Flow Batteries
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Flow Batteries
Subject: Science & Tech
Section: MSc
Context- Can flow batteries support India’s renewable energy pivot?
Concept-
- India’s ambition of creating re newable energy capacity of 500 GW by 2030 cannot be realised without large scale storage systems.
- It is generally accepted that conventional battery systems cannot provide an affordable solution.
Flow Batteries:
- In flow batteries, energy is stored in two liquid electrolytes in separate tanks.
- When you charge, the energy supplied urges electrons from the electron poor side to move to the electron rich side — like taking water uphill — creating a potential difference.
- During discharge, the reverse happens — electrons flow from the electron rich side to the electron poor side.
- The flow of electrons is electricity. Gaining electrons is a ‘reduction reaction’, losing electrons is ‘oxidation’, hence ‘redox’.
- The conversion of energy from chemical to electrical happens in a cell, which is split into two half cells by a membrane.
- Usually, vanadium is used as an electrolyte.
Significance : Flow batteries bring some significant advantages.
- They are modular — one can keep increasing the energy storage capacity by simply raising the volume of the electrolyte tanks.
- The separation of storage capacity and power is a notable advantage. It can be compared this to an internal combustion engine in cars. The size of the engine determines the power; if the manufacturer wants the car to go a longer distance in one fuelfill, one only has to increase the fuel tank size.
- They can store power for long durations.