How to replace battery in Phonak Audeo M-50R

By the way, the new batteries I have installed in my Marvel M50-R are still working perfectly. Also, the next replacement will be a lot easyer

I am wondering if anybody did that… Let me know…

I bought used Marvel rechargeables so I will definitely be doing this. Is there any way to assess battery health quantitatively or is just subjective guesswork?

I think it’s just a matter of noticing that they no longer hold a charge for any length of time, battery health (SOC) can be viewed in the App I believe.

I agree with tenkan. You will note that the battery will loose charge more quickly until it will no longer charge. Then, the HA will show a steady red light when inserted in the charger.

Gtremblay; markismus. I took the first steps to ordering some batteries on Alibaba. Did you have to deal directly with the manufacturer? Is it any more complicated than buying on eBay?

You can buy “Samples” directly through Alibaba but I believe that they redirect you to the manufacturer site. It seems that the manufacturer prefer selling samples to a company instead to an individual…

Thanks for a very informative thread, a small pile of powdered carbon and a single drop of superglue makes a lovely conductive adhesive in my experience with other items try it on a cheap AAA battery.


Are your replacement batteries still working OK?
Do you get a full day out of a charge?


Still working as new. I get a full day charge.

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Has anyone found the battery on other websites? Shipping from Alibaba is very expensive

This looks like someone who has done the research should put together a group buy to reduce the unit cost.

I am not sure a group buy would be really advantageous. Here is my reasonning for buying 6 batteries at $55+6($3 each): $73. So it is approx $25/pair. Since a pair should be good for 800 recharges or 2.2 years. Then my 6 batteries should allow 6.6 years of use. After that period I believe I will buy a new pair of HA with new technology.

So I believe this a very low cost to revive a very expansive pair of HA that would be otherwise dead. Don’t you?

I guess that after thinking about it, I agree with you. The batteries in my Bolero m90 aids are in great condition, and while programming them, I found out they are still under warranty until February 22, 2024.

Also I suspect that the Li-ion batteries have a shelf life even if never installed in the hearing aids.

If you think about it as a unit cost, relative to the cost of the hearing aids, it really isn’t all that much.

I will keep the info on file just in case. Thanks for the technical presentation.

After reading this thread and discussing with @gtremblay, I decided to replace the batteries in my Phonak Paradise 90 HAs. I used the same procedure described in this thread but I cut open the battery case with an exacto knife.

Everything went well but it was stressful !

My hearing aids are now fully charged and working, I will monitor the charge in the next few days.

Thank you @gtremblay for this thread !


I have been searching online for the Zenipower Z23L which is the original battery used by Phonak. I cannot find a source for these anywhere. Anyone had any luck in that direction?

The only battery I was able to find is an M7854 from the supplier mentioned in this thread. Do you think a Z23L would be significantly different ?

No, I don’t think the Z23L would be any different. Just wondered if it might be cheaper to obtain.

I hear you, there’re not cheap but at 25$ US it’s still cheap to give a new life to my HAs. In fact, I bought 12 of these, more than will ever need ! :grimacing: