Inside GBS cells

kennybobby said:

Can you determine how they are constructed?

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Same as all other prismatic cells: many sets of cells in a bag, many bags in a case. The positive tabs from each cell are pressed together, and clamped to the case positive terminal. Same for the negative terminal.

While the guts of a prismatic cell are somewhat similar to a pouch cell, they are different in at least one major point: each bag is not sealed (pouch cells are sealed), so they share the gaseous portion of the electrolyte. The electrolyte is poured into the case through the plug at the top, at the end of construction.

Re: hard to pour peanut butter...

kennybobby said:

electrolyte... has the viscosity of grease and is spread on the foils like peanut butter.

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Actually, I am not so sure. I do know of solid electrolytes for pouch cells. I do believe that many (all?) cylindrical cells use liquid electrolyte. But you're making me doubt what I understood about prismatic cells.

reference?

Could someone with more direct know-how chime in?

swoozle said:

The Rickard thundersky dissection video shows essentially no free liquid and the anodes/cathodes barely wet with electrolyte.

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Correct: as my reference (above) says, the electrolyte is very precisely metered.
Only the exact amount of electrolyte is poured in that will be completely absorbed by the cell, leaving no unabsorbed electrolyte. If indeed it is poured in a prismatic cell (as I remember being told). If is "spread like peanut butter", then no. We're looking for someone who actually knows the answer. I am not an expert in Li-ion chemistry and manufacture.

And, indeed, no liquid poured from any of the 4 GBS cells we just opened.

kennybobby said:

see if the electrode foils and electrolyte are actually visible,,,

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They are visible: you can see them clearly in the picture. The white sheets are the separators.

kennybobby said:

... or if these might be separately sealed pouches?

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They are not separate pouches. That is, they are not a bunch of individually sealed bags.