Recent and related:<p><i>Scientists develop ‘cheap and easy’ method to extract lithium from seawater</i> - <a href="https://news.ycombinator.com/item?id=27411631" rel="nofollow">https://news.ycombinator.com/item?id=27411631</a> - June 2021 (290 comments)
$5 of electricity is a near meaningless metric. The real question is how many kWh does the process require to get the 1kg of Lithium? Electricity prices vary widely, so I don't understand why they would use dollar figures, especially on an engineering site.<p>If we know how many kWh of electricity is used to get the Lithium, then we can compare that to how much energy the Lithium would be able to store and release over it's usable life.
Some rough numbers in my head, the total weight of Lithium in the average 18650 battery is probably 25 grams (the other components being other metals like Cobalt).<p>This means that the 1kg of Lithium would be able to make about 40 or so 18650 batteries.<p>The average 18650 battery has an average watt hour capacity of 11 (a good one). So with 40 batteries you have 440wh of storage.<p>The average lifespan of the batteries would be about 1000 cycles... so 440kWh of capacity over the lifetime of the battery.<p>I will assume that the electricity rate they use for the $5 figure is a very cheap $0.10/kWh. Meaning that it would require 50kWh in the extraction process alone to extract enough lithium capable of storing 440kw over it's usable life.<p>I have no idea if this is a good return or not compared to how much energy is spent mining lithium.
Is this the same group that announced they could do this last month? There was a mention on HN.<p><i>His team also aims to enter a collaboration with the glass industry, to develop the LLTO membrane at greater scales with affordable cost.</i><p><i>five dollars of electricity (to extract) 1kg of lithium</i><p>In other words, they have this working on a lab bench, and the cost estimates are pure speculation.<p><i>a copper cathode coated in ruthenium and platinum.</i><p>Ruthenium - US$25,000/kg.<p>Platinium - US$35,000/kg.<p>Anode cost not included in cost estimate.<p>This is going to turn on all the usual cost factors - how often do you have to replace the membrane and the anode, what about corrosion, does it need cleaning, etc. There's no question that this is possible, but a big question is whether it is cost effective.
Why is the news like this? There are only two types of articles: those spelling doom and despair on the world and those championing every millimeter of progress while blind to downsides. It's tiring how much work you have to put in to actually pick these apart to find the little nugget of truth in the middle. But apparently the truth doesn't generate clicks so it's lost to us under a cloud of extreme polarization. Maybe there's some law that the more you abstract the details and write for a layman audience the more polarized the result.<p>Anyways, I expect this one is the latter. It seems the general method is to elecrolyze seawater with a special membrane (lithium lanthanum titanium oxide (LLTO)) and special electrodes (ruthenium and platinum) that only allows lithium ions but not other metals through. "Five dollars of electricity is needed per kilogram", hey that's pretty good. Not so good: did you notice the phrases "seawater", "special membrane", and "special electrodes" in the same sentence? Yeah, that means $$$$$. The quote on that little detail? "His team also aims to enter a collaboration with the glass industry, to develop the LLTO membrane at greater scales with affordable cost." Mhm.<p>But hey, I'm just an idiot that took a chemistry class way back when and my first paragraph was cast at this article unfairly. Maybe we'll be lucky and get one of those awesome HN moments where an expert in the field chimes in, otherwise I hope to see you in 5 years with another headline claiming that this tech was finally commercialized. And good luck to the team! Just don't hold your breath.
Thinking out of the box, I wonder if the ocean could be turned into a giant battery somehow. Considering most population lives closer to the coasts, it would be amazing if it was possible without any environmental harm.<p>Not saying something like electrifying the oceans. But, something like power generation with Wind, solar or tidal energy, and store it in some kinetic form like Norway did with water up the mountain, and then transfer power upon need to the coastal cities.
News media corps are clearly learning! They don't ask questions that suggest bullshit... (whats that law about if the headline is a wuestion the answer is no?)<p>they just directly suggest nonsense now. Cool, cool
Someone built a machine to do this for gold: <a href="https://www.reddit.com/r/askscience/comments/sabgy/scientists_of_reddit_can_the_sullivan_generator/" rel="nofollow">https://www.reddit.com/r/askscience/comments/sabgy/scientist...</a>
Are these practical given the right conditions or just crazy ideas?