Good advise but I normally put them in at 6am and usually have them on until 1-2 am (18-20 Hrs.)
So far so good, they have reached the shutdown point and charged right up again.
I think battery is fine, seems to likely have been left in an undercharged state for a long time and depleted even more to the point that the charger would not pick up and charge.
All good for now.
n
Thanks
Mike
Still looking for a battery source.
The battery in my Oticon OPN S is marked Z22.
The size and type is not yet recognized in Wiki.
The only Google reference I can find of the rechargeable Z22 Lithium-ion button cell battery is in a US patent…US9564654B2 - Rechargeable lithium ion button cell battery - Google Patents
The Patent says: “The capacity is found to be at 24 mAh at 5 mA discharge current, average voltage 3.7V to end voltage 2.75V, after being fully charged to 4.2V. Total energy is 89 mWh and volumetric energy density is 345 Wh/L. Remaining capacity at 80% of initial capacity is found after 600 to 1000 cycles typically at 800 cycles. Cycle regime is at 12 mA constant-current constant-voltage charge to 4.2V and discharge at 12 mA to 3.0V, 25 to 30 Celsius.”
And goes on to describe the Z22 size as diameter 7.8mm and 4.0mm high.
The inventors work at Zhuhai Zhi Li Battery Co Ltd (ZeniPower) Add: 7B, No.130, XingHua Road,
XiangZhou District, ZhuHai, GD519002, China.
I am sure one of you engineering types or other clever sleuths out there, can track down a source for this battery type. 
This Oticon video shows how to change it…but not where to get it!
The battery shown as “Oticon” is the Z22 from my OPN S.
Lloyds was able to help me.
https://lloydhearingaid.com/shopping/audiogram.asp?action=incomplete%20hearing%20test
Mike
Hello!
I bought on ebay an oticon opn s1 device that is used before. And the seller did not specify that the device is rechargeable. And it came with totally dead battery. I can’t even check is it functioning. Did you solve where to buy such a z22 battery?
As I understood it’s 3.7V. Did you measure the voltage of your?
The quick answer is no. I have not been able to source an alternative source for the Z22 battery.
The good news is that you can take your aid to any Oticon audiologist/distributor and they will either change the battery there or send it to Oticon for battery change.
I must say a very big thank you to @menglxs!
I bought a pair of Oticon OPN S on Ebay some time ago. On delivery, one of them immediately charged but the other gave out the dreaded triple Red flash of death. For the last 4 months I have been looking rather forlornly at that charger and the deadly triple flash trying to source a new battery to no avail.
So as a result of this thread, I had my son fabricate a device as suggested by @menglxs. My son had a battery tray that he had previously bought from some electronics shop and used some wires, a “chip clip” (as we in Oz call a plastic clamp for resealing an open bag of crisps), two screws and a quick solder.
I was a big nervous as to what would happen while clamping up the dead Li-ion battery. But we went ahead and switched on power from the 3 batteries wired in series for 60 seconds. Then we removed the battery replaced it in the HA and then tried it in the charger. Success as the charge light came on solid Red! And after a few hours solid Green to indicate fully charged! 
What a great forum this is; and how much I have learned from all of you!
Cheers and thanks. 
First sign of success!
Fully charged…back in business.
Thanks for sharing this! Can you keep us up to date maybe in a month or two on whether the revived battery still continues to be charged and functional for the duration it’s supposed to last in each charging cycle? Thanks.
Congratulations, happy DIY!
I have been successful, still working normally for almost a year now.
Still looking for aftermarket replacements though.
Mike
Thanks for the update. This is great news.
I own Ryobi battery-operated tools and have seen people do similar things to revive the dead un-rechargeable Lithium-ion batteries they have. Basically if they’re drained below a threshold level then the BMS assumes that they’re dead for good and won’t allow a recharge to take place. But if you “revive” the battery to above the threshold voltage by temporarily pumping enough current into it to bring it back from the dead (by applying a higher voltage) to get the BMS to accept charging it, then you may be able to revive it.
A HUGE thank you to all of you who’ve contributed to this thread! I have Oticons that I got in the spring of 2021 and last night, Nov 1, had my right HA do the same thing! So I took a 9V battery to bring my HA battery back to life. It’s currently charging and seems fine.
One year has gone by and this battery is still going strong without problems (now with another user).
In the last few months I have also brought three different Oticon More dead batteries back to life using the same device (I am now using 30 seconds rather than 60 seconds of zapping).
They are all working perfectly again and recharging as they should…thank you again @menglxs !
Be careful Rob…4.5 volts does the job. A 9V battery might be dangerous to hit a 3.7V Li-ion battery…over-voltage could lead to thermal runaway with resulting fire/explosion risk.
And Rob, a big welcome onboard the forum!
A follow up on this topic. I had to do it a few times afterwards, I would only get 12 hours with it. Then the last time, no dice! It would not charge. I took it in to the audiologist, and she did a reset by holding the volume down button for 5 to 6 seconds, then put it directly in the charger. It charged fine, and doesn’t seem to drain as quickly. So far, so good!
I heard from a forum member (@SpudGunner) who owns the More 1, who had his rechargeable Lithium-ion battery replaced under warranty, that his audi had to reset the More 1 via Genie 2 in order for the HAs to recognize that they have now received a new set of batteries in order for it to work properly.
Originally they gave him the OPN S rechargeable batteries mistakenly as replacement for his More batteries and it was not reset (the audi was on vacation so the receptionist didn’t know better) and it was still acting weird. After the audi got back, he reset the HAs to the new batteries but it was still acting weird. Then he realized that the receptionist doled out the wrong battery for the OPN S instead.
But after the new batteries specifically designed for the More were ordered and used as replacement, and the HAs were reset again, then everything is fine again so far.
I’m guessing that the HAs keep track of the batteries’ performance history and tell the charger how to charge accordingly. So by reviving your batteries with no reset, the HAs still remember them as having a lower capacity and probably only allow the charger to charge only up to that lower capacity. By resetting the HAs, they now think the batteries are freshly new so now the HAs probably start charging them to the full capacity.
@Volusiano: MrV once again gets top marks for his listening skills! The details of his summary are exactly right! Because I don’t possess his level of technical knowledge, I’m not able to speculate as to why the More devices take different batteries than the OPN S, but they apparently do. And it does seem logical to me that they would require a reset in Genie2 for the calibration of the battery meter and proper charging.
Even after the batteries were correctly installed by my audiologist, however, I was experiencing a funny issue: the HA LEDs would fail to turn green when the batteries were fully charged, but remained in their amber “charging” status. If I removed the devices from the charger and reinserted them into their charging cradles, however, the LEDs would immediately show green. My audiologist sent my devices and the charger back to Oticon for testing. They never did tell either me or my audiologist the results of their analysis, but my More1s have been easily lasting through my 18+ hour days with about 20% charge remaining by the time I turn in and put my aids back in the charger.
I am still not sure if the battery drains on it’s own or the aid is draining it while it is off.
I guess I could switch them back and forth to see if drains in one faster than the other, but don’t have the energy to watch them for six months at a time.
That’s about how long it takes to drain below chargeable with the charger.
I have new More’s and don’t use the S’s much, I’ve zapped 1 battery twice already, still going strong.
It seems to last the same as the other, 18 hrs or so with not too much streaming or phone calls.
Mike
I don’t see the difference between the More and S Batteries, they are visually the same and both 3.7v,
Could be a little higher capacity I guess.
I can’t find the exact specs or aftermarket batteries either.
Mike
I thought the WORST of my troubles would be rechargeable aids that die on a long, international flight (from hotel through airport, flight, Customs, yada yada).
But with my travel plans seemingly dependent on a HUGE variable outside my control, I now see almost a bigger issue with these rechargeables: the lithium ion battery charging less and less and less, till one fine day it won’t last beyond 60-seconds or a couple hours. Hm. That would make me uncomfy wondering when such a day would arrive. I’d likely end up ALWAYS having a pair of ordinary, size 13 battery aids as backup on my person.
On top of which I may never know if the issue is with the built-in battery, the charging station, HA firmware, or some combination of everything… The thought of being without my primary set of EARS for an open-ended amount of time is not appealing. I just went 3 weeks without my Phonak Marvels as they were shipped off for repair and all the Fed-X WEEK-LONG deliveries in between.
For CURRENT users of the NEWER rechargeables (Oticon More, Phonak Paradise) what are your experiences here? I ask cuz in the coming year I’ll likely investigate new aids. For some reason it seems all these are now rechargeables. Let me know if I have that wrong.
Almost 3 years on my OPN-S and 1 year on More and so far no rechargeable battery degradation.
Still getting 16-17 hrs. with a few hrs. of calls or streaming.
I do use my OPN-S’ as backup on late nights watching the tube until 2am.
