Main Causes of Shortened Battery Lifespan in Base Stations

1. The Role of Battery Packs in Communication Systems

Currently, the majority of communication power systems use advanced valve-regulated sealed lead-acid (VRLA) batteries. These batteries typically have a single-cell voltage of 2V and are connected in series to form 48V or 24V systems. The primary functions of these batteries are to protect communication equipment and ensure the smooth operation of the network. In terms of equipment protection, the batteries, together with uninterruptible power supplies (UPS) and switch power supply systems, play a vital role in preventing voltage surges, spikes, and transients from the electric grid, effectively protecting communication devices and preventing site outages. Regarding network operation, the batteries, together with UPS and switch power supply systems, maintain system operation during power interruptions and filter out noise voltage, ensuring communication quality.

Once installed in communication base stations, these batteries typically do not require replacement for several years. Therefore, it is crucial to enhance battery maintenance to improve its operational conditions, which in turn can effectively extend the battery's lifespan. Online battery monitoring plays an indispensable role in the maintenance of communication power systems, especially in unmanned settings.

2. Current State of Battery Technology in Communication Systems

Battery packs are a crucial part of the base station's DC uninterruptible power supply, with investments comparable to those in switch power supply equipment. Most mobile base stations use valve-regulated sealed lead-acid (VRLA) batteries developed in the late 20th century. Due to their valve-regulated sealed structure, these batteries do not require acid or water maintenance, are free of acid leakage or mist, and can be installed alongside equipment in the same room. They are popular due to their compact size, light weight, low self-discharge, minimal maintenance, long lifespan, convenience, and reliability. However, it's important to note that while the electrochemical principles of VRLA batteries remain unchanged, the increasing demands for battery performance have made their maintenance more stringent. Additionally, early on, manufacturers sometimes referred to these batteries as "maintenance-free," leading some maintenance personnel to believe that the batteries required no upkeep. This misconception has had a lasting impact, resulting in insufficient attention to battery maintenance and testing.

From the current usage of base station batteries, the most common issues are rapid capacity loss, short lifespan, and frequent site outages. Battery quality from major VRLA manufacturers generally meets operator requirements, though there are differences in quality and performance among manufacturers. However, battery quality itself is not the main reason for the rapid capacity loss and shortened lifespan. Considering the battery structure, performance, and on-site conditions, it is evident that under normal circumstances, VRLA batteries should last 1-4 years without a significant drop in capacity. The primary factors affecting battery lifespan are related to the operating environment and maintenance practices at base stations.

Main Causes of Rapid Capacity Loss and Shortened Lifespan in Base Station Batteries:

Frequent Power Outages and Long, Irregular Power Cut Times: The frequent charging and discharging of batteries due to power outages can lead to the early failure of the battery. A common issue is the sulfation of the negative plates, which is a typical sign of early capacity loss. If a base station experiences frequent power cuts, the battery discharges before it is fully recharged, leading to undercharging. Repeated undercharging results in cumulative capacity loss, causing the battery’s capacity to drop significantly in a short time and shortening its lifespan.

Improper Switch Power Supply Settings: If the voltage settings for undervoltage protection and reset voltage for the base station’s switch power supply are too low, the battery can experience over-discharge or deep discharge, which accelerates sulfation of the negative plates. Proper undervoltage protection values must be set based on load current. Currently, undervoltage protection is often set too low, leading to over-discharge, and when the battery is repeatedly over-discharged and not fully recharged, its lifespan is greatly shortened.

Harsh Operating Environment: After power outages, if the base station does not have air conditioning, the internal temperature rises, reducing the battery's lifespan. If the air conditioning system is faulty and not repaired in time, or if power outages prevent the AC from working, temperatures in the station can exceed 70°C, which severely impacts battery performance. High temperatures accelerate thermal runaway, causing corrosion of the positive plates, plate deformation, and battery swelling or cracking, ultimately leading to a rapid decrease in battery capacity and shortened lifespan.

Failure to Recharge After Discharge: In some remote areas, power outages are frequent and last for extended periods. If the battery discharges to its termination voltage and is not recharged in a timely manner, the battery’s capacity decreases, and its lifespan is shortened. Similarly, if the switch power supply’s floating charge voltage is too low, the battery may remain in an undercharged state for long periods.

3. The Necessity of Battery Monitoring

As previously discussed, the communication power system is the backbone of the communication network, and the backup battery is the final line of defense. Once an accident occurs due to battery failure in the communication equipment room, the consequences can be catastrophic. To ensure the smooth operation of communication networks, operators are increasingly focusing on battery maintenance and testing. They have adopted strict maintenance standards, such as IEEE1189-2005, and now rely on more effective monitoring systems.

Traditional maintenance methods, such as periodic discharge testing, have limitations due to personnel constraints, remote locations, and long testing times. Battery monitoring systems offer several advantages over traditional methods:

Reduced manual labor for on-site measurement and battery inspection.

Continuous battery health status monitoring without the need for periodic visits, saving costs.

Enhanced reliability of power supply, reducing system downtime.

Early replacement of failing batteries before they affect other cells, thereby extending the overall battery system's lifespan.

Better management of battery replacement cycles, ensuring proactive procurement and reducing the need for bulk replacements.

Improved customer satisfaction by minimizing power interruptions.

Enhanced system reliability and production capacity by identifying failing batteries early.

Utilizing patented impedance measurement technology to detect battery issues at the earliest stages.

Remote monitoring and trend analysis, improving management efficiency.

Accurate tracking of battery performance during power failures, improving operational planning and readiness.

Although implementing battery monitoring systems increases operational costs in the short term, the long-term benefits—such as extending battery life by 30%, reducing maintenance workload by 75%, and lowering maintenance costs by 80%—make it a worthwhile investment. It also reduces site outages, improving communication reliability and customer satisfaction.