Planning For Replacement UPS Batteries

The batteries within an uninterruptible power supply are a consumable item and will require replacement during the working life of a UPS system. The standard battery used is a sealed lead acid (SLA) maintenance free battery with a design life of either five years or ten years. The actually working life of these battery design types is typically 3-4 years or 7-8 years respectively.

UPS systems to tend to incorporate advanced algorithms to test their batteries on a regular basis (typically ever 24 hours) and compare results to identify a failing battery set. Without a separate individual battery monitoring system or one-off testing by a service engineer during a UPS preventative maintenance visit with a hand-held battery tester, it is generally impossible to identify a single failing or failed battery. Visual inspections can however identify problems as a failing battery may have a buckled casing (due to heat discharge and high internal resistance) and white electrolyte residue around its terminals.

When it comes to replacing UPS batteries, it is important to match the battery Ah and DC voltage to maintain battery string and runtime characteristics. If a longer or shorter runtime is required, the battery Ah can be adjusted up or down but the number of replacement cells will remain the same. When the battery set is replaced it may be a requirement of the replacement battery service to adjust parameters within the UPS system itself and for this reason it is important to use a certified UPS service partner for the specific UPS brand and system in place.

It is also important to note that lead acid batteries provide a DC electrical supply as a result of a chemical interaction between the hydrochloric acid and the lead plates within them. The typical design life is described as above as say 5 years but this is temperature dependent with the ideal operating ambient being within 20-25 degrees centigrade and the number of complete charge/discharge cycles running from 300-400.

Due to this chemical reaction the entire performance of a battery set will degrade to the performance level of the weakest battery. This is why an entire set has to be replaced if a battery is seen to be failing. Simply replacing a battery blocks does not improve matters within an aging battery string. The new blocks simply degrade quickly in performance to the level that can be offered by the existing battery blocks.

When batteries are replaced a UPS system will either have to be taken off-line or isolated using a maintenance bypass. This may be external to the UPS or an internal bypass arrangement. The battery set itself will be isolated through a battery isolator breaker or at worst case a fuse arrangement.

How long it takes to replace UPS batteries is very much dependent up on the size of the battery set. A large battery block replacement of say 40 blocks of 110Ah can take up to a day. It is not just the number required but the weight of the batteries themselves and access when replacing them. The greater the number of replacement UPS batteries required and their Ah and therefore Kg weight size, the longer it will take and it may even require a two-person team. Once the replacement UPS batteries are installed, the UPS service company should provide a full removal and recycling service for the failed batteries.

At EcoPowerSupplies we provide highly competitive replacement UPS batteries and the necessary battery services required to help keep your power systems running.

Recycling Lead Acid Batteries

We also use dispose and recycle batteries to provide an environmentally friendly service and allow materials within the batteries to be reclaimed. This short video describes how lead acid batteries are recycled into their constituent components.

For more information on our replacement UPS batteries service please contact us.