Ray_of_Light
Flashlight Enthusiast
Thank you Newbie for the hard (and dangerous) work!
I want to add just some notes. The positive electrode is the grid, made of an alloy of nickel, and has that black powder distributed in the holes. The black powder is the Manganese Dioxyde mixed with graphite.
The white porous membrane acts as physical separator and ionic conductor. It is wetted with the liquid, organic electrolyte. If the membrane melts, the battery is shorted.
The grey solid film is the lithium, the negative electrode. Once the battery is cut open, the lithium will keep generating hydrogen, as result of presence of water in the air.
The 123s use a wound structure, like Ni-MH batteries, to reduce their internal resistance.
An organic electrolyte must used due to high reactivity of the lithium with any water based compound. It has a specific resistence that is much higher than comparable acqueous solvent, and a wound structure reduces the resistance - since the exposed surface increases.
Alkaline batteries and backup lithium batteries use a non-wound structure (called "bobbin" structure).
No other commercial primary cells, aside from lithiums, use the wound structure, since it is expensive to produce.
Anthony
I want to add just some notes. The positive electrode is the grid, made of an alloy of nickel, and has that black powder distributed in the holes. The black powder is the Manganese Dioxyde mixed with graphite.
The white porous membrane acts as physical separator and ionic conductor. It is wetted with the liquid, organic electrolyte. If the membrane melts, the battery is shorted.
The grey solid film is the lithium, the negative electrode. Once the battery is cut open, the lithium will keep generating hydrogen, as result of presence of water in the air.
The 123s use a wound structure, like Ni-MH batteries, to reduce their internal resistance.
An organic electrolyte must used due to high reactivity of the lithium with any water based compound. It has a specific resistence that is much higher than comparable acqueous solvent, and a wound structure reduces the resistance - since the exposed surface increases.
Alkaline batteries and backup lithium batteries use a non-wound structure (called "bobbin" structure).
No other commercial primary cells, aside from lithiums, use the wound structure, since it is expensive to produce.
Anthony