Getting to Know Your UPS Batteries: VRLA

Now that we have a better idea of our UPS battery options from our previous article, we can take a look at these options individually in more depth. We will start with the most popular option currently, the VRLA UPS battery.

VRLA, or Valve Regulated Lead Acid UPS batteries, are also sometimes called “maintenance free” batteries. This term is a misnomer, as VRLA batteries still require cleaning and regular functional testing. The term “maintenance free” comes from the fact that you are not able to add fluid to the battery. The term “valve regulated “means these batteries limit the inflow and outflow of gas to the cell.

In a standard UPS configuration, VRLA batteries are typically set up in internal or external strings that can range from 1 to 40 batteries, depending on the application they are being used for. You may also see either single or multiple strings running in parallel to each other.

VRLA batteries are the most popular UPS battery type currently. Why the popularity? There are four easy reasons:

• Cost– They are typically reasonably priced. They are frequently less expensive than Wet Cell batteries, and they are also easier to work with, given some of the environmental hazards that need to be accounted for with Wet Cell batteries, such as a separate storage area and possibly hydrogen detection or exhaust requirements. VRLA batteries are usually part of UPS package or turnkey pricing. A standard cost VRLA battery will usually provide a life of 4 to 5 years for that battery.
• Availability– VRLA batteries are highly available on the market today from a wide range of manufacturers.
• Safety– VRLA batteries contain lower levels of hazardous gases than do Wet Cell batteries. Hydrogen gas can be formed when a battery is being charged, and Wet Cell batteries also contain sulfuric acid in the battery fluid.
• Low maintenance– Although this battery is not totally “maintenance free,” they require much less maintenance than a Wet Cell battery does. They do need to be monitored and tested per IEEE standards. They typically only need scheduled maintenance every 6 months. VRLA batteries do not require equalize imaging, gravity readings, or water level checks. VRLA maintenance should cover the following:
  • Thermal readings
  • Checking connections
  • Checking battery for oxidation and bulging
  • Internal resistance and voltage testing

While VRLA batteries have a lot of support currently, it is worth noting that they also have common problems. HEAT is very BAD for these batteries, and they should not be positioned near any heat source within their environment. The ideal temperature for these batteries is to be stored at 77 degrees or lower in a dry area. For every 15 degrees Fahrenheit over 77, a VRLA battery’s life is cut in HALF.  The Institute of Electrical and Electronic Engineers (IEEE) states in their 2017 National Electrical Safety Code ® that storing VRLA batteries in a temperature controlled environment is essential.

If VRLA battery environments are neglected and become overheated, this can lead to catastrophic issues such as thermal runway. Thermal Runway is defined as a kind of uncontrolled positive feedback situation, where an increase in temperature changes the conditions in a way that causes them to further increase temperature. This can lead to battery explosions or battery meltdowns, and may cause huge monetary losses.

Making decisions on what type of batteries to use in an environment is heavily dependent on how the environment is set up, your critical load requirements and the level of training you and your staff have with UPS batteries and UPS management. QPS and our highly trained staff are happy to help you evaluate the most effective and safest battery option for your location. Contact QPS today to schedule your battery evaluation.