Rechargeable batteries are now available on the market, ion lithium battery and Z-power. The most common type of battery is the zinc-air battery. There is different brands of zinc-air batteries and it does make a difference what one you use.
Zinc-air batteries are air-activated, the sticker on them allows the batteries to remain inactive until it is removed. Once peeled from the back of the battery, oxygen will enter the battery and active it. For best performance from a zinc-air battery, wait about one minute after removing the sticker to fully activate before placing it in the hearing device. Replacing the sticker will not deactivate the battery, so once the sticker is removed, the battery will remain in an active state until the power is drained. The battery will last longer if you open the battery doors with you are not wearing them, DO NOT let the batteries touch each other (this cause trickle draining) and keep the stickers on them until ready to use.
If using zinc-air it is best to use the premium zinc-air battery. The most common and my personal favorite is Rayovac premium. Each manufacturer will rate their battery life on their favorite battery so, it is best to use the battery that is the same as the manufacture used for testing. You can find that information out by asking your hearing care provider. Hearing aids will perform best with that battery that was used for testing. Your hearing care provider most likely sell the same battery that your hearing aid manufacturer uses.
Z-power batteries I believe are on their way out. Some Manufacturer has stopped using them already. There has been some difficulty with the battery door. The good thing about z-power batteries is you can change it out for a regular batteries if you are unable to charge them. However, that is also the bad thing about them because some people end up throwing away the rechargeable battery instead of the zinc-air battery. The z-power batteries are a lot more expensive then the zinc-air but, they do last longer.
Ion lithium batteries are fairly new to hearing aids. The hearing aid manufacturers have made the changeability of them a little differently. Some manufacturers give you a closed case to charge them in and a few days charge in the case without having to plug it in. There are also extra charge bases that you can add to the charging case to get more day out of charging the battery before you need power. However, other manufacturer just has an overnight charge has to be plugged in to charge.
Donna R DeMarco, AAS, BC-HIS
Tinnitus Care Provider
Holding a Certificate from the International Hearing Society