High rate battery life testing, high rate battery quality testing method. High magnification batteries are widely used in high-tech products, such as aircraft model drones, intelligent robots, military products, etc. Therefore, high magnification batteries are also a type of product that requires high quality and safety. However, many consumers are often unclear about the performance and testing methods of batteries when using them. The service life of high-quality batteries is about two to three years, and the non durable performance of high rate batteries is their fast power consumption and reduced charging time. In order to ensure the safe use of high rate batteries, we should take good care of battery protection.
Testing methods for the lifespan of high rate batteries
High rate battery life testing is mainly to test the charging and discharging times of lithium batteries when their available capacity drops to the allowable value. The specific detection steps are as follows:
1. High rate batteries are discharged at a constant current of 0.2C to the specified termination voltage (usually 3.0V) at an ambient temperature of (20 ± 5) ℃, then charged at a constant current of 0.2C to the termination voltage (usually 4.2V), and switched to constant voltage charging (charging termination current is generally 0.02C);
2. High rate batteries are discharged at a constant current of 0.2C to the specified discharge termination voltage at an ambient temperature of (20 ± 5) ℃;
3. High rate batteries are cycled at an ambient temperature of (20 ± 5) ℃, and the battery is left idle for no more than 1 hour between charging and discharging, or between discharging and charging;
4. High rate batteries should be discharged and charged in cycles according to steps 1 and 2 until the discharge capacity is less than 70% of the rated capacity.
Testing methods for the quality of high rate batteries
1. The fastest method for detecting the quality of high rate batteries is to test the internal resistance and maximum discharge current. A high-quality battery has a relatively small internal resistance and a large maximum discharge current. Using a 20A range multimeter and directly short circuiting the two electrodes of a lithium battery, the current should generally be around 10A or even higher, and can be maintained for a period of time. A relatively stable battery is a good one.
2. Appearance inspection. The fullness of the appearance, such as a high magnification battery with a rated capacity, which is bulky, finely crafted, or packaged in a fuller manner.
3. Hardness testing. You can gently or moderately pinch the middle part of the battery with your hand. If the hardness is moderate and there is no soft squeezing sensation, it indicates that the battery cell is of relatively high quality.
4. Weight testing. Remove the outer packaging and feel if the battery weight is relatively heavy. If it is thick, it belongs to high-quality battery cells.
5. During the charging process of a high rate battery, if the two poles of the battery do not heat up after continuous discharge for about 10 minutes, it indicates that the battery protection board system is complete. Generally, batteries with high-quality protection boards have better quality than ordinary batteries.
How to check the quality of the battery protection board?
The main function of the battery protection board is to provide charge and discharge protection for series connected battery packs; When fully charged, it can ensure that the voltage difference between individual batteries is less than the set value (generally ± 20mV), achieving uniform charging of each individual battery in the battery pack, effectively improving the charging effect under series charging mode; Simultaneously detecting the overvoltage, undervoltage, overcurrent, short circuit, and over temperature status of each individual battery in the battery pack to protect and extend the battery's service life; Undervoltage protection prevents each individual battery from being damaged due to over discharge during use.
1. Determine the correct wiring of battery cables through a multimeter;
2. After measuring the voltage to be normal, plug the ribbon cable into the protection board and measure the resistance between protection boards B - and P -. If the resistance is 0, it indicates that they were unobstructed before and the battery protection board is good.
3. The voltage between B - and the total positive electrode of the battery, as well as the voltage between P - and the total positive electrode of the battery, can be measured by connecting the B - line. If the voltage is consistent, it indicates that the protection board is normal, and if the two voltages are consistent, it indicates that the protection board is normal. If P - is discharged through high current, there will be a slight voltage drop and the protective plate will heat up (around 50 degrees), which is a normal phenomenon.
Check whether the high magnification battery meets the specified safety indicators
1. Squeeze vigorously. Place the fully charged tested battery on the testing plane of the testing machine, then apply 13+1KN of extrusion force with an hydraulic cylinder, and finally squeeze the battery with a steel rod with a diameter of 32mm. If the battery can withstand the maximum pressure and there is no explosion or fire, it indicates that the battery product is qualified.
2. Heavy object impact. After fully charging the tested battery, place it on the testing plane of the testing machine, place a steel column with a diameter of 15.8mm vertically in the center of the battery, and freely drop a weight of 9.1kg from a height of 610mm onto the steel column above the battery. If the battery does not ignite or explode, it indicates that it is OK.
3. Overcharge test. The so-called overcharge test is actually to test whether the internal stability of a high rate battery is stable. The method is very simple. First, the battery is fully charged with 1C, and then the overcharge test is carried out according to 3C overcharge with 10V. When the battery overcharges, the voltage rises to a certain voltage and stabilizes for a period of time. When it approaches a certain time, the battery voltage rises rapidly. When it reaches a certain limit, the high cap of the battery is pulled off, and the voltage drops to 0V. If the battery does not explode or catch fire during this process, it indicates that the battery is a qualified product.