A range of energy storage technologies are available today. They are designed to save previously generated energy and deploy or use it at a later time. The predominant technology for energy storage employed by utilities and corporations is lithium-ion batteries.

What is energy storage?

“In simple terms, energy storage provides a way to save previously generated energy and use it at a later time. That energy can be stored as potential, kinetic, chemical, or thermal energy and then can be released in various forms, most commonly as electricity. The ability to bank energy for later use makes energy storage a useful and versatile resource for electric companies and their customers.” – Source EEI, Edison Electric Institute, “Harnessing the Potential of Energy Storage” May 2017

Battery and energy storage components are an important part of DER’s (Distributed Energy Resources) to build systems moving energy generation and storage closer to energy consumption.

For our purposes here, we are using energy storage as it refers to lithium-ion battery technology.

What are the components of an energy storage system?

An energy storage system utilizing battery technology is generally composed of the following components:

  • Batteries including the racking and battery management system
  • The Power Conversion System (PCS) including inverters and transformers
  • The Contractor / Integrator who provides software and the building/containers to house the system
  • The Balance of System (BOS) including civil works, permitting, etc.

How does lithium-ion battery technology work?

Lithium-ion or li-ion battery (abbreviated as LIB) batteries are found in many modern-day devices including smart phones. The price of LIB technology has fallen dramatically in the last few years as they are used in electronics, electric vehicles, industrial applications and on the electric grid.

Lithium-ion batteries are rechargeable.  When the battery is connected to a charger, the lithium ions move in the opposite direction as before. As they move from the cathode to the anode, the battery is restored for another use.  Even in the case of large utility-scale installations, lithium-ion batteries are rechargeable.  A typical use would be for renewable energy sources like wind and solar to charge the batteries for use at another time.  Electricity discharged from the lithium-ion battery is converted from DC power to AC power via a bidirectional inverter.

Lithium ion battery operation