Everyone is talking about batteries today. They are becoming an increasingly important component in the transition to a greener world. Electric cars, energy storage, telecommunication and of course, data centers. They all need batteries in one way or another.

Despite all of this most people don’t know very much about what goes on inside a battery and how to get the best from it. Batteries are sometimes one of the last elements to be considered. But good forward planning of the battery and its environment will help to ensure reliability and long life of the asset.

This article provides a few guidelines that should be considered when planning a data center and its backup power system.

A battery backup system must operate for many years and be ready for instantaneous release of energy. A battery is a component of the overall system. Most data centers use auxiliary gensets. The problem is that they need a time interval to reach full power. This is where batteries come in and play the role of instant power.

When choosing a battering system, the following are some of the critical elements that need to be considered.

Plan for battery performance at the end of their specified life

A battery is a device that converts chemical energy into electrical energy. The reaction involves the transfer of electrons from one material to another. This is called an anode and a cathode, and the transfer is carried out usually by a material known as an electrolyte. This transfer of energy is known as a charge or discharge. A discharge and recharging of the battery cell is a cycle.

All batteries, due to the characteristics of the chemistry, are subject to loss of performance over time. This is called ageing. This ageing factor must be considered when designing and specifying a system since a battery needs to be able to support the design load of the system over life. For example, a battery system, designed for 10 years’ service, must be able to support the load at the end of its 10 years’ service.

Consider mains power reliability

Throughout the world power, the quality and consistency of power generated by the utility differs. Some areas may have only a few power outages a year, and last just a few moments, while others are frequent and last for a long period. The implications of this for a battery are considerable.

Frequent power outages will have heavy demands on the system and consequently the battery and genset, which raises the question of cycle life. Frequent power outages and for long duration can mean that the system has to be able to withstand many cycles, many of which may not be full discharges. This can subject a battery to heavy workload and partial charges and the need to recharge the system rapidly.

Temperature plays a major role in battery life and performance

Temperature plays an important role in the life of a battery. In general, high temperatures lower the life of a battery as they speed up the internal chemical reaction. This applies to all chemical batteries. At lower temperatures, usually below zero, the performance of a battery is impeded. Most of us have experienced this with starting a vehicle in freezing conditions.

When planning an installation, it is important to consider where batteries will be situated and how to maintain and monitor the environment of the room. A battery room with variable temperatures will affect the life of a battery system.

Even a few degrees of higher temperatures, but over several years will shorten the operating life of the battery. It therefore makes for good design planning to consider the room where the batteries will be situated.

System redundancy: A duplicated battery requirement may be different

Batteries, as stated at the beginning of this article, are components of a system. This is often overlooked. Data centers, including batteries, all plan for redundancy. This means that every system is replicated, and often in very different locations.

So, when planning a battery system for a new installation, it is not enough to duplicate the installation. The environmental factors such as layout, power and operating temperature may be different.

A good installation solution must take these factors into consideration. It is important to consider that a second battery installation for a data center may have different environmental as well as operating needs. Therefore, each room needs to be considered individually.

Plan a service routine procedure

Many batteries today are classified as ‘maintenance-free’. These batteries are designed with an electrolyte sealed inside the battery; previously the electrolyte needed to be periodically ‘topped-up’ as well as a general maintenance inspection. This does not mean that the batteries can be ignored over their specified life.

In the latest Uptime Institute global data center survey which identifies major incidents and issues in the industry, one of the areas highlighted ‒ but not the first ‒ was batteries. They identified that most battery failures were due to lack of routine maintenance. But what does this mean?

Batteries often exist in a separate location on a site. The system is installed with a charger and specified for a period of guaranteed operation at specified operating conditions.

Maintenance free batteries do not need a high level of maintenance, but they do need periodic inspections and checks to ensure that all batteries are performing.

A large battery system can consist of hundreds of individual batteries, all linked together. The poor performance of one or more batteries can damage the system. A routine inspection of the battery system does not take much but it should be done as part of the operational routines of any data center.

Routine service can avoid future problems. Most battery suppliers, such as FIAMM Energy Technology, offer a monitoring solution that checks voltage and temperature and can act as an advanced warning system for problems.

The checklist:

• System life: Plan for performance needs at the end life
• Temperature: Temperature beyond the design will reduce life
• Power quality: Frequent power outages mean more demand on the battery
• Service routine: Develop a service inspection routine, it will help to avoid problems
• Design life: Remember the life of any chemical battery is affected by its operating environment
• Replace batteries at the end of life: Don’t wait for a performance failure
• Environment: Choose a battery system that is good for the environment.

For more information, visit the FIAMM website here.