Many hearing aid users wonder if their devices are safe and whether the batteries contain heavy metals like lithium. As an audiologist, I have combined my professional experience with research to answer this important question.
Do Hearing Aid Batteries Contain Lithium?
Yes — most modern rechargeable hearing aids use lithium-ion batteries that do contain lithium. These should not be confused with traditional disposable zinc-air batteries, which do not contain lithium. While lithium-ion batteries are safe for daily use in hearing aids, they can be dangerous — even fatal — if swallowed.
Today, convenience often drives battery choice. Some users prefer disposable batteries for quick swaps, while others enjoy the ease of placing rechargeable hearing aids in a charger each night. But safety considerations, especially when heavy metals are involved, should not be overlooked.
Market Shift: 80% of Hearing Aids Now Use Lithium Batteries
Over 2 million hearing aids are sold annually in the United States. Prior to 2017, almost all used disposable zinc-air batteries without lithium. That changed when manufacturers like Phonak, Oticon, Unitron, Starkey, GN Resound, Widex, and Sivantos introduced lithium-ion rechargeable models.
Phonak’s first lithium-ion model, launched in 2017, quickly gained around 30% of their receiver-in-canal sales. While early adoption slowed due to design challenges like difficult power controls, improvements in subsequent releases have led to lithium-ion batteries capturing over 80% of the market today.
Are Lithium-ion Batteries Safe?
Lithium-ion hearing aid batteries are safe for daily use. They are sealed inside the hearing aid casing, minimizing the risk of accidental ingestion. However, if a hearing aid or battery is swallowed by a child, pet, or elderly adult, it can be life-threatening. For more details on this risk, see my article What to Do If Your Dog Ate Your Hearing Aid.
Manufacturers have designed hearing aids so that only professionals can replace the battery, further reducing accidental exposure.
What About the Bad Press Around Lithium Batteries?
Reports of lithium-ion batteries in smartphones catching fire made headlines in recent years, but these issues have not been observed in hearing aids. Since hearing aids cannot charge while in use, there’s no risk of overheating during wear. In fact, lithium-ion hearing aid batteries have an excellent safety record since their introduction.
Disadvantages of Lithium Hearing Aid Batteries
While lithium-ion batteries are convenient and safe, they are non-removable by users. If a battery fails, the hearing aid must be sent to the manufacturer for replacement. This is similar to how smartphones require professional service for battery changes.
Fortunately, most lithium-ion hearing aid batteries last years — often outliving the hearing aid itself. On average, hearing aids are replaced every 3–5 years, and most manufacturers automatically replace the battery during any repair service.
Hearing Aid Battery Types Comparison
Below is a quick comparison of the most common hearing aid battery types:
| Battery Type | Contains Lithium? | Replaceable by User? | Average Lifespan | Safety Considerations |
|---|---|---|---|---|
| Lithium-ion (Rechargeable) | Yes | No | 3–5 years | Safe in normal use, dangerous if swallowed |
| Zinc-air (Disposable) | No | Yes | 3–14 days | Mercury-free versions safe; still choking hazard |
| Silver-zinc (Rechargeable) | No | Yes | ~1 year | Performance issues reported in past models |
Related Questions
Do hearing aid batteries contain mercury? Rechargeable lithium-ion batteries do not contain mercury. Older zinc-air disposable batteries once contained trace mercury, but nearly all modern versions are labeled “Hg 0%” to indicate they are mercury-free.
Is there lead in hearing aid batteries? Zinc-air batteries may contain trace amounts of lead, but a single accidental ingestion is unlikely to be toxic. However, all batteries should be kept out of reach of children and pets.