https://www.cell.com/joule/pdf/S2542-4351(18)30292-7.pdf : "Lithium Metal Extraction from Seawater"

> Based on the consumption rate projected for 2050, the residual lithium reserve on land will be exhausted by 2080

> In contrast, the ocean contains 230 billion tons of lithium, an amount four orders of magnitude larger than the lithium reserves on land

> our prototype device can be powered by a solar panel and metallic lithium can be directly generated during the lithium extraction process

What exactly do they mean by "seawater"? Not all seawater is exactly the same, chemically speaking. I have actually measured "seawater" before, and the chemistry of the water at a single location can vary wildly from day to day. I just want to know under what conditions they tested their prototype!

THIS IS NOT BAD FAITH FAUX IGNORANCE. I AM ACTUALLY CURIOUS ABOUT THIS.

Lithium content varies as much as salt content, but one thing is certain: the open seas are consistently salty.

That's only if you take the average of all the measurements collected across the entire ocean for decades. In one spot, salinity is not consistent. Patterns of evaporation and rainfall affect not only salinity but also the presence of organic matter and other random contaminants. Such fluctuations are most pronounced at the surface, where this device is meant to operate.

It's the substance that composes those 75% of the surface of our planet that we call "sea".

How much seawater does that process per day?

Yesterday I learned that Sodium batteries might become a contender to Lithium batteries. And they are safer.

Sodium is very clearly a contender for stationary batteries. It may even be competitive for surface mobile applications like cars... But there is just no way it can compete on air transport.

I keep being intrigued by vanadium redox flow batteries, and I've seen some in the real world in stationary applications. And the prospect of instant charging by spit-swapping in a mobile application is pretty wild.

How scarce is vanadium, though?

Vanadium has an horrible weigh/charge ratio. That's why it's used in stationary applications.

Sodium redox flow batteries are all the hype nowadays, because sodium is much cheaper, sulfur for the oxydizer is also very cheap, weight/charge is very high, and volume/charge (important for stationary applications) is also much higher. But I think it's stuck in a patent minefield.

It’s like 2 percent by mass of spent iron slag.

Now now, no need to be rude.

/