There are rechargeable hearing aid batteries available for hearing aids known as ACCU, which are manufactured by Power One.
Some hearing aid manufacturers include these with their hearing aids.
At this stage, the Australian distributor for Power One is not currently importing these into Australia due to practical and cost considerations.
Below is HABEX's assessment of rechargeable hearing aid batteries ...
The rechargeable battery for sizes 10, 13, 312 and 675 are charged using a "cardcharger" or "pencharger" which runs on rechargeable batteries.
You will need to recharge the batteries for the "pencharger" or "cardcharger" after recharging the rechargeable hearing aid batteries several times (depending on the charger type)!
Rechargeable Hearing Aid Batteries
Rechargeable batteries start with low capacity and only realise their full capacity after around 10 charging cycles. This represents a significant period of recharging and use before the battery will have supplied the same output as a zinc-air equivalent.
The table below shows the capacity in milliamp hours (mAh) of zinc-air batteries compared to the nickel-metal hydride (NiMH) rechargeable hearing aid battery.
Rechargeable NiMH battery
For example, the Power One ACCU 10 battery has a capacity of only 12mAh compared to 100mAh from the zinc-air equivalent. This means you would need to recharge the rechargeable hearing aid battery at least 9 times to get the equivalent capacity from zinc-air batteries. This makes the constant recharging inconvenient and time consuming for negligible benefit.
Rechargeable hearing aid batteries and chargers are also relatively expensive compared to zinc-air alternatives.
The cost of two size 10, 13 or 312 rechargeable hearing aid batteries is around AUD60.
There is also the cost of the charger, which is around AUD130.
Additionally, a "pencharger" or "cardcharger" must be purchased, along with batteries to run the charger you choose!
Finally, there is also the small hidden cost of electricity to recharge the rechargeable batteries which are used to recharge the hearing aid batteries!
For someone who changes the zinc-air battery in two hearing aids every 2 weeks, battery usage will be around 9 packets (6 batteries per packet) of zinc-air hearing aid batteries per year. This represents a fraction of the total cost of rechargeable equipment. It is our estimation that at least 4 to 5 years will pass before the higher costs of rechargeable equipment will be recovered. Assuming of course that the rechargeable batteries can survive that long, which is doubtful!
In addition to the inconvenience of continually recharging, it is our experience that the performance of rechargeable hearing aid batteries is significantly less compared to zinc-air batteries. This means a lot of recharging to achieve similar performance.
The high cost of the rechargeable batteries and chargers means that cost savings are negligible and take a long time to acheive.
From an environmental perspective, zinc-air batteries are very safe when disposed of correctly, compared to rechargeable batteries which are more likely to contain chemicals known to be harmful to the environment.
For the moment, zinc-air hearing aid batteries are considered to be most practical and cost effective, while offering superior performance without the ongoing requirement to recharge and turn over rechargeable batteries.