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A guide to UPS battery: selection and maintenance
2020-08-24

UPS battery or battery for UPS is so important that it is regarded as the heart of UPS. It not only determines the backup time/run time of your UPS but also serves to make your system more reliable under normal conditions. However, few people will pay attention to it when selecting or using it, as a result, battery accidents happen frequently. According to a report, Battery failures account for more than half of all UPS failures. 


kstar battery series

For users, when choosing a battery, battery technology, price, and product quality should be considered. UPS power supply applications normally use the VRLA type battery because of its safe and lower cost. VRLA stands for Valve-Regulated Lead-Acid and is the designation for low-maintenance lead-acid rechargeable batteries. Because of their construction, VRLA batteries do not require regular addition of water to the cells. VRLA batteries are commonly further classified as Absorbent Glass Mat battery or Gel battery, they are defined as sealed lead-acid batteries, but they are not 100% sealed, they have a safety pressure relief valve.

AGM uninterruptible power supplies batteries are the most popular type because of its lower internal resistance & self-discharge, higher efficiency, faster charge speed and can deliver a high current of short duration.

After selecting a battery with safer technology and famous brands which ensure the high quality. you should know how to install and correctly use it.

Installation & Maintenance of VRLA battery


Because the battery will generate heat or rise to a specific temperature during charging or use, the environment where the battery is located should have good ventilation and heat dissipation capabilities, or be equipped with air conditioning.

Battery should be stayed in the warehouse 5℃~35℃ where it's dry, clean, shade, and avoid sunlight

The battery should be charged properly. Undercharging the batteries may reduce the service life of the battery system and overcharging batteries may create a hazard to your facility or personnel.

At least once per year, it is advised to perform a visual inspection on your batteries. Any swelling or corrosion may indicate an adverse condition that may cause premature failure. When visually inspecting the battery blocks, it is also important to look at the battery cabinet or rack itself. Any leaking electrolyte may be flowing towards the battery rack/cabinet itself. This could result in corrosion or short circuit to the battery rack/cabinet and create a hazard to your critical power and/or personnel.

With proper maintenance, A VRLA battery would last for 8-10 years at 25°C (77°F), would only be good for 5 years if operated at 33°C (92°F).

Lithium-ion battery for UPS

These years, Lithium-ion technology as emerging battery technology has attracted media attention for some time. Compared with VRLA battery, it is greener, 70% smaller and 60% lighter, and can work reliably at higher temperatures. Most importantly, it offers a longer operational life than VRLA, with 12 – 15 years being realistic.

However, it is 2-3 times more expensive than VRLA battery and not as safe as lead-acid batteries This is why it hasn't been completely popular yet.