Battery capacity test

　　Capacity test of battery

　　 When conducting periodic capacity test on battery, you can choose the following capacity test methods.

　　1: On-line measurement method

　　 (1) In the DC power supply system, adjust the UPS output voltage to the protection voltage, and the battery To supply power to the actual load, find the battery with the lowest voltage and the worst capacity in the battery pack as the object of capacity test during discharge.

　　 (2) Turn on the UPS to charge the battery pack, and wait for the battery pack to be fully charged and stable for more than 1 hour.

　　(3) Perform a 10-hour rate discharge test on the battery that was found to be the worst during discharge in (1). Measure and record the terminal voltage, temperature, discharge time and room temperature of the battery before and after discharge. Afterwards, measure and record once every 1h. When the discharge is almost to the end voltage, it should be measured and recorded at any time in order to accurately record the discharge time.

　　(4) The discharge current multiplied by the discharge time is the capacity of the battery pack. If the room temperature is not 25°C, it should be converted to the capacity at 25°C according to formula (1). How to maintain the battery capacity depends on the basic steps of communication battery battery online capacity maintenance here.

　　(5) After the discharge test, use a charger to recharge the battery to restore its capacity.

　　(6) Draw a discharge curve based on the measurement record data.

　　2: Check discharge test method

　　 In order to be able to grasp the approximate capacity of the battery pack at any time, conduct a check discharge test It is necessary, and the method is:

　　 (1) In the DC power supply system, adjust the UPS output voltage to the protection voltage, and the battery supplies power to the actual load. Before and after the battery pack is discharged, the terminal voltage, temperature, room temperature and discharge time of each battery shall be measured and recorded. Discharge up to 30% to 40% of the rated capacity.

　　 (2) After the discharge is over, the battery should be charged, and the charged power is 1.2 times the discharged power.

　　 (3) Draw a discharge curve based on the data recorded in the measurement, and save it for comparison when measuring again later.

　　 3: Offline measurement method (when conditions permit)

　　 (1) Fully charge the battery pack After leaving the UPS, let it stand for 1 hour, and connect an external (intelligent) dummy load under the condition of an ambient temperature of 25℃±5℃, and use a 10-hour discharge rate for the discharge test.

　　 (2) The terminal voltage, ambient temperature and time of the battery should be measured before the discharge starts.

　　(3) During discharge, the terminal voltage, discharge current, and indoor temperature of the battery should be measured and recorded. The measurement interval is 1h, and the discharge current fluctuation shall not exceed 1% of the specified value.

　　(4) During discharge, the terminal voltage and room temperature of the battery should be measured and recorded, and the measurement interval is 1h. Measure at any time at the end of the discharge period in order to accurately determine the time to reach the discharge termination voltage.

　　(5) The discharge current multiplied by the discharge time is the capacity of the battery pack. When the battery is discharged at a rate of 10 hours, if the temperature is not 25°C, the actual measured capacity should be converted into the capacity at 25°C according to the following formula Ce:

　　Ceu003d Cr/[1+K(t-25℃)](1)

　　 where: t—ambient temperature during discharge

　　K—Temperature Coefficient (Ku003d0.006/℃ when discharging at a rate of 10 hours;

　　 When discharging at a rate of 3 hours, Ku003d0.008/℃; 1 hour rate When discharging, Ku003d0.01/℃)

　　(6) After discharging, the battery pack should be charged, and the charged power is more than 1.2 times the discharged power.

　　 Battery description:

　　(1) For the battery pack of UPS power supply system, offline measurement method is not recommended Capacity test.

　　(2) When performing on-line measurement method and check capacity test, for UPS equipment with battery discharge test function, it is necessary to turn on the battery discharge detection function to discharge the battery test. For UPS without this function, it is necessary to turn off its AC input power and conduct a discharge test.

　　Battery precautions

　　(1) It is very important to ensure the system operation during the capacity test. During the test, you should know in advance whether there is a planned blackout of the mains power supply, and the backup generator set should be in good condition. How to extend the battery life, please see the six measures to extend the battery life.

　　 (2) Before the battery capacity discharge test, a multimeter, internal resistance meter, and conductivity meter are used to conduct a preventive test on the performance of the battery.

　　 (3) In order to ensure the accuracy of the capacity test, a professional battery capacity online test instrument and a dummy load should be used for testing.

　　Contact: Power Kingdom