Canadian research team discovers widespread manufacturing flaw in most device batteries

An assistant professor at Dalhousie University, Nova Scotia has come forward with a discovery that could change how batteries in personal devices are manufactured.

Micheal Metzger, part of a research team at the university, says that unexpected battery drainage is likely due to a widespread manufacturing flaw.

The group of Halifax-based researchers has determined that the problem stems from tiny pieces of tape that hold the components of the battery. These pieces are said to be made using the wrong type of plastic. According to Metzger, most batteries are experiencing a phenomenon known as “self-discharge.” This is caused by the battery’s electrons being unable to correctly flow through connected cables, powering a circuit, before returning to the battery. This causes the battery to be depleted internally and a device to lose its charge, even if it’s off.

“These days, batteries are very good,” Metzger said to the CBC. “But, like with any product, you want it perfected. And you want to eliminate even small rates of self-discharge.”

Dalhousie University’s battery lab is being used to test dozens of experimental battery cells. The research team is charging them and discharging them in hot environments, with temperatures upwards of 80 degrees Celsius. The team aims to learn why a battery fails over time in order to tweak its electrodes, whether positive or negative or change the electrolyte fluid.

Over the course of the team’s testing, the battery components were analyzed. As such, the team discovered that the inside casing of the battery was being held by metal, insulated coil, and tape. The sections of tape were comprised of polyethylene terephthalate (PET), commonly found in water bottles and other items. As it turns out, the use of PET leads to self-discharge within the battery.

This discovery has been public since November 2022. The Halifax research team proposes the use of a slightly more expensive plastic compound in batteries to solve the issue. A durable, more stable option is polypropylene. This compound is commonly used in reusable water bottles and doesn’t decompose as quickly as PET.

Whether or not manufacturers pick up on this discovery and adopt new procedures is another story.