about 4 hours and 50 minutes, and the discharge capacity is 2903mAh and the energy is 10.53Wh.
0.5C discharge
Draw a line chart, set the current to 1500mA, 0.5C for the discharge of Wovaf 18650 30ML cells, the average voltage is 3.57V, and the cut-off voltage is 2.5V, which takes about 1 hour and 55 minutes, with a discharge capacity of 2877mAh and an energy of 10.27Wh.
1C discharge
Draw a line chart, set the current to 3000mA, 1C is the discharge of Wowaf 18650 30ML cells, the average voltage is 3.51V, and the cut-off voltage is 2.5V, which takes about 57 minutes, and the discharge capacity is 2859mAh, and the energy is 10Wh.
Summarizing the test data into a table, it can be seen that the battery cell is tested at three magnifications, and the shortest discharge time is 1C discharge, and the discharge time is about 57 minutes. The longest discharge time is 0.2C discharge, and the discharge time is about 4 hours and 50 minutes.
The test data is summarized into a histogram, the overall discharge energy in the discharge test is between 10-10.53Wh, the overall gap is not large, the highest discharge energy is 0.2C discharge gear, the discharge energy reaches 10.53Wh, close to the rated capacity, the lowest discharge energy is 1C discharge gear, discharge energy is 10Wh.
Let's take a look at the difference in the capacity of each gear, draw the data into a curve graph, and you can see that the discharge capacity of the 0.2C discharge gear is 2903mAh, which is close to the rated capacity, and the lowest discharge capacity is the 1C discharge gear with a discharge capacity of 2859mAh.
Internal resistance test
In the internal resistance test part, the charging head network will use the internal resistance test instrument to test the full power internal resistance and empty power internal resistance respectively.
The test data is summarized in the table, and it can be seen that the internal resistance voltage of the full charge is 4.2V, the air internal resistance voltage is 2.5V, and the nominal internal resistance of the Vovaf 18650 30ML cell is ≤35mΩ.
Drawing a histogram, you can see that the internal resistance of 4.2V is 26.56mΩ and the internal resistance of 2.5V is 25.81mΩ, and the internal resistance of full charge and air power does not change much, and does not exceed the nominal internal resistance, which is excellent.
Temperature test
In the temperature test part, the charging head network will measure the temperature of each charge and discharge rate after 30 minutes.
Charging temperature test
0.2C charging
The Vovaf 18650 30ML battery cells are charged at a rate of 0.2C for 30 minutes, and the maximum surface temperature is about 27.8°C.
0.5C charging
Charge the VOWAF 18650 30ML battery cells at a rate of 0.5C for 30 minutes, and the maximum surface temperature is about 28.5°C.
1C charging
The Wowaf 18650 30ML battery cells were charged at a rate of 1C for 30 minutes, and the maximum surface temperature was about 32.7°C.
Discharge temperature test
0.2C discharge
The VOWAF 18650 30ML battery cells were discharged at a rate of 0.2C for 30 minutes, and the maximum surface temperature was about 27.4°C.
0.5C discharge
The VOWAF 18650 30ML battery cells were discharged at a rate of 0.5C for 30 minutes, and the maximum surface temperature was about 28.2°C.
1C discharge
The Wowaf 18650 30ML battery cells were discharged at a rate of 1C for 30 minutes, and the maximum surface temperature was about 34.8°C.
Summary of the charging head network
This Wolaf 18650 30ML battery, the charging head network is tested at 0.2C, 0.5C and 1C three rates, charging, 1C rate charging can be completed in 2 hours 04 minutes, discharge part, you can see that 0.2C rate discharge capacity 2903mAh, close to the nominal capacity, also emitted energy 10.53Wh.
Let's take a look at the internal resistance and temperature performance, the internal resistance values in the empty power and full power state do not exceed the nominal internal resistance, and are around 25-26mΩ, and the internal resistance in the two different states does not change much, in terms of temperature, in three groups of different rates of charge and discharge for 30 minutes after the test temperature, the charging temperature is in the range of 27-33 °C, the discharge temperature is in the range of 27-35, the overall temperature rise is low; The 30ML battery cell, whether it is charge and discharge capacity, internal resistance and temperature performance, has played an excellent performance, effectively solves the problem for extremely cold areas, can discharge normally in a low temperature environment and has passed a variety of safety standards, as well as high safety structure design, further improve safety performance while performance does not decay.
Related Reading:
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2. Low temperature resistance, large capacity, Genju Technology Co., Ltd. launched Wovaf 18650 26ML battery cell
3. Specially prepared for severe cold areas, Genju Technology launched Wowaf 18500 20DBL cryogenic cells