Sciencemadness Discussion Board

Membrane inside Li-ion batteries - useful for anything? possible replacemet for Nafion?

RogueRose - 14-5-2019 at 07:56

I was thinking that this thin plastic membrane must allow electrons to pass through and possibly some ions so I'm wondering if it has any other uses for membrane chemistry. I'm currently working on splicing pieces together to make a larger sheet, IDK if simple heat will work like with mylar and other plastics or if I'll need an ultrasonic welder.

It would be really interesting if this could be used in place of nafion for a hydroxide cell. I have a feeling that it might just be able to be used for this.

Anyone have any ideas about this?

I'm also amazed at the mass of the black material inside the battery. I think it weighs almost 2x what the Al + Cu weigh together. I've found that it's pretty simple to separate the black stuff from the Al/Cu, just place the roll in hot water (hotter the better), take out and allow to cool, then just unroll and wipe it off as you unroll it. I got long pieces almost the length of the membrane but I think my batteries were not damaged from overcharging before they died. damaged batteries will be messier.

[Edited on 5-14-2019 by RogueRose]

Ubya - 14-5-2019 at 09:11

The black stuff is graphite but contains also manganese, nickel and Cobalt, useful metals for home chemistry:D

As for the membranes, they should be in polyethylene, they should survive in an alkali cell.
Do a small test cell and let us know how it went