Battery life could be extended by replacing tape that causes self‑discharge

techxplore.com

4 pointsPaulHoule2 comments

Does anyone know if they are using PET tape solely to cover the electrodes (where it can be replaced relatively easily) or are they using it deep inside the lithium cells somewhere where we can't get at it?

EDIT: All of the LiPo cells that I have seen have Kapton over the electrodes. Kapton is a polyimide. It doesn't have the problem the article describes with PET. I'm not seeing PET tape anywhere. Maybe the cheap knock-off Kapton is made from PET?

A while back I did some study of materials for making solar sails and sunshades, both PET and Kapton. These are both used to make high-performance films but they are very different chemically, the first thing that sticks out to me is that PET is made from carbon, hydrogen and oxygen and Kapton also contains oxygen.

I see a lot of Kapton in electronic devices, but I do see people are selling PET film for lithium batteries:

https://www.kingzom.com/green-pet-tape-lithium-battery-termi...

https://patents.google.com/patent/CN112063316A/en

I see a lot of green tape for sale which might confuse people because I usually think of PET tape as transparent.

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