Understanding Battery Energy Storage Technologies

Battery Energy Storage Systems - Lithium vs. Vanadium Flow

As we have explained in a previous blog, battery technology is improving, and costs are coming down. In this blog we look at the main technologies available, particular when it comes to Commercial & Industrial applications. At Nesa we recommend two technologies, depending on the customer’s specific needs, budget and timeframe – Vanadium Flow and Lithium. But how does each technology work and what are the advantages and disadvantages?

When assessing which technology is best it’s good to consider the typical functions of battery storage:

1. Maximising solar consumption (store excess solar energy for use after solar hours)
2. Tariff Arbitrage (load shifting) Charge the battery during Off Peak grid rates and discharge it during Peak grid rates.
3. Back-up OR Diesel Generator Offset
4. Peak Demand Shaving

Lithium in a Nutshell:

Most people are aware of the term lithium-ion or Li-ion battery. But how do these batteries work? Li-ion batteries compose of cells in which lithium ions move from the negative electrode through an electrolyte to the positive electrode during discharge and the opposite way when charging. This technology was developed in the 1970’s and has since been used for everything from cellphone batteries to electric vehicles and Renewable Energy systems.

Key Features:
  • Runs at 70-80% capacity for 12-18 years. Loses capacity over time.
  • Creates waste and will need to be recycled.
  • Although proven safe, it is nonetheless still flammable and explosive.
  • Derates in high temperatures and requires cooling systems.
  • Better roundtrip efficiency ±93%
  • Lifespan of 12-18 years. Replacement of cells is virtually a complete replacement.
  • End of life value is limited.

Vandium in a Nutshell:

Vanadium Flow Batteries (VFB) employ vanadium ions as charge carriers. Due to their bulk, VFB are generally used in larger commercial and industrial applications where energy storage is required.

Key Features:
  • Run at 100% capacity forever
  • Electrolyte can be re-used. Retains end of life value.
  • Non-flammable as it is water-based.
  • Operates in wider range of temperatures
  • Lower roundtrip efficiency ±70%
  • Longer lifespan: 25-30 years. Only hardware that may need to be changed. Electrolyte can be reused, which is the most expensive portion.

Let Nesa’s team of engineers analyse your load profile and advise on whether a Battery Energy Storage System could save your business money and which of the technologies would be best. Contact us on info@nesapower.com