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by vessenes 34 days ago
Not clear from the very fluffy press release how one gets this pyrimidone to start releasing enough energy to boil water while it maintains 60% better energy density than lithium ion batteries.

I’d personally want to understand that before making any big plans, but this sounds cool.
3 comments
flopsamjetsam 34 days ago
Yeah, you'd think they'd include that.

https://www.science.org/doi/10.1126/science.aec6413

"Upon treatment with acid, that bond breaks to release more than a megajoule per kilogram of the compound, enough to rapidly boil water from a solution."

That's from the editor's summary (I haven't had time to read the paper).

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kenhwang 34 days ago
From the article:

> When exposed to a trigger -- such as a small amount of heat or a catalyst -- the molecule snaps back into its original form, releasing the stored energy as heat.

From the paper abstract, the catalyst is HCl. I don't have access to the full paper, so I don't know how they separate the HCl from the MOST to neutralize it to be rechargeable again.

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kadoban 34 days ago
"A small amount of heat or a catalyst". Well, that sounds unstable. So any random contamination and you have a runaway reaction.
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kenhwang 34 days ago
From what I've seen of the paper, it seems like the catalyst is needed for a full energy release reaction. Regular batteries also have rapid energy release with unintended contamination of a chemical (water), and we still generally have no problems during regular usage.

The reaction triggered by heat doesn't release all the stored energy, which would be the bigger concern for unintended runaway reactions.

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ludston 34 days ago
A small amount of heat is a lot harder to isolate from than water though.
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gus_massa 34 days ago
As a sibling comment says, in the paper the catalyst is acid and I can't find the release using heat in the paper. Is that an hallucination in the press article?

(Note: At high enough temperature the thermal energy will be high enough to go over the energy wall from the high energy isometric to the normal one. So it's plausible. But with high enough temperatures a lot of nasty things can happen, like total decomposition or just burning. So it may not be a good strategy to make a rechargable baterry.)

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chrisbrandow 34 days ago
They experimental details in the paper itself. Tl;dr you lower the pH.

https://www.science.org/doi/10.1126/science.aec6413

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