Maintenance free battery charging and discharging characteristics

Maintenance-free batteries have self discharge effects. There will be a delay of several months from the production workshop to the user's use. Taking lead-acid batteries as an example, when stored at an ambient temperature of 30 ℃ for 8 months, the residual capacity of the battery is only half of the original capacity. Therefore, for newly purchased batteries that come with UPS, a longer period of charging is generally required, which is called initial charging. The initial charging current of the battery should be charged at 0.1C, and the battery can be recharged after discharge, which is called normal charging. Currently, two charging methods are commonly used in UPS: float charging and pulse charging. The so-called floating charging refers to the parallel operation of the output of the rectifier and the battery, and the simultaneous power supply to the load. In fact, the current provided by the rectifier is divided into two paths, one to the load and the other to the battery, to supplement the internal losses of the battery. The floating charging working method is simple to connect, which is beneficial for improving the transient response characteristics of UPS output. The characteristic of pulse charging is that the charging current varies with the capacity of the battery. Charging in this way can shorten the charging time.

1. Charging voltage

Due to the fact that UPS batteries are in a backup mode of operation, they are in a charging state under normal mains conditions and only discharge when there is a power outage. To extend the service life of the battery, UPS chargers are generally controlled by constant voltage and current limiting, and the battery switches to float charging state when fully charged.

For batteries with a terminal voltage of 12V, the normal float charging voltage is between 13.5 and 13.8V. If the float charging voltage is too low, the battery will not be fully charged, and if the float charging voltage is too high, it will cause overvoltage charging. When the float charging voltage exceeds 14V, it is considered as overvoltage charging. Overvoltage charging of battery packs is strictly prohibited, as it can cause the water contained in the electrolyte in the battery to be electrolyzed into hydrogen and oxygen, leading to an increase in electrolyte concentration, shortened battery life, and even damage.

2. Charging current

The charging current of a battery is generally expressed in C, and the actual value of C is related to the battery capacity. For example, if it is a 100Ah battery: C is 100A. The optimal charging current for lead-acid maintenance free batteries is around 0.1C, and the charging current must not exceed 0.3C. Excessive or insufficient charging current can affect the service life of the battery.

The ideal charging current should adopt a phased constant current charging method, which means using a larger current in the early stage of charging, changing to a smaller current after a certain period of charging, and using a smaller current at the end of charging. The design of charging current is generally 0.1C, and when the charging current exceeds 0.3C, it can be considered as overcurrent charging. Avoid using a fast charger for charging, as it may cause the battery to be in a state of "instantaneous overcurrent charging" and "instantaneous overvoltage charging", resulting in a decrease in the battery's available power and even damage to the battery. Overcurrent charging can cause the battery plates to bend and the active substances to fall off, resulting in a decrease in the battery's power supply capacity. In severe cases, it can damage the battery.

Product features

(1) Long service life

High strength tight assembly technology improves the tightness of battery assembly, prevents the detachment of live materials, and improves the service life of batteries.

Low acid specific gravity electrolyte improves battery charging acceptance and enhances battery deep discharge cycling ability.

Increase the acidity design to ensure that the battery does not shorten its service life due to electrolyte depletion.

Therefore, the normal float charging design life of maintenance free series batteries can reach over 15 years (25 ℃)

(2) Excellent high rate discharge performance

High intensity tight assembly process, extremely low internal resistance of the battery, excellent high current discharge characteristics, increased by more than 20% compared to ordinary batteries.

(3) Low self discharge

High purity raw materials and special manufacturing processes, with minimal self discharge, can be stored at room temperature for more than half a year without the need for additional electricity.

(4) Easy maintenance

The special oxygen absorption cycle design overcomes the phenomenon of electrolytic dehydration during the charging process of the battery. The water content of the electrolyte remains almost unchanged during use, so the battery does not need to be replenished with water during use and is easy to maintain.

(5) High security

The battery is equipped with special safety measures inside.

(6) Easy to install

The battery can be installed vertically, horizontally, or in layers, with a small footprint and flexible and convenient installation.

(7) Clean and environmentally friendly