Batteries play a crucial role in providing short-term flexibility to the energy system, offering advantages such as geographical and sizing flexibility. Unlike some other storage systems, such as pumped hydro storage, batteries do not require specific environmental conditions, enabling their deployment closer to where flexibility is needed. Here’s a breakdown of various battery storage technologies:

1. Lithium-ion batteries:

• Widely adopted and technologically advanced, particularly accelerated by the electric vehicle (EV) industry.
• Versatile applications, ranging from end-use appliances like EVs to grid-scale installations.
• Mainly utilized for power grid services such as frequency regulation and flexible ramping, increasingly considered for variable renewable energy (VRE) support.

2. Sodium-sulphur batteries:

• Composed of sodium (Na) and sulphur (S), operates at high temperatures.
• Suitable for applications with durations above 4-hour periods.
• Deployed at grid-scale in various regions but have disadvantages including shorter lifecycles and lower charge retention.

3. Lead-acid batteries:

• Lower cost compared to lithium-ion batteries but with drawbacks such as lower energy density and shorter lifespan.
• Less scalable and losing market share to lithium-ion batteries due to limitations in multi-MW and GW-scale applications.

4. Flow batteries:

• Large, rechargeable batteries with external liquid electrolyte tanks.
• Longer lifespan (20-25 years) and nearly unlimited recharge cycles.
• Utilize cheaper and more abundant materials like iron, salt, and water, but face challenges such as high upfront costs and electricity demand associated with operation.

While lithium-ion batteries dominate the market, each technology offers unique advantages and limitations, influencing their suitability for various applications in the evolving energy landscape.