The multi-billion-dollar future of clean energy was unlocked by a trip to the hardware store for bathroom tile supplies.

Twenty-five years ago, MIT Professor Yet-Ming Chiang bought a tube of glass-etching cream to turn clear glass blocks translucent. He noticed it worked by “eating away” at the surface. Decades later, that mundane trip provided the missing link to break China’s monopoly on the global electric vehicle supply chain.

Writing in Science, Chiang and a team of researchers unveiled a new method to extract lithium from hard rock at room temperature. The process cuts conventional costs in half. It virtually eliminates mining waste. Most importantly, it completely reshapes the geopolitics of critical minerals.

The U.S., Europe, and Australia have vast amounts of lithium trapped inside a rock mineral called spodumene. Yet, China refines the vast majority of it.

“By 2040, we need to quadruple production of lithium globally, which amounts to hundreds of new lithium-producing assets,” said Camden Hunt, a former project manager in MIT’s Center for Electrification and Decarbonization of Industry. 

Hard rock is everywhere, but cracking it open has been a nightmare.

Hard rock mining

Standard refining is a brute-force process. Rocks must be roasted in massive kilns at temperatures exceeding 1,000°C, then subjected to heavy acid treatment. It is energy-intensive, incredibly expensive, and leaves behind mountains of toxic slag. Because Western nations lack the infrastructure or environmental capacity to accommodate this footprint, they ship raw rock straight to China for processing.

The new MIT process changes it by borrowing a page from that hardware store etching cream.

Spodumene rock is essentially made of three things: lithium, aluminum, and silica. Silica bonds are tough; hence, standard mining tries to dissolve everything else first. Chiang’s team used a liquid reagent made of water and ammonium fluoride — the active chemical in glass etchant — to do the exact opposite. They dissolved the silica first.

The results were immediate. The rock dissolved smoothly at room temperature. No extreme heat required.

From there, the team pioneered what they call “nose-to-tail mining.” The entire rock was transformed into high-value commodities through precise separation of dissolved elements. The recipe yields battery-grade lithium salts for electric-vehicle cathodes, smelter-grade alumina for aluminum production, and highly reactive silica perfectly suited for green cement.

Closed-loop process

Even the chemical solvent is entirely recycled. During the reaction, ammonia gas is released. The gas was captured and fed back into the loop, thereby regenerating the starting ammonium fluoride.

The system runs in a literal circle. Waste approaches zero.

To demonstrate its viability, the researchers tested the chemical bath on 17 different spodumene sources from around the world. It worked every time. The economics are equally disruptive, lowering hard-rock mining costs to a level directly competitive with South American brine extraction.

The commercial roll-out is already underway. The team has spun the technology out into a startup called Rock Zero, which is currently scaling it at Boston’s tough-tech incubator, The Engine.

“Our central thesis is that if you can find an easier way to crack the rock, get lithium out, and make battery-grade lithium salts, you can change the lithium market. It aligns with the recent push to onshore production of critical minerals in the U.S,” Hunt added. 

To evaluate the commercial feasibility of the system, Chiang challenged the team to analyze global scaling data, reagent costs, and energy requirements. 

Their calculations confirmed that global spodumene reserves are sufficient to support 100 terawatt-hours of battery production, and that the volume of the resulting co-products aligns perfectly with existing global commodity markets. 

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