Quest for cheaper flow batteries goes on with naphthalene derivatives

Good news! We sure can use some better batteries!

"Flow batteries promise longer-lasting and safer grid energy storage than their lithium-ion counterparts. But, while they don’t need lithium, commercial examples still currently need metals to work, with the highest-performing being vanadium.

Now Chinese researchers have developed a class of carbon-based materials that can work in a flow battery. ...

The research revolves around organic redox-active molecules (ORAMs) ...

The researchers approached the problem with a series of compounds based on naphthalene ...

They were able to make these naphthalene-based substances with a simple process, using electrochemistry.

These compounds dissolved easily, which is important because flow batteries use liquid to store and transfer energy.

And they were stable in air, lasting for at least 40 days without any signs of decay. ...

The process was easy to scale: the researchers made 10kg of material in the lab. ..."

From the abstract:

"The growing global capacity for renewable energy generation necessitates the deployment of energy storage technologies with a combination of low cost, good performance and scalability. With these advantages, aqueous organic flow batteries have the potential to be the system of choice because they could store energy from organic redox-active molecules. Here we report naphthalene derivatives as organic redox-active molecules that exhibit high solubility (~1.5 M) and a stable redox-active framework with no obvious capacity decay over 40 days (50 Ah l−1) in an air atmosphere in flow batteries. We report a battery that runs smoothly even under continuous airflow without obvious capacity decay for ~22 days (more than 600 cycles). A series of spectral analyses and theoretical calculations reveal that the dimethylamine scaffolds improve the water solubility and protect the active centre, ensuring the stability of the molecules during the charge and discharge process. Owing to the success in kilogramme-scale molecular synthesis, pilot-scale stack expansion with notable cycling stability over 270 cycles (~27 days) is attained. The cost benefit evidenced by technoeconomic analysis together with the stability even under open-air conditions indicates the practical value of the present molecular system in grid-scale energy storage."

Quest for cheaper flow batteries goes on with carbon

Researchers Develop Novel Organic Redox-active Molecules for Flow Batteries (original news release)

Air-stable naphthalene derivative-based electrolytes for sustainable aqueous flow batteries (no public access)

Chemical and electrochemical reaction of the naphthalene derivatives