I also thought you’d be interested in the bit of ‘amateur’ research by a school student in the USA which tells us how to extend the life of hearing aid batteries, published on May 5, 2015. Batteries cost money and we need to get as much out of each and every one as we can.
Ethan Manuell is a grade 8 student at a school in Minnesota, USA. He wears a left hearing aid. He and his audiologist, Mary Meier Au.D, looked at the effect a wait time would have on hearing aid batteries, that is, the time lag between activating the battery by removing the protective sticky label from the back and placing the battery in the hearing aid. Activation occurs when oxygen is able to mix with zinc-oxide inside the battery. Ethan found that if users wait 5 minutes from the time they pull the sticker off, the battery can last 2-3 days longer, a pretty amazing find considering batteries usually last anywhere from 2-7 days, depending on how much power they are generating.