How to distinguish between good and bad UPS batteries

How to judge the quality of UPS battery

There is a dedicated battery measuring instrument to judge the quality of the battery, but the average user rarely has this kind of instrument, and there is only a multimeter.

The following points are summarized for judging whether the battery is good or bad in the maintenance, for reference. 　

1. Judging from the appearance, observe whether the appearance is deformed, protruding, leaking, or ruptured. Explosion, scorching, whether there is oxide seepage at the screw connection, etc.

2. If there is no abnormal appearance in the load measurement, the UPS works in battery mode with a certain amount of load. If the discharge time is significantly shorter than the normal discharge time, it will not return to normal after 8 hours of charging. Standby time, determine battery aging.

3. Measure with a multimeter

A. Measure the voltage of each battery in the battery pack in the battery discharge mode, if one or more of the battery terminals are significantly higher or lower than the voltage Nominal voltage (nominal voltage 12V/cell), to judge battery aging.　

B. Measure the charging voltage of each battery terminal in the battery pack in the mains mode. If the charging voltage of one or more of the batteries is significantly higher or lower than other voltages, the battery is judged to be aging.

C. Test the total voltage of the battery pack The total voltage of the battery pack is obviously lower than the nominal value (take the nominal value of the C1K battery pack as 36V as an example), and it cannot return to the normal value after 8 hours of charging. Even if it returns to the normal value, the discharge time does not reach the normal discharge time, and the battery is judged to be aging. D. Measure when the battery is turned on. The UPS is not turned on or connected to the mains. Use a multimeter to measure the total voltage of the battery pack. Take C1K as an example. At this time, the voltage may be between 36V-40V, which is a normal value. Hold the instructions of the multimeter, and then turn on the power button. If the total battery voltage drops below 30V or even more than ten volts at this time, the UPS will automatically shut down immediately, and the voltage will immediately return to the original value after shutting down. Determine the battery aging.