Precautions for using EPS battery
Precautions for the use of EPS batteries:
In order to keep the available capacity of the battery used in the emergency power supply from decreasing and to keep the charging and discharging characteristics of the battery from significantly deteriorating with time, prolong the service life of the battery pack. In the daily use of emergency equipment, the following should be noted:
(1) Try to avoid over-current charging of the battery in the EPS. Because overcharging is easy to cause the positive and negative electrodes inside the battery to bend and the active material on the surface of the electrode plate to fall off, the consequences of which are less serious will cause the available capacity of the battery to decrease, and the worst will damage the battery
(2 ) Try to avoid short-circuiting or over-discharging the equipment battery. Excessive discharge will cause the sulfation of the surface of the internal plates of the battery, which results in an increase in the internal resistance of the battery. In severe cases, it may even cause reverse polarity of individual batteries and permanent damage to the battery.
(3) Try to avoid over-voltage charging of the equipment battery. Over-voltage charging will often cause the water contained in the electrolyte in the M-type battery to be electrolytically separated into hydrogen and oxygen and overflow, thereby Lead to shortening of battery life.
(4) Try to avoid the equipment battery being idle for a long time or leaving the battery in a floating state for a long time without discharging, because this may cause the internal resistance of the battery in the uninterruptible power supply to exceed its storage life and cause internal resistance to increase Large or permanent damage.
In EPS emergency power supplies, batteries with a rated voltage of 12V are generally used in series to achieve the required rated DC voltage. In a larger power EPS system, in order to achieve the required total battery capacity , It is often necessary to connect multiple groups of batteries in parallel, and battery manufacturers generally do not recommend too many groups (for example, more than 6 groups) of batteries to be used in parallel. The reason is said to be easy to cause circulation and unbalanced charging and discharging. And high-power EPS must use multiple sets of batteries in series and parallel. For this reason, a lot of tests, analyses and observations have been done on batteries of the same brand, specification, and model in series and parallel. The following schemes are effective. Under normal operating conditions, the supplier can be required to make necessary selections for the internal resistance of the battery (control at 2-3%). Then take the necessary current sharing measures from the process: a. Ensure that the length and specifications of the connection of each battery are exactly the same; b. Ensure that the length and specifications of the connection between each battery pack and the EPS host are exactly the same. It uses the inherent resistance of the wire to act as a current-sharing resistance during high-current charging and discharging, so as to achieve automatic balance between battery packs. The main problem of parallel operation should be that the current between the battery packs is difficult to control. For this reason, how to choose the specification and length of the wire is very particular. In addition, power diodes are used to isolate and converge each group of batteries, and multiple chargers are used to charge separately. Such a system will be more reliable and safer. At the same time, before each battery pack is connected in parallel, it should be confirmed that they are all in a fully charged state. But this will increase the cost a lot. No matter what measures are taken, parallel connection of batteries of different brands or models is naturally not advisable.