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Scientists Have Created Batteries Using Carbon Dioxide From Atmosphere (thelatestnews.com)

Posted by BeauHD on from the out-with-the-old-in-with-the-new dept.

An anonymous reader writes: While climate change talks progress on how to reduce carbon dioxide emissions, an interdisciplinary team of scientists have worked out a way to reduce carbon dioxide already existing in the atmosphere. The focus is on the batteries used by electric automobiles. Researchers have found out that the graphite electrodes in the lithium-ion batteries could be replaced with carbon electrodes sourced from atmospheric carbon dioxide. The experiment started with the use of a solar-thermal electrochemical process (STEP) to convert carbon dioxide into carbon. STEP uses solar energy as the source of the thermal and electrical energy required for the dissolution of the atmospheric carbon dioxide to its constituent elements -- carbon and oxygen. The team then used the carbon generated to create carbon nanotubes/nanofibers. They then incorporated these carbon nanotubes into lithium-ion batteries by using them as the positive electrode or anode. While the carbon is used in the manufacture of carbon nanotubes, the oxygen is channeled back to the generator to boost the combustion efficiency of the generator. The increased efficiency will balance the electricity consumption of STEP. In the end, the fossil fuel electrical power plant could have zero net carbon dioxide emissions.

9 of 63 comments (clear)

  1. How much? by Anonymous Coward · · Score: 3, Interesting

    So, how many tons of additional CO2 were released in order to remove a tiny bit of CO2 from the atmosphere?

    1. Re:How much? by VernonNemitz · · Score: 3, Insightful

      "In the end, the fossil fuel electrical power plant could have zero net carbon dioxide emissions."
      Looks to me that in the end it will actually be solar power replacing fossil-fuel power.

    2. Re:How much? by Applehu+Akbar · · Score: 3, Insightful

      Rooftop solar does a good job of zeroing out the power usage of the single-family home under it, but what happens when those solar panels are on the minuscule roof of a high-rise apartment complex?

      And most especially, what happens when your country wants to smelt steel? I suppose you can outsource all the steel production to a nuclear country like South Korea.

  2. The thermodynamics is a off here... by Hussman32 · · Score: 4, Insightful

    If they are going to reduce carbon dioxide to carbon and oxygen, then at a minimum they will need to add -394.39 kJ/mol of CO2 to the system because of the Gibbs Free Energy of Formation, which would yield 12 grams of carbon. and 32 grams of oxygen.

    If we're looking at replacing one metric ton of carbon per hour, then this process would need 1,000,000/12 = 83,333 moles carbon*393 kJ/3600 seconds hour = 9.1 MW of energy minimum, assuming 30% efficiency, would yield the need for 30 MW of solar panels. At 5 acres per megawatt, they would need 150 acres of land.

    Again, trees look like the better option for carbon removal.

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    1. Re:The thermodynamics is a off here... by Mostly+a+lurker · · Score: 4, Insightful

      I have not checked your math, but I assume you are correct. There is one flaw in your logic, however. Batteries do not grow on trees.

    2. Re:The thermodynamics is a off here... by fizzup · · Score: 3, Insightful

      Again, trees look like the better option for carbon removal.

      Let's see!

      According to these guys, a tree removes about 22kg of co2 per year. How much space does a tree take? I would guess about 10 square meters. It depends a bit on the tree, I guess. 150 acres is 600,000 square meters, or about 60,000 trees.

      There are about 8,800 hours in a year, so we can now estimate the removal rate of carbon dioxide in metric tonnes per hour for a forest. Whee!

      0.15 tonnes per hour = (60,000 trees x 22 kg/tree-year) / (8,800 hours/year * 1000 kg/tonne)

      Your one tonne of carbon represents 3.7 tonnes of carbon dioxide. Under the assumptions of your post (which I'm a little unsure of), this proposal is almost 25 times as effective as a forest!

    3. Re:The thermodynamics is a off here... by Solandri · · Score: 3, Informative

      His math is right. The bulk of the energy release when creating CO2 is from the step going from atomic carbon and atomic oxygen (dG = 0).to CO2 (dG = -394.4 kJ/mol), not the decomposition of for example CH4 (methane, dG = -50.8 kJ/mol). In fact it would take more energy to go from CO2 to atomic carbon and oxygen, than was originally released when you burned the CH4.

      Basically, this process amounts to you taking the exhaust and soot from someone else burning a tree, then you burn 2-3 trees to generate enough energy to convert that soot and CO2 back into its atomic constitutents, then you convert it into a battery. So yeah batteries don't grow on trees, but it would take less energy to make the battery starting with the tree than what these guys are doing.

      CO2 and H2O aren't just byproducts of chemical reactions which can be converted into C, H2, and O2 if you "just" knock the atoms apart. They sit very far down the energy potential well. All the energy that you get when you burn fossil fuels comes from lowering the C, H, and O down the energy potential well (creating CO2 and H2O in the process). Decomposing them back into their constituent atoms (knocking the atoms apart) requires pumping an equivalent amount of energy back into them.

      Factor in inefficiencies and you're usually looking at having to put 2-3x as much energy in as you originally got out when you burned the fossil fuel. At that point you're better off just using that energy directly as electricity to power society - prevent the fossil fuel from being burned in the first place, instead of trying to uncreate the CO2 that was formed from burning the fossil fuel.

  3. Why? by penguinoid · · Score: 3, Insightful

    Researchers have found out that the graphite electrodes in the lithium-ion batteries could be replaced with carbon electrodes sourced from atmospheric carbon dioxide.

    Why? What's the benefit of getting the carbon from the atmosphere, as opposed to from less energy-intensive sources? Especially since a large proportion of our energy sources put carbon into the atmosphere.

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  4. Source? by PopeRatzo · · Score: 3, Insightful

    Before we get too far into the celebration over the fact that we'll be able to use all the fossil fuels forever and there will never be a downside, I'm just curious. Does anyone know anything about the website that is the source for this story? thelatestnews.com, it's called and it looks a little weird. There isn't a single link in the actual article to anything related to the actual scientists or anything published about this work. Just a YouTube video. I also found this story in the "Business" section of the site:

    http://www.thelatestnews.com/b...

    They start by saying in the title that this "bitwalking" thing is financial nonsense, but by the end of the article, they're saying why they think it's a brilliant idea.

    I'm just a little concerned about who is behind this news site, but then I'm naturally suspicious.

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