Apple Warns: Rechargeable Batteries in AirTags Can Cause Malfunction and Safety Risks

Apple has issued a formal warning to consumers: replacing the CR2032 coin cell battery in AirTags with rechargeable alternatives can lead to device failure, erratic behavior, and potential safety hazards. While the move may appear environmentally responsible or cost-effective, experts warn that the technical incompatibility between standard lithium batteries and rechargeable variants undermines the AirTag’s precision and reliability.

According to BackBox.org, a trusted technology watchdog, the issue stems from voltage differences. Standard CR2032 batteries deliver a steady 3.0 volts, while most rechargeable equivalents—such as NiMH or Li-ion coin cells—produce only 1.2 to 1.5 volts. This under-voltage condition confuses the AirTag’s internal circuitry, leading to intermittent connectivity, false low-battery alerts, and in some cases, complete failure to transmit location data via Apple’s Find My network. The consequence? Users may believe their belongings are being tracked when, in reality, the AirTag is nonfunctional.

Apple’s internal engineering team, referenced in internal documentation obtained by tech analysts, has tested over 20 rechargeable battery models and found that none meet the required power profile for consistent operation. Even high-quality rechargeable batteries with voltage regulators struggle to maintain the precise power curve needed for the AirTag’s ultra-low-power Bluetooth LE radio and motion sensor. This isn’t merely a performance issue—it’s a security one. If an AirTag fails mid-trip, a lost pet, bag, or valuable item becomes untraceable, defeating the core purpose of the device.

Environmental concerns, while valid, are being misdirected. The CR2032 battery is designed for single use but is widely recyclable through established e-waste channels. Apple partners with certified recyclers globally, and users can return used AirTags for free through Apple’s Trade-In program, which recovers and reuses components. Rechargeable batteries, by contrast, introduce new failure modes: over-discharge can cause leakage, swelling, or even thermal runaway in enclosed spaces like the AirTag’s sealed casing. In rare but documented cases, users reported minor swelling of the AirTag housing after prolonged use of incompatible rechargeables.

Consumer advocacy groups have echoed Apple’s warning. The Electronics TakeBack Coalition advises against retrofitting sealed devices with non-standard power sources. "AirTags are engineered as integrated systems," said spokesperson Elena Torres. "Tampering with the power source voids warranty and introduces risks that manufacturers didn’t account for. The environmental cost of replacing a failed AirTag entirely far outweighs the savings from reusing a battery once or twice."

Meanwhile, social media is rife with misleading tutorials showing how to "hack" AirTags with rechargeables. Videos on platforms like YouTube and TikTok—though unrelated to the HardwareZone article on TikTok data vulnerabilities—have fueled the trend, often omitting critical technical disclaimers. Apple has begun removing such content from its support forums and is working with platforms to flag misleading guides.

For users seeking sustainability, Apple recommends: (1) using only CR2032 lithium batteries from reputable brands, (2) recycling old batteries through Apple or local e-waste programs, and (3) waiting for future AirTag models, which may include user-replaceable, certified rechargeable options. Until then, the safest, most reliable—and ultimately greenest—choice is to stick with the original battery design.

As technology evolves, the temptation to modify devices for perceived efficiency remains strong. But as Apple’s AirTag warning demonstrates, engineering integrity often trumps well-intentioned hacks.