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When earbuds’ tiny lithium-ion batteries die, they can’t be replaced.
By guest author Nicole Nguyen from the Wall Street Journal
March 19, 2023
AirPods are a daily fixture in my life. I’ve recommended nearly every model of the wireless, portable and easy-pairing earbuds from their start. But Apple’s AAPL -0.55%decrease; red down pointing triangle market-leading earbuds, along with most other competing Bluetooth buds, have a big problem: tiny, irreplaceable batteries.
I have the first-generation AirPods Pro and, after about three years of constant calls, music and podcast playing, I can use them for less than an hour before the “womp womp” low-battery sound plays.
Hundreds of millions of these wireless in-ear sets are sold every year, with AirPods and AirPods Pro being the most popular, according to analytics firm Counterpoint Research. Their lithium-ion batteries—similar to what powers smartphones and other electronics—degrade over time. Because earbuds are so small, their batteries tend to die faster, typically within a few years, and there’s no easy way to replace them.
Some day, your buds will end up in a drawer, recycle bin or, worse, landfill. AirPods are one of the many tech products we buy each year that die well before we want them to.
What about doing a repair yourself? Battery researchers I spoke to say you shouldn’t tinker with them, for safety reasons. And while there are alternative technologies that could power our devices for decades without needing to be replaced, they are a long way off and come with trade-offs that might deter companies from adopting them.
Caution: Fire Hazard
Most headphone makers don’t provide instructions on how to replace batteries in their earbuds or sell the batteries needed to perform the repair.
Apple offers AirPod battery service for all models no longer under warranty at $49 a bud, plus another $49 for the case. It’s pricey because it’s effectively a new pair, not a repair. “We will replace the user’s AirPod and send the previous one to a best-in-class recycler for responsible handling,” an Apple spokeswoman said.
And while Apple offers self-service repair for iPhones and Macs, it doesn’t provide DIY manuals or replacement parts for AirPods.
I wouldn’t attempt a battery swap myself, even if I could. The community repair website iFixit rated the original Pros a zero out of 10 on repairability because the internals are glued together and the battery is soldered down. A battery swap would effectively break the Pros.
Not all earbuds are as impenetrable as the AirPods. Gio Cerdena replaced the battery on Sony’s WF-1000XM3 himself after the buds, originally purchased in January 2020, stopped holding their charge. The model is bulkier than most, hence the relatively simple repair. Mr. Cerdena, an audio engineer based in Manila, said he watched a YouTube tutorial and sourced the replacement batteries online for $24. He said it took six minutes with a screwdriver in hand and a credit card as a prying tool.
Sony’s newer XM4 buds aren’t as repairable. A Sony representative declined to comment on DIY repairs.
Repair at your own risk. Batteries are the least safe parts of electronics. If they are punctured or short circuit, they can create a self-sustaining fire. In New York, much bigger e-bike batteries caused hundreds of dangerous fires last year.
Tightly glued parts make repair tougher, but there’s a reason behind it. The seal created by glue also prevents dust and water from damaging the battery, said Zhengyu Ju, a Ph.D. candidate researching batteries at the University of Texas at Austin.
The Limited Life of Batteries
Each time you use batteries, they decay a little bit. Researchers and technicians measure the decay rate based on charge cycles, that is, every time you use 100% of your battery. (This could be 30 % one day and 70 % the next.)
When a battery can only hold 80 % of its original capacity, it’s considered a dud. Apple says iPhones can go about 500 charge cycles before their batteries hit that threshold. For Macs, it can be 1000 charge cycles.
The company doesn’t share figures for its AirPods, however. Some analysts have pried the buds apart, and estimate that the type of battery used will reach 80% after about 500 charge cycles. If you’re running down your earbuds daily, that’s about a year and half’s worth of battery.
It isn’t a steady decay over time, however. Batteries age fast at first, then slowly, and then fast again toward the end of their lives, said Anna Stefanopoulou, a professor of mechanical engineering at the University of Michigan. Fast charging and wireless charging can degrade batteries more quickly, she added. Apple’s Optimized Battery Charging setting can help here. When enabled, AirPods will charge more slowly until you need them, based on your charging habits.
New lithium-ion battery technology, using iron or titanate as a component, can last longer than current batteries. The trade-off is that both kinds hold less energy in the same amount of space, meaning potentially worse day-to-day battery life.
The titanate variety can last at least 15,000 cycles, said Charlie Welch, chief executive of ZapBatt, a company that makes lithium-titanate batteries. “Companies, and a lot of people, have the idea that batteries are disposable. In the future, it should be a more circular economy,” he added. “Batteries should last so long that they could move between products.
One startup, the Swap Club, is embracing that circular model. You can trade in your old AirPods and receive preowned AirPods with new batteries starting at $50 a pair. It sounds like an earwax fiasco waiting to happen, but the company’s co-founder, Emily Alpert, says the Pods are brushed and sterilized. Ms. Alpert said the new batteries have slightly longer life than the originals.
The replacement process is done by robots and manual labor, she said. It’s so challenging because of the size of the buds, she added, that many trade-in units still end up being sacrificed to the recycle bin.
The Swap Club doesn’t offer AirPod Pros or third-generation AirPods yet. Ms. Alpert said the newer earbuds’ water resistance is hard to maintain after a battery swap. That’s the trade-off of these tiny gadgets. To be durable, they need to be water-resistant. To live in our ears, they need small batteries. Both make replacing batteries difficult.
We could always forfeit the convenience and go back to wired headphones. Apparently the cool kids are doing it.