Feb 01, 2023 17:00:00

It has been pointed out that the cause of the natural discharge of the battery may be deterioration of the tape inside the battery

Battery drains even when you unplug your electronics, turn them off, and don't use them at all. Dalhousie University researchers have identified the cause of this phenomenon, called '

spontaneous discharge ', and are trying to address the problem.

Reversible Self-discharge of LFP/Graphite and NMC811/Graphite Cells Originating from Redox Shuttle Generation - IOPscience
https://doi.org/10.1149/1945-7111/acb10c

Identification of Redox Shuttle Generated in LFP/Graphite and NMC811/Graphite Cells - IOPscience
https://doi.org/10.1149/1945-7111/acaf44

Dal researchers' chance discovery could help extend battery life by replacing tape that causes self-discharge - Dal News - Dalhousie University
https://www.dal.ca/news/2023/01/16/dalhousie-battery-discovery-self-discharge.html

A research team led by Michael Metzger at Dalhousie University is investigating the cause of spontaneous discharge of lithium -ion battery cells, and as part of their research, after exposing lithium-ion battery cells to various temperatures, decomposition I did.

As a result of heating lithium-ion battery cells containing solutions of common electrolytes to different temperatures, the electrolyte solution in the cell at 25°C remained transparent, while the electrolyte at 55°C remained light brown and at 70°C was red like blood.

After that, chemical analysis of the electrolyte solution was carried out to investigate the chemical composition, and it was found that the

polyethylene terephthalate that constitutes the tape used to fix the electrodes of the battery cells chemically decomposed to generate molecules that lead to spontaneous discharge. discovered.

This molecule, called a ' redox shuttle,' makes a round trip between the positive and negative sides of the electrode, causing a natural discharge in the background just like when the battery is being driven, even though it is not actually driving the battery. It is done.

Mr. Metzger said, ``There has been no research on the tapes and plastic films in the battery as the cause of spontaneous discharge, so I did not expect this cause.If you want to suppress the spontaneous discharge of the battery, Consideration is necessary.' 'This is a big commercial discovery. This discovery will definitely help improve battery cells.'

This research has the potential to lead to the adoption of a tape made of a stable material that is less likely to deteriorate in place of conventional polyethylene terephthalate tape, and several companies have already sought to improve battery performance based on the announcement. It is said that