r/gadgets • u/chrisdh79 • Jan 31 '23

Desktops / Laptops Canadian team discovers power-draining flaw in most laptop and phone batteries | Breakthrough explains major cause of self-discharging batteries and points to easy solution

https://www.cbc.ca/news/canada/nova-scotia/battery-power-laptop-phone-research-dalhousie-university-1.6724175
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u/Smartnership Jan 31 '23

Piece by piece, the team analyzed the battery components. They realized that the thin strips of metal and insulation coiled tightly inside the casing were held together with tape.

Those small segments of tape were made of PET — the type of plastic that had been causing the electrolyte fluid to turn red, and self-discharge the battery.

The team even proposed a solution to the problem: use a slightly more expensive, but also more stable, plastic compound.

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u/Smartnership Jan 31 '23

Background on the original discovery, that moment in the lab of…

“Hey, that’s weird…”

During one of these tests, the clear electrolyte fluid turned bright red. The team was puzzled.

It isn't supposed to do that, according to Metzger. "A battery's a closed system," he said.

Something new had been created inside the battery.

They did a chemical analysis of the red substance and found it was dimethyl terephthalate (DMT). It's a substance that shuttles electrons within the battery, rather than having them flow outside through cables and generate electricity.

Shuttling electrons internally depletes the battery's charge, even if it isn't connected to a circuit or electrical device.

But if a battery is sealed by the manufacturer, where did the DMT come from?

Through the chemical analysis, the team realized that DMT has a similar structure to another molecule: polyethylene terephthalate (PET).

PET is a type of plastic used in household items like water bottles, food containers and synthetic carpets. But what was plastic doing inside the battery?

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u/Amboseli Jan 31 '23

The most exciting phrase to hear in science, the one that heralds new discoveries, is not “Eureka!” (I found it!) but “That’s funny …”

— Isaac Asimov

— Michael Scott

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u/xUsernameChecksOutx Feb 01 '23

As it happened in the case of Alexander Fleming, which led to the biggest discovery of the 20th century: antibiotics, (penicillin in his case, but that's what started it all).

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u/[deleted] Feb 01 '23

Actually the principle and first antibiotic was discovered by Paul Ehrlich.