To calculate the potential date of death for these devices, we researched each manufacturer’s website and then asked the companies two key questions: First, how many empty-to-full recharges—or “cycles”—might it take for the product’s battery to reach capacity drops to 80 percent? (Batteries tend to degrade quickly after that point.) Second, what options does the owner have to repair or replace the battery in their device once it’s out of warranty?
For example, Bose said its popular QC noise-canceling headphones last 20 hours on a single charge and can take 500 full recharges. So for someone who used the headphones 5 days a week, we calculated that their headphones could start to break down after 5 years — without an official service option to replace the battery.
Several manufacturers declined to share battery cycle counts. We also took into account our own experience with the products and published reports from other reviewers and users.