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Stanford researchers make rechargeable batteries that store 6x more charge

news.stanford.edu

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Re: Stanford researchers make rechargeable batteries that store 6x more charge

#61

Post by BenjiWiebe »

FabHK wrote: post #24
Robotbeat wrote: post #3

Yet again, the useless milliamp-hours per gram for one component of a cell instead of actual energy per unit mass for a whole cell. What is the Watt-hours per kilogram????

Need to multiply by the (average) voltage, and incorporate a fudge factor for the other components of the cell, I think. (P = UI, where P is power in Watt, U voltage in Joule per Coulomb, I current in Coulomb per second. And what we seek is specific energy, ie energy per mass, in J/kg or Wh/kg.)

Watts = Volts * Amps

Any reason you've defined it as: (Amps * Seconds * Volts) / (Amps * Seconds) * (Amps * Seconds * Seconds) ?

Fairly sure but not positive that I've reduced the units to base SI units correctly...

Re: Stanford researchers make rechargeable batteries that store 6x more charge

#63

Post by specialist »

malchow wrote: post #45

Novel chemistries in nano scale in the lab are fun to puzzle about, but pure silicon anode Li-ion batteries really are coming in the next six months, notably from Enovix, and will actually change things. A 2x density upgrade that's real is a whole lot more interesting than a 6x density upgrade that isn't ready for commercialization.

Any news site recommendations for us curious noobs? I've been watching The Limiting Factor. I don't think I'd heard about Enovix yet.

https://www.youtube.com/channel/UCIFn7ONIJHyC-lMnb7Fm_jw/vid...

Update: Scanning your posts, you're in the biz. Of course you have a bead on things. Open to recommendations, nonetheless.

Re: Stanford researchers make rechargeable batteries that store 6x more charge

#64

Post by xor99 »

anoncow wrote: post #2

https://en.m.wikipedia.org/wiki/Sodium-ion_battery

This research has been ongoing for a long time:

Development of the sodium-ion battery took place side-by-side with that of the lithium-ion battery in the 1970s and early 1980s. However, by the 1990s, it had become clear that lithium-ion batteries had more commercial promise, causing interest in sodium-ion batteries to decline.

Re: Stanford researchers make rechargeable batteries that store 6x more charge

#65

Post by AtlasBarfed »

malchow wrote: post #59
AtlasBarfed wrote: post #54

Earlier quoted context omitted.

Have these been independently tested with production form factors? Battery startups seem to have a lot of middle-level fraud in them where they have nice demonstration piddly level cells with great numbers that the internal teams know won't scale to real uses. I did see they are actually funding a factory... but I only saw a couple stories on "wearables" which implies very small batteries. Ugh, and a SPAC. I really w…

Yes, they've been independently tested with production form factors at sampling quantities by major global OEMs: https://ir.enovix.com/static-files/9231246c-a419-46bb-be35-a... . So this is the real one. You're right – lots of bad actors in the battery space. Investors don't really understand how wide the chasm is between prototypes and low-DPPM autoline production ready for grown-up purchases.

Well I'm rooting for them, battery density has kind of stalled at a chemistry level it seems, I haven't seen as many exciting announcements like there were in 2020.

Re: Stanford researchers make rechargeable batteries that store 6x more charge

#66

Post by FabHK »

BenjiWiebe wrote: post #61
FabHK wrote: post #24

Earlier quoted context omitted.

Need to multiply by the (average) voltage, and incorporate a fudge factor for the other components of the cell, I think. (P = UI, where P is power in Watt, U voltage in Joule per Coulomb, I current in Coulomb per second. And what we seek is specific energy, ie energy per mass, in J/kg or Wh/kg.)

Watts = Volts * Amps Any reason you've defined it as: (Amps * Seconds * Volts) / (Amps * Seconds) * (Amps * Seconds * Seconds) ? Fairly sure but not positive that I've reduced the units to base SI units correctly...

ha, you're right, the Ampere is the SI base unit for purposes of definition, but the Coulomb is arguably the conceptually simpler one... (though Volt is definitely derived). So, in terms of "intuition" (left) and SI base units (right) you have:

  Watt   = J s^-1 = N m s^-1 = kg m^2 s^-3
  Volt   = J C^-1 = N m A^-1 s^-1 = kg m^2 s^-3 A^-1
  Ampere = C s^-1 = A

Re: Stanford researchers make rechargeable batteries that store 6x more charge

#67

Post by malchow »

specialist wrote: post #63
malchow wrote: post #45

Novel chemistries in nano scale in the lab are fun to puzzle about, but pure silicon anode Li-ion batteries really are coming in the next six months, notably from Enovix, and will actually change things. A 2x density upgrade that's real is a whole lot more interesting than a 6x density upgrade that isn't ready for commercialization.

Any news site recommendations for us curious noobs? I've been watching The Limiting Factor. I don't think I'd heard about Enovix yet. https://www.youtube.com/channel/UCIFn7ONIJHyC-lMnb7Fm_jw/vid... Update: Scanning your posts, you're in the biz. Of course you have a bead on things. Open to recommendations, nonetheless.

The best journalist in the space is Steve Levine — I’d start there.
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