Rechargeable versus battery hearing aids

@jim_lewis my only issue with rechargeable batteries is despite claims of 800 cycles for an iPhone (I wish ill see that) is that expecting 5 years out of a Li battery that you wear and charge nightly would mean 1,825 charge cycles. That’s a lot. If you could point me towards battery info that supports that I’d appreciate it as I haven’t seen that. My question wasn’t about whether that’s even achievable, but how easy will battery replacement be. If it’s simple, something your audi can do in house, then that’s a big plus. If it has to be sent back to the factory, I’d be curious on turnaround time. I think rechargeable HAs have a lot going for them, especially keeping the interior sealed up which should allow for better moisture protection.

As to cold temperatures, I was simply pointing out that all Li batteries will deliver less current. You will likely be recharging sooner than at warmer temps. I’m not sure your ear is enough to keep them warm. It’s true across the board so any prolonged use in cold temps will drain them faster. Granted, there may not be a ton of folks who are outside in cold weather for 8-12 hours a day, but for those who are, finding a way to protect them without interfering with performance may help get a few extra hours out of it before ready to place back on a charger.

I think the future is for rechargeables replacing button batteries on next gen HAs. It’s fine with me as the little button batteries have their drawbacks. But rechargeables aren’t without their own limitations which hopefully will be addressed over time.

They are not easily replaced (at least in general) and require being sent back to factory. I have heard that recent Oticons are changeable by audiologist, but have not confirmed. Cost for return to factory is in the neighborhood of $200-$300 if done out of warranty. However, if you send them back near end of 3 year warranty, you’re likely to get 6 years of use out of them, which is beyond what most (not all) people keep their hearing aids.

@eskie227 said:

As to cold temperatures, I was simply pointing out that all Li batteries will deliver less current.

This is true of ANY battery. In colder temperatures chemical reactions slow down and all batteries depend on chemical reactions to supply power.

In point of fact lithium ion batteries should actually perform a bit better in cold than the zinc-air button batteries.

Jim

@MDB said:

I have heard that recent Oticons are changeable by audiologist, but have not confirmed.

I can confirm that Oticon OPN S and More Lithium-Ion rechargeable batteries can be replaced in the office by the hearing care provider without sending the whole hearing aids in. Actually it just requires a little small pin head like that of a paper clip to open the battery door. Even the user can do it if they want (kinda like opening up the sim slot on an iPhone) if they have the right tool. But they still need to order the rechargeable batteries from the hearing care provider anyway. I don’t think the Oticon rechargeable Lithium-ion batteries are sold by third parties.

Any idea what price range is for audi to change one? (Or have there even been any out of warranty changes yet!)

It’s a bit of a mystery so far, maybe a member of this forum who’s an HCP can chime in.

But in this thread Oticon # 222 Li-Ion Battery for OPN S - #18 by Volusiano, @1628w9st said that he bought a pair of the replacement batteries from the HCP who sold him the OPN S for $40/pair.

For Oticon users, here is the skinny on dryers:
Drying your hearing aids using a Dri-Aid kit16

@eskie227 said:

That’s a lot. If you could point me towards battery info that supports that I’d appreciate it as I haven’t seen that.

Here’s some battery info on charging. There are some Li chemistry that have long lifespans but I think the kicker is that they don’t have high capacities. So in demanding applications, such as for phone batteries, they tend not to be used. I just chose the following two links out of a “random” search on Li chemistry battery cycle lifespan:

Long Life Cycle - Lithium Werks

LONG LIFE Lithium Werks Lithium Iron Phosphate Battery has a long cycle life. Traditionally, the cycle life of a battery is the number of cycles […]

Proper Care Extends Li-Ion Battery Life | Power Electronics

Also, BU-808: How to Prolong Lithium-based Batteries - Battery University2

The second link just above may be a site that is just aggregating info gleaned elsewhere. I notice that the first few figures that they offer in their web page text generate <404> Page Not Found errors but the web page seems to have a good rundown on factors affecting rechargeable Li battery lifespan.

In my initial spiel, I left out use and storage at elevated temperature as a major liability of rechargeable Li-ion batteries. Because of that, I’ve set 85 deg F as the upper limit of temperature at which I will wear my rechargeable HA’s for any extended period of time. If I get into the mode of getting new HA’s at Costco every three years, I’ll stop worrying about high temperature exposure and just let Costco refurbish my HA’s within the 3 year warranty period if I wear them outside while working in the yard at 107 deg F in Texas summer.

Is there a way to charge these batteries to keep as spares, and how long will they hold their charge without active use for emergencies?

The obvious thing is you can swap them with the main batteries to charge them up, then put back the main batteries when done.

No idea on how long they can hold their charge. But the thing about Lithium-ion batteries is that if you keep them fully charged at 100% for a long time without using them, it’ll be detrimental to battery shelf life. They’re happiest being at 50% state of charge for long term storage. Otherwise they’ll go bad prematurely if kept at full charge or kept nearly discharged all the times.

So keeping spare lithium-ion batteries is a bad idea.

One thing you can do is keep swapping them in and out -> alternate them. Meaning after the first set is fully charged, swap them and use the second set on day 2. Then the morning of day 3, swap again and use the first set on day 3. Then 2nd set on day 4, first set again on day 5, and so on. It’s still not ideal because your spare set will still sit around a whole day at 100% every other day. Again, not an ideal situation.

Pretty soon you’ll get tired of the hassle when you find out that most of the times, a set will last you through a whole day anyway. And even if they don’t, doing an short interim charge for 15-30 minutes to top it off by 12-25% in the middle of the day some time when you can is still less of a hassle than having to swap batteries n and out of the hearing aids every day. The battery door is not designed to be popped out and in easily and very frequently in the first place.

Apples and oranges, methinks. But your regimen and attitude towards it seems reasonable. The other measures suggested don’t seem that way - to me.

As I said, YMMV.

@SpudGunner said:

I’m certainly not going to be using a significant proportion of my waning years refigerating hearing devices and changing out batteries that were not designed to be thusly handled.

I know - you’re already pegged to devote most of your time to your cats and lovely dog. Not a minute to spare for anything else!

I used to spend about an hour a day in various aspects of taking care of a beloved old cat that was very enfeebled and needed a lot of help (plus about $1,000/yr taking care of the animal). Now that the cat is no more, my expanded personal time budget allows me to spend about 5 minutes a day doing what I described about only partially charging when I snack (like I go to the refrigerator to get a snack - 95% of the time I am doing something else - same as if I were brewing a cup of tea - might take 5 minutes to brew but I don’t do anything but start and stop the brewing - so the amount of time involved here is being greatly exaggerated by Mr. SpudGunner). And I don’t do the refrigeration bit with HA’s - only with watch and phone that are both moisture-resistant and have much higher heat capacities and hysteresis in cooling and heating.

But when I pay about $1500 this fall for an iPhone 13 Pro Max (or whatever it’ll be called) with 1 Tb storage, I want it to last 5 to 6 years. My brother-in-law had an expensive out-of-warranty iPhone that he took to an Apple Store to get the battery replaced for $80. They told him no-can-do, the battery pull tab was broken (he thinks the Apple Store broke it in trying to replace the battery), and they told him that his only option was to buy a new iPhone(!). He bought a $30 do-it-yourself kit, risked trashing the phone, and managed to replace the battery after several hours work (but he’s unsure how water-resistant it is now). My less than a few minutes a day hopefully will prolong the life of my future iPhone, avoid having to pay $1500 every 2 to 3 years to get a replacement, hopefully, and avoid screw ups like my brother-in-law experienced by trying my luck with an Apple Store battery replacement. (I’m trusting my brother-in-law straightforwardly related his Apple Store experience). And I can spend the extra $1500 to $3000 on something else (like an Nvidia RTX 3090 GPU with 24 Gb VRAM to support the double image in a VR headset at ~4K resolution).

BTW, for folks who are big on “just trash it and get something new,” I recommend watching David Attenborough’s “A Life on Our Planet.” You can stream it on Netflix. He created it as a life testament to his feelings about the future of the planet after a lifetime exploring the disappearing wild. He has some pretty sobering statistics. Something like 60% of all birds on earth are now industrially raised chickens. Don’t know how solid or accurate his figure is that 95% of the animal biomass on the planet is now humans or animals being raised to support humans and wild animals are just 5% of the biomass. He predicts we’re going to be able to celebrate being part and creators of a 6th great mass extinction event on earth if we keep on our present course. He’s pretty sharp for a 93-year-old geezer.

Attenborough’s bio: David Attenborough - Wikipedia

In 1936, Attenborough and his brother Richard attended a lecture by Grey Owl (Archibald Belaney) at De Montfort Hall, Leicester, and were influenced by his advocacy of conservation. According to Richard, David was “bowled over by the man’s determination to save the beaver, by his profound knowledge of the flora and fauna of the Canadian wilderness and by his warnings of ecological disaster should the delicate balance between them be destroyed. The idea that mankind was endangering nature by recklessly despoiling and plundering its riches was unheard of at the time, but it is one that has remained part of Dave’s own credo to this day.”

… WOW! it’s too hot for me in this kitchen! They’re just material things with finite (engineered so …) lifespans that we can do only so much to prolong.

Anyway, to each, their own. I have cats to look after!

I doubt anybody on here besides us cares, but some links you might find interesting. Regarding percent birds being chickens: How many birds are chickens? – Full Fact2
My take: As stated, not accurate, but if altered to biomass and including domestic fowl, pretty ballpark. Wild animals: Tricky depending on definitions (if fish are included really throws things off) https://www.pnas.org/content/115/25/6506
Undoubtedly humans have had a profound impact on the planet.
Your regimen seems like a fun game for you. Would question net overall benefit of refrigerating batteries (energy use in opening doors), but it makes sense that it could prolong battery life. My game is trying to see how low we can keep household electrical consumption. We average about 120KWH a month most of the time, with up to 200 KWH for August and September while others in our area are often using over 1000 KWH during those months. Cheers.