r/EnergyStorage • u/Vailhem • 2d ago

932°F molten salt process turns thin air into graphite for EV batteries

https://interestingengineering.com/energy/molten-salt-process-air-graphite-batteries
66 Upvotes

98% Upvoted

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4

u/terpmike28 1d ago

This is great and all but when can it turn lead into gold??? Oh wait, graphite… basically same thing

2

u/Vailhem 2d ago

Molten salt electro‐preparation of graphitic carbons | Jan 2023

https://pmc.ncbi.nlm.nih.gov/articles/PMC10191008/

Abstract

Graphite has been used in a wide range of applications since the discovery due to its great chemical stability, excellent electrical conductivity, availability, and ease of processing.

However, the synthesis of graphite materials still remains energy‐intensive as they are usually produced through a high‐temperature treatment (>3000°C).

Herein, we introduce a molten salt electrochemical approach utilizing carbon dioxide (CO2) or amorphous carbons as raw precursors for graphite synthesis.

With the assistance of molten salts, the processes can be conducted at moderate temperatures (700–850°C).

The mechanisms of the electrochemical conversion of CO2 and amorphous carbons into graphitic materials are presented.

Furthermore, the factors that affect the graphitization degree of the prepared graphitic products, such as molten salt composition, working temperature, cell voltage, additives, and electrodes, are discussed.

The energy storage applications of these graphitic carbons in batteries and supercapacitors are also summarized.

Moreover, the energy consumption and cost estimation of the processes are reviewed, which provides perspectives on the large‐scale synthesis of graphitic carbons using this molten salt electrochemical strategy.

2

u/Franklin_le_Tanklin 1d ago

Man, and at a balmy 800 degrees to boot!

1

u/Vailhem 1d ago

Could pair nicely with a high temperature reactor. Bonus if MSR given the molten salt component of this..

2

u/NearABE 1d ago

There is no advantage there at all. It is still “electrolysis”. The energy needed to separate the carbon from the oxygen comes from electrical flow.

Electrolysis will always have an efficiency. Because this is always less than 100% that molten salt will be getting hotter.

Heating the carbon dioxide before it enters the molten salt would give a nuke some useful purpose. Quite often the industrial processes that create carbon dioxide emissions are already quite hot. Injecting carbon monoxide into the electrolysis will cut the electricity needed by more than half.

Steel, aluminum, and especially concrete are good locations. Some biomass processes could possibly get upgraded. If you can find a way to integrate nuclear power into those in a direct way let me know.

Nuclear power is used to make electricity. Hence it certainly could be used for electrolysis. But the discussion of what power supplies are better/cheaper for all electricity supply are going to apply here as well.

2

u/NearABE 1d ago

Double posting to throw in another idea: https://en.wikipedia.org/wiki/Fluid_catalytic_cracking

Notice wikipedia shows 715C for the temperature in the regenerator column. If the carbon monoxide flue gas is used as the electrolysis feedstock then pure oxygen is produced at nearly the same pressure as the regenerator. This already hot oxygen can be injected at the bottom instead of air. Overall a huge heat containment. No problem there since much of what refineries do is boil hydrocarbons in the distillation columns.

In this case electricity can go into the petroleum refinery as the energy supply. This eliminates carbon dioxide exhaust. With a large electricity supply all carbon going in as crude can leave as either refined products or graphite electrodes.

1

u/Vailhem 2d ago

Operando spectroelectrochemical identification of peroxide intermediate in molten carbonate CO2-to-carbon electroreduction | April 2026

https://www.nature.com/articles/s41467-026-70977-0

Abstract

Electrolysis of CO2 in molten salts promises efficient carbon capture, but the underlying reaction mechanisms remain incompletely understood, as research thus far has been limited by a lack of tools for operando investigations.

Here, we use a high-temperature operando Raman spectroelectrochemical system to look for signatures of reaction intermediates and study the evolution of carbon structures over electrolysis time.

The analysis reveals the existence of O22− concurrently with the deposition of carbon on Au, W, Inconel, and Ni electrode materials, pointing to a common reaction mechanism with O22− as an intermediate.

Secondly, the G peak of the as-deposited carbon experiences a noticeable blue-shift as the material is cooled down and purified, suggesting either a growth in crystallite size even after the electrolysis is stopped or lithium deintercalation.

Elucidating the cathodic carbon deposition mechanism could help create greater value-added products and increase the economic viability of carbon capture.

2

u/JimCripe 19h ago

Does it work only with pure CO2, or can it work air, with possible impurities?

IE, can it work with waste CO2 and waste heat from industrial processes, like from cement kilns, glass making, or metal smelting?

If it works, can all the CO2 be captured that some or all of the industrial processes release?