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A comment on 94-year-old Lithium-Ion Battery Inventor Introduces Solid State Battery. Parent comment

Re:94-year-old Lithium-Ion Battery Inventor Introduces Solid... by hwillis on Thursday March 02, 2017 @07:02PM (#13779570)
Yeah... I'm not sure what that is. They also conflate mA and mAh a few times. It's kind of confusing.

I think that they are using the weight of lithium metal rather than the actual battery. That's the only thing that makes sense, as the specific energy of PURE LITHIUM is barely above that 10.5 Wh/g figure. The 10.5 must come from the energy drop to sulfur intercalation, which is at .4v. The 8.5 Wh/g figure comes from the reversable voltage range. It's either that or their numbers are off by 100x.

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Re:94-year-old Lithium-Ion Battery Inventor Introduces Solid... by mtdewcmu on Thursday March 02, 2017 @07:56PM (#13779881)
With units of Wh/g (Li metal), my impression is that it's measuring grams of pure lithium.
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Re:94-year-old Lithium-Ion Battery Inventor Introduces Solid... by hwillis on Thursday March 02, 2017 @09:18PM (#13780249)
Yes, but its not a useful measure. Most batteries will have similar specific energy when compared by lithium directly. How effectively the lithium is used is also almost completely irrelevant to the cost, weight and size of the battery. It's just a really weird thing to measure and they don't actually specify what the grams are of- lithium or sulfur are just the only things that make sense.
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Re:94-year-old Lithium-Ion Battery Inventor Introduces Solid... by yorwba on Thursday March 02, 2017 @09:57PM (#13780413)
The grams are specified as "g (Li metal)", so grams of lithium.
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Re:94-year-old Lithium-Ion Battery Inventor Introduces Solid... by hwillis on Friday March 03, 2017 @12:49AM (#13781010)
Yes, but on first read I thought that they were specifying for the battery using lithium metal as they were also talking about sodium and nonmetallic lithium. It's just so random I didn't read it correctly.
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Re:94-year-old Lithium-Ion Battery Inventor Introduces Solid... by yessql on Friday March 03, 2017 @12:14PM (#13784326)
Is lithium the most expensive material in the chemistry?
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Re:94-year-old Lithium-Ion Battery Inventor Introduces Solid... by mtdewcmu on Friday March 03, 2017 @05:25PM (#13787410)
I made a cursory attempt to find the answer, and I was unsuccessful. I did find this[1], though (from my alma mater).

[1] https://engineering.cmu.edu/media/press/2016/12_13_whitacre_...

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Re:94-year-old Lithium-Ion Battery Inventor Introduces Solid... by yessql on Friday March 03, 2017 @12:13PM (#13784312)
That makes sense... Li is typically 4% of the weight of a Li-Ion battery, so that would align pretty well.
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