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Do Generators Need Batteries?

Anyone who is new to diesel generators might scratch their head when they first see one and wonder, “Why does an electrical generator need a battery?” But the answer is very simple: to provide the generator with enough start-up power to turn on during a facility-wide power outage. Then, once it’s up and running, the generator will create its’ own electrical power to provide electricity to connected systems and components.

In addition to start-up power, generator systems may draw on battery power to provide:

  • Digital Control Panel operation.
  • DC current for small motors or devices that require DC current.
  • Redundant battery power for the primary battery or genset.

Battery Failures Are The Most Common Reason For Generator Failure

Batteries are the standard lead acid battery – either conventional or maintenance-free. The size of the battery depends on the size of the generator and what components the battery needs to power and sizing is important to proper operation.

Batteries are so important to generator operation that the battery is often the first thing a service technician will check when a generator fails. Because of this, maintaining your battery is an essential part of generator operation. Maintenance may vary depending on whether the battery is conventional or maintenance-free, but in general, maintenance consists of:

  • Ensuring a trickle charge is available to the battery at all times.
  • Testing of the battery at regular intervals.
  • Performing a load test as recommended by the manufacturer.

With proper maintenance, a good quality battery can last 3-5 years, depending on use.

Factors To Consider When Choosing A Generator Battery

Batteries are arguably the most critical, but underrated, subsystem in a diesel genset. Without a battery, or a bank of batteries in the case of parallel gensets, your backup power source may not even turn on, much less provide the electricity you need at critical times. Choose the right battery by:

  • Ensuring the battery is suitable for the application. Consider ambient air temperatures, generator power demands, and manufacturer recommendations.
  • Comparing the currently installed battery against the manufacturer specs. Installed batteries that exceed manufacturer speciRcations are acceptable.
  • Considering the battery manufacturer’s stated lifespan of the battery, the cost vs. performance of the battery, and the warranty.
  • Availability of the battery in your area.

Need Advice On Generator Batteries? Contact Critical Power Products & Services

If you are not sure what type of size of battery you need, contact Critical Power Products & Services for advice. We carry all of the major diesel generator brands and can help you choose the best battery for your generator.

Contact us at 855-968-0176 or send us a question online.

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