1. Measurement of float voltage method
The setting of float voltage has a significant impact on the lifespan of batteries. In theory, it is required that the current generated by the float charging voltage is to compensate for the self discharge of the battery. Excessive float charging voltage can cause corrosion and dehydration of the positive electrode of the battery, resulting in a decrease in battery capacity. However, if the float charging voltage is too low, it can also lead to insufficient charging of the battery, causing it to lag behind, and in severe cases, electrode sulfation may occur. The selection of float charging voltage can be set according to the requirements of the manufacturer's manual.
Although measuring the float voltage and making timely adjustments is an important task in the daily maintenance of batteries, measuring the float voltage alone cannot identify outdated individual batteries.
2. Internal resistance testing method
There is a certain fixed relationship between the remaining capacity of a battery and its internal resistance, especially when the remaining capacity is less than 50%, it will rapidly decrease. Therefore, there is good consistency in judging the battery capacity based on the conductivity or resistance value of the battery.
3. Capacity measurement method
To accurately know the health status of VRLA batteries, only capacity tests can be conducted on the batteries. However, traditional offline capacity testing methods require the battery to be detached from the system, which poses various security risks. Another online measurement method, although it solves this problem, also has inconvenient factors for on-site rapid testing and judgment due to the long testing time.