# What's with these strange battery instructions? **URL:** \ **Category:** Factual Questions\ **Created:** [January 29, 2020, 4:51pm UTC](https://boards.straightdope.com/t/whats-with-these-strange-battery-instructions/847170 "2020-01-29T16:51:01Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [January 29, 2020, 4:51pm UTC](https://boards.straightdope.com/t/whats-with-these-strange-battery-instructions/847170/1 "2020-01-29T16:51:01Z")
My hearing aid needs a new battery about once every three days. I recently purchased a different brand (Amazon Basics). On the packaging it says: > [@](#): > > Let a new battery sit un-tabbed for one minute before inserting into device. The tab they’re referring to is a small tab that’s is stuck to one surface (the positive pole) of the #10 battery. I’d always been told it was to make the tiny battery easier to handle. No prior brand has ever mentioned waiting after removing the tab before placing it into the device. Here are a [number](https://www.google.com/shopping/product/17172449029648953842?q=%2310+hearing+aid+battery&safe=off&client=firefox-b-1-d&sxsrf=ACYBGNSMLEyxMRuPu2ZkzsOj6ZMo8KH9Fg:1580316314700&biw=1280&bih=860&prds=epd:7248725494083064678,paur:ClkAsKraXyMkM-IwHwoUa0O9OUK32Ryd21Mb4PWTrIiH2qm9mxc_oHcZlJK_YwD003a8E3OZLzYfCBcEHSfYtMhTn8w8C_26TarhvPVCx-tn6CLpT_geO5-SLhIZAFPVH72um0iPoMQ7aqmBD4z1xhf00RoFDA,prmr:1&sa=X&ved=0ahUKEwiwrvOGoannAhVzhHIEHWlXDYoQ8gII2gM) of [brands](https://www.ebay.com/i/143344743732?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&itemid=143344743732&targetid=857040191190&device=c&mktype=pla&googleloc=9006330&poi=&campaignid=6469750549&mkgroupid=93041470030&rlsatarget=pla-857040191190&abcId=1141176&merchantid=101692899&gclid=CjwKCAiA98TxBRBtEiwAVRLqu2t85m15Z1R_kNjEnf_d2_mMuzYnRvVYN_DTxxZspxooz3ygJ3WWGhoCMsYQAvD_BwE) showing their[tabs.](https://www.google.com/shopping/product/13680095501844242106?q=%2310+hearing+aid+battery&safe=off&client=firefox-b-1-d&sxsrf=ACYBGNSMLEyxMRuPu2ZkzsOj6ZMo8KH9Fg:1580316314700&biw=1280&bih=860&prds=epd:601153857804568916,paur:ClkAsKraX603FBml9uoyfDK3gyDT9KS3Ru2RiF-aFJ5fMkksqOiJVmiZqAe-iq7atjc86DzlI7lBNg1KQdCcaNMutl2PUiVjqNjwp0yRq0qH38-RDs1JAjBAjBIZAFPVH71uO3rNDHYfvc0gdEwGxKgROpNxeA,prmr:1&sa=X&ved=0ahUKEwiwrvOGoannAhVzhHIEHWlXDYoQ8gIIrgM) Duracells have nice, long tabs and cool packages. What’s up here?😕 ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [January 29, 2020, 5:03pm UTC](https://boards.straightdope.com/t/whats-with-these-strange-battery-instructions/847170/2 "2020-01-29T17:03:25Z")
Hearing aid batteries are [zinc-air](https://en.wikipedia.org/wiki/Zinc%E2%80%93air_battery) batteries. They work by reacting zinc with oxygen from the air as a major part of the battery’s chemistry. The tab isn’t to make the battery easier to handle. It’s to keep air out of the battery. When you remove the tab, small holes let air into the battery, and the oxygen in the air starts the chemical reaction in the battery. If you put the battery immediately into the hearing aid then it won’t get as much oxygen into the battery cell and won’t last as long. ETA: I suspect that if you wait more like 3 to 5 minutes you might actually get a bit more life out of the battery. I don’t have hearing aids though so I haven’t personally tried it. ---
**Author:** ![Dickerman](https://avatars.discourse-cdn.com/v4/letter/d/8baadc/32.png) [@Dickerman](https://boards.straightdope.com/u/Dickerman)\ **Post date:** [January 29, 2020, 5:04pm UTC](https://boards.straightdope.com/t/whats-with-these-strange-battery-instructions/847170/3 "2020-01-29T17:04:54Z")
Those batteries require oxygen to work, and pulling off the tab allows oxygen in to interact with the chemicals. ---
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [January 29, 2020, 5:27pm UTC](https://boards.straightdope.com/t/whats-with-these-strange-battery-instructions/847170/4 "2020-01-29T17:27:34Z")
Wow. Thanks, I had no idea. > [@engineer\_comp\_geek](#): > > The tab isn’t to make the battery easier to handle. > [@](#): > > Featuring an extra-long tab, Duracell Hearing Aid batteries are simple to handle and install in your hearing aid device. 😃 Unintended, but hey. I used to pull the tab off after using the tab to place the battery into my aid. I’ll try waiting 5 minutes next battery. I was thinking I’d bought zinc-free batteries and they really sucked, turns out they were mercury-free. ---
**Author:** ![Shoeless](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/shoeless/32/7099_2.png) [@Shoeless](https://boards.straightdope.com/u/Shoeless)\ **Post date:** [January 29, 2020, 6:48pm UTC](https://boards.straightdope.com/t/whats-with-these-strange-battery-instructions/847170/5 "2020-01-29T18:48:03Z")
Wow, every three days? With my old pair the batteries would last well over a week. With my new pair, the batteries only last five or six days, but I assume that’s because they are in constant communication via Bluetooth with the phone app. ---
**Author:** ![Limmin](https://avatars.discourse-cdn.com/v4/letter/l/f04885/32.png) [@Limmin](https://boards.straightdope.com/u/Limmin)\ **Post date:** [January 29, 2020, 6:56pm UTC](https://boards.straightdope.com/t/whats-with-these-strange-battery-instructions/847170/6 "2020-01-29T18:56:18Z")
I just replaced my son’s watch battery, type CR3025. There was a sticker on the side, which I had to peel off. Could this also be a zinc-air battery? I didn’t read the instructions, but I think it must have sat on the desk about a minute before I put it into the watch and sealed it up… Meanwhile, a similar battery sat, with its sticker on it, in a kitchen shelf for a few years, and did not work when I put it into the watch. I thought the battery just ran itself down, but now I’m suspecting it’s the lack of oxygen to get the battery started…? ETA: Apparently it was an Energizer CR2025, not 3025. Their website says it’s a “lithium coin” type. Oh well. ---
**Author:** ![mixdenny](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mixdenny/32/2962_2.png) [@mixdenny](https://boards.straightdope.com/u/mixdenny)\ **Post date:** [January 29, 2020, 7:09pm UTC](https://boards.straightdope.com/t/whats-with-these-strange-battery-instructions/847170/7 "2020-01-29T19:09:30Z")
I thought the sticker on the coin series was just to prevent accidental shorting. Dennis ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [January 29, 2020, 7:52pm UTC](https://boards.straightdope.com/t/whats-with-these-strange-battery-instructions/847170/8 "2020-01-29T19:52:03Z")
If it’s a zinc-air battery, there will be a little hole in the battery case under the sticker. Other types of batteries will not have a hole in them. ---
**Author:** ![Steven\_Maven](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/steven_maven/32/3272_2.png) [@Steven\_Maven](https://boards.straightdope.com/u/Steven_Maven)\ **Post date:** [February 6, 2020, 6:19pm UTC](https://boards.straightdope.com/t/whats-with-these-strange-battery-instructions/847170/9 "2020-02-06T18:19:26Z")
> [@engineer\_comp\_geek](#): > > When you remove the tab, small holes let air into the battery, and the oxygen in the air starts the chemical reaction in the battery. If you put the battery immediately into the hearing aid then it won’t get as much oxygen into the battery cell and won’t last as long. Thanks for the explanation. I’ve been wearing hearing aids for about 8 years, but never noticed this instruction until December 2019. Previously, my batteries lasted about a week. Since I’ve been waiting, there has been no difference. Go figure. > [@kayaker](#): > > My hearing aid needs a new battery about once every three days. That seems very short. Is it possible that you don’t open the battery door overnight? (No offense intended.) > [@kayaker](#): > > I recently purchased a different brand (Amazon Basics). I haven’t noticed any difference in life by brand. The best price I’ve seen is Walgreens generic. (I haven’t checked Amazon.) I wait until they’re on sale “buy one, get one half off,” or occasionally “buy one, get one free.” ---
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [February 6, 2020, 6:31pm UTC](https://boards.straightdope.com/t/whats-with-these-strange-battery-instructions/847170/10 "2020-02-06T18:31:56Z")
> [@Steven\_Maven](#): > > That seems very short. Is it possible that you don’t open the battery door overnight? (No offense intended.) I used to remove my hearing aid any time I didn’t absolutely need it in, then the retrieval wand broke off. Since then I’ve been using hemostats to remove it, so I leave it in from 8 am to 11 pm. Three days is average life for me. I may rarely screw up and leave it on overnight. > [@](#): > > I haven’t noticed any difference in life by brand. The best price I’ve seen is Walgreens generic. (I haven’t checked Amazon.) I wait until they’re on sale “buy one, get one half off,” or occasionally “buy one, get one free.” I bought one package of “green” batteries (specifically mercury free) and they died quicker than my usual batteries. ---
**Author:** ![Kovitlac](https://avatars.discourse-cdn.com/v4/letter/k/2bfe46/32.png) [@Kovitlac](https://boards.straightdope.com/u/Kovitlac)\ **Post date:** [February 6, 2020, 6:58pm UTC](https://boards.straightdope.com/t/whats-with-these-strange-battery-instructions/847170/11 "2020-02-06T18:58:57Z")
I don’t have anything to contribute to the thread, but I do want to say that I love learning something new every day. In this case, how a specific type of battery works! ---
**Author:** ![thelurkinghorror](https://avatars.discourse-cdn.com/v4/letter/t/7c8e57/32.png) [@thelurkinghorror](https://boards.straightdope.com/u/thelurkinghorror)\ **Post date:** [February 6, 2020, 9:38pm UTC](https://boards.straightdope.com/t/whats-with-these-strange-battery-instructions/847170/12 "2020-02-06T21:38:40Z")
> [@Limmin](#): > > I just replaced my son’s watch battery, type CR3025. There was a sticker on the side, which I had to peel off. Could this also be a zinc-air battery? I didn’t read the instructions, but I think it must have sat on the desk about a minute before I put it into the watch and sealed it up… > > Meanwhile, a similar battery sat, with its sticker on it, in a kitchen shelf for a few years, and did not work when I put it into the watch. I thought the battery just ran itself down, but now I’m suspecting it’s the lack of oxygen to get the battery started…? > > ETA: Apparently it was an Energizer CR2025, not 3025. Their website says it’s a “lithium coin” type. Oh well. C means lithium-manganese battery. R means round. Hearing aid batteries usually leave off the letter, but I think they’d be AR?