Bad Battery Project

In this Bad Battery Project, a retail customer brought us in a laptop that was no longer charging. After testing the charger to make sure it was working we had to take the laptop apart. To our surprise, we found a very bloated battery inside the laptop. There were also signs that the battery had been leaking. So after removing the battery and cleaning up the mess inside the laptop. We ordered the customer a new battery and installed it and the customer was up and running once again.

What Causes this to happen?

Swollen batteries are the result of two things: energy density and heat. The swelling is the result of too much current coursing, in a noncontrolled fashion, inside a cell of the battery. Which causes a build-up of heat and gas. This happens as the materials inside a battery decay. Or is subjected to stress or physical damage over time.

A given laptop battery is made up of several discrete cells. This means issues can arise in just one, or more than one, of them. You’ll often see laptop batteries described as, for example, four-cell or six-cell, indicating the internal structure of the battery. (Some laptops, usually business models, give you a choice of battery capacity/cell count at the time of purchase, but that is less common than in the past.) The fact that laptops seldom come with removable batteries anymore (in the sense of, you can swap them in and out without opening up the chassis) exacerbates the problem.

“The reason why these batteries swell is that the electrolyte that separates the layers between the wrap degrade, and when that degrades, it changes into gas,” says Arthur Shi, lead technical writer at iFixit.com. “Now that the electrolyte is degraded, things are no longer insulated and so they start shorting, and that causes a hot spot later. That can eventually cause it to do a thermal runaway, which means it can even start a fire.”

Common Causes

“In an application where you have a system plugged in 24/7, after a number of years your likelihood of getting a swollen battery increases,” says Phil Jakes, principal engineer and director of strategic technology at Lenovo. “The other thing that drives it is heat. Batteries don’t like to be hot, and there’s a chemical process that gets kicked off when a battery gets over 100 degrees.”

Another common cause is mechanical damage to the battery. That might be caused by a blow to the laptop itself, or damage done when changing out it (or messing with other components around it). Striking a hard surface and denting the casing can cause a swelling condition, as can exposure to excessively high temperatures. Also, the damage inflicted to the exterior of your device can transfer to the battery and cause it to overheat and swell.

What should I do?

If you think this is happening to you be sure to schedule an appointment with our team for a free estimate ASAP. Click here to see some of our other in-shop repair services available for you.