Montblanc MB01 - Battery Replacement

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g4lius @g4lius

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Posted: Aug 31, 2026

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Montblanc MB01 - Battery Replacement

I'm trying to replace the battery in a pair of Montblanc MB 01 over-ear ANC headphones (2020, discontinued). The cell is dead — about one hour of runtime against a rated 20, and it collapses from 75% to zero in one step. Montblanc no longer repairs them and won't supply parts. There is no teardown, guide or forum thread for this model anywhere I can find, including in Chinese, Japanese and Korean.

I've been careful and stopped rather than force anything. Here's what I've established.

Ear pad side (right cup). The pad comes off cleanly — it has its own plastic carrier ring that clips into the housing, no adhesive. Underneath is a black bezel carrying the regulatory markings: Model MB 01, Montblanc-Simplo GmbH, Made in China, INPUT 5Vdc 0.72A, FCC ID 2AENP-MB01, IC 20163-MB01, CMIIT ID 2019DJ11415. Around the bezel perimeter are eight or so openings, all identical rounded rectangles, evenly spaced — as far as I can tell these are all sockets for the pad's clips. I can find no screw heads anywhere on this face, including under raking light. Inside the bezel is the driver behind a fabric dust cover. The only central feature I can feel through the fabric is the driver's dome, so nothing structural there.

Outer face. A smooth silicone dome with the Montblanc emblem. No seam, no lip, no step I can feel with a fingernail anywhere around its edge. There's a pinhole mic port through the silicone itself, which suggests it's bonded and registered to a mic capsule behind it rather than being a removable cover.

Chrome band. Carries the buttons, USB-C, 3.5mm jack and another mic port. I tried gentle leverage here with a plastic pick and the metal deformed very slightly before anything released, so I stopped immediately.

So: no fasteners visible on any of the three surfaces, no seam that takes a pick, and thin polished trim that bends before it gives.

My questions:

Has anyone here ever opened one of these? Even a partial attempt, or a failed one, would be useful — I've found nothing at all online, and I'd rather learn from someone else's dead end than repeat it.
Does anyone recognise this chassis? The build is almost certainly ODM, so the same shell may exist under another brand with a documented teardown.
Is a bonded outer cup the likely construction here, and if so is this a heat-and-adhesive-cutter job rather than a pry job?
Am I missing an access route — under the yoke fitting, or through the headband attachment?

Thanks in advance to the community for the help! Those are not perfect but they feel super nice I would like to keep using them wirelessly.

Thanks, that's really helpful — and good to hear the driver side is still the likely route. Photos below.

1 — Driver and dust cover, close. The fabric across the acoustic opening with the printed R ring. One of the perimeter openings is visible at the edge for scale. (Serial number blanked.)

2 — Bezel edge and chrome band. Shows the relationship between the black bezel, the pale ring around it, and the polished band. The small oval in the chrome is a mic port.

3 — Bezel at a shallow angle. Best view of how the black bezel sits relative to the pale ring and the outer shell, and of the openings in profile.

4 — Bezel, full view. Regulatory markings, and four or five of the perimeter openings visible at once. This is the face where I can't find any screw heads — these openings are what I've been reading as pad clip sockets, all identical and evenly spaced.

5 — Outer face and chrome band. The silicone dome with no seam or lip I can detect, and the band carrying the buttons, USB-C and jack. Leverage here made the metal flex slightly, so I stopped.

Two additional points: The dust cover isn't moulded into the baffle — the fabric is soft and moves under a light touch. And looking at how it meets the black ring, it appears to be glued and sandwiched between that ring and the assembly underneath, with the ring trapping its outer edge.

If that's right, the black ring is a separate part rather than part of the housing, which would make it the way in.

Questions:

Does that read correctly to you — is the black ring a removable retaining piece with the dust cover captured under it?

If so, is it clipped from behind, glued, or both, and where would you start? I'd rather not lever blind with the diaphragm sitting right there.

Are all those perimeter openings really just pad clips, or have I misread one of them as a clip socket when it's actually a fastener well?

Happy to take more shots or measurements of anything specific.

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2 Comments

Hi!

You've done a really good initial job! The standard for basically all headphones is access through the driver side, and I would still bet on that the driver side is the correct access route.

Could you take a couple pictures in good light and update your question please? Then we can easier help guiding you further. Check out this guide for how to update a question with pictures.

I want to wait until I see the pictures to make further judgment, but preliminarily the insides are probably held with clips and/or glue, it is not super common, but a likely contender in this case. Then I'd second that the outer cover is held by clips/adhesive.

Add some pictures and we'll be sure to give a better answer.

Cheers

Aug 31, 2026 by MeekVixen

Hi again @g4lius!

Did you attempt opening the headphones?

I found the FCC filing for these headphones those files had some useful information for getting inside if you haven't managed to already. So I wrote a new answer further down.

Hope this takes you further!

Cheers

yesterdayOct 11, 2026 by MeekVixen

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2 Answers

Hi!

You've done a really good initial job! The standard for basically all headphones is access through the driver side, and I would still bet on that the driver side is the correct access route.

Could you take a couple pictures in good light and update your question please? Then we can easier help guiding you further. Check out this guide for how to update a question with pictures.

I want to wait until I see the pictures to make further judgment, but preliminarily the insides are probably held with clips and/or glue, it is not super common, but a likely contender in this case. Then I'd second that the outer cover is held by clips/adhesive.

Add some pictures and we'll be sure to give a better answer.

Cheers — MeekVixen
Hi again @g4lius!

Did you attempt opening the headphones?

I found the FCC filing for these headphones those files had some useful information for getting inside if you haven't managed to already. So I wrote a new answer further down.

Hope this takes you further!

Cheers — MeekVixen

MeekVixen @meekvixen Rep: 7.9k 21 10 55 · Answer 1 · 2026-10-11T17:05:30-07:00

Hi again!

I checked the FCC filings for these headphones (FCC ID: 2AENP-MB0) and can confirm and establish a couple of things. Particularly with the Internal Photos document that shows the headphones in various disassembled states and the ID Label/Location Info document.

Both sides are removable in some capacity.
- However, judging from the photos (which are not in great quality) I would like to guess you will not disassemble the headphones from the non-driver side as I think it looks like thread mounts, but it is hard to tell. See disassembly step 4 and 5 for supporting entering and methods for driver-side access.
We get a kind-of disassembly process, where the ear pads are removed, then the label-disc (along with the cloth cover), then the driver mounts. The driver mounts has what could be screw holes that are more visible later in the document.
- Looking through the ID Label/Location Info document, we see that they have a thin PET disc with the ID Labels. The Chinese on one side of the disc translates to adhesive, supporting that the disc is held onto the driver cloth with adhesive, which may extend to the driver mounts.
- For an image of the driver mounts with the label-disc removed, with potential screw holes, see Figure 4 further bellow. Red circles marks potential screw locations.

Caution: If possible, use plastic tools to prevent scratches. Metal tools will scratch the headphones.

Take lots of pictures while you work. Once you're done, upload those pictures and create a guide, this will help the next person who has the same issue.

I still believe in entry through the driver side.

The battery is located the left ear cup, on the non-driver side.

Turn off the headphones and unplug any cables.
Remove the ear pads. To become figure 1. (See figure 1 at the bottom of this text)
Remove the thin plastic disc with labels. To become fig. 2.
- I am not sure which method will work best, so I'll list the options. We do know that the plastic label disc is secured with adhesive to the cloth, the cloth likely also be secured with adhesive to the driver mount, but we cannot know. Please respond with what worked and with your findings, then we all will know :)
- Ways to remove the thin plastic disc:
  - Insert a thin object, e.g. a plastic pry tool or a plastic spudger, in the lip between the plastic disc and the driver mount and pry up the label-disc and the cloth. Try to remove the plastic disc along with the fabric. If plastic tools does not work, you may use a (dull) knife, a metal spudger, or something similar half-sharp object (caution: metal has a high risk of scratching the surrounding area!). Refer to Fig. 3, red lines mark the lip.
  - Try weakening the adhesive with IPA (Isopropyl Alcohol), for electronics 70%+ is good enough, but 90%+ is recommended and is much better. You can find this in most electronics stores. After applying IPA to the lip (refer to Fig. 3), then let it sit for half a minute and give it some more IPA. After that, refer to the aforementioned point of prying.
  - If neither above work, try adding heat to soften the adhesive and then repeat the prying. However, let the IPA evaporate fully first. You can use a hair-dryer or a heat-gun. Try applying the heat only to the label-disc and not the center of the headphones / the drivers. You probably want to protect the driver from the heat. If you have kapton tape, you can make a shield kapton tape or a shield of aluminum foil and then secure the aluminum foil shield with kapton tape (electrical tape will react badly with heat). Or try to be creative, you might be able to use ceramics (e.g. a mug or small plate) to block the air-path from the heat-gun towards the driver, as ceramics is heat resistant.
Remove the driver mounts with the drivers.
- From this point on there will be more and more guess work, as there are no detailed enough images of the internals.
- Before further, two cautions!
  - The orange piece on the left ear cup around the driver is an antenna. The antenna is thin and fragile!
  - The driver mounts (with the drivers) have multiple cables attached to the backside. When removing the screws, the driver mounts may no longer be supported, be careful to not rip off the thin cables! The non-driver covers of the headphone also has thin cables attached to them and might also not be supported once the screws are removed, be careful to not rip off the thin cables!
- Based on Figure 4, I believe the driver mounts (and along with drivers) are secured with screws, and I believe that these screws goes all the way through and holds on the non-driver covers too. I've marked Figure 4 with red circles, indicating where I believe the screws may be. Of course, in your case, unlike Fig. 4, the driver mounts are not yet removed from the headphones. There may be more screws that becomes obvious when you open the headphones, so let us know!
Remove the non-driver cover to expose the battery.
- I hope that step 4. will remove the screws securing the non-driver side of the headphones. You might need to pull them off (grab them with your hands). Otherwise, be creative and let us know the way!
Identify and replace the battery.
- The battery is located in the non-driver side of the left earcup (refer to Fig. 5).
- Unplug the battery. (I think it has a connector, but it may be soldered cables, if it is soldered cables, desolder the cables to remove the battery.)
- Remove the battery by pulling on it from all sides with light force. You may use plastic plastic tools, e.g. a credit card, a plastic spudger or a plastic pry tool, with light force.
  - The battery might be glued. If it is glued, and light force does not remove it, use Isoprpyl Alcohol to soften the adhesive, let it sit for a minute, and try again. You may use plastic tools, e.g. a credit card to try to pry off the battery, yes, sometimes it may require slight force, but not excessive. If the battery does not loosen, try with more IPA. Do not use metal tools as this may puncture the battery. Do not use heat as this can hazardly damage the battery.
- Identify and confirm the battery. In the FCC filings (refer to fig. 6), we can see model name, a 3.7 V battery, 4.2V is probably the rated maximum voltage. It has 730 mAh. You can look for the exact same battery with the same model, search in google, Ali Express, Ebay, Amazon, and whatever suites you for the model, you may also search for MontBlanc MB01 battery, a.s.o. The important part is that its a 3.7 V battery, and that size are close enough. Note, the battery in figure 6 could be a per-production model battery and may differ slightly from the battery you have in your headphones.
  - If you've found a replacement battery but is unsure if it is the right one, tag us in a comment with the listing and we'll help you out
- Once you have the replacement battery, replace the battery, do all of these steps in reverse order to reassemble your headphones.
  - You may need to glue back the replacement battery. You can use any glue you believe in.
  - For what glue to use to put back the cloth and the label-disc, I do not have a definite answer, but I gave some educated guesses in this answer: What glue to use for the mesh underneath the earpads?. It may or may not apply to you, do whatever you feel like.

I would love to hear how this went, and if you can clarify any of these steps. Feel free to reuse anything for a guide :)

Big good luck,

Cheers

All figures below, with the exception of figure 3 comes from the FCC filing of 2AENP-MB0, from Internal Photos document Report No. EP990601 "Photographs of EUT", revision 1.

Figure 1. Ear pads removed from the headphones.

Figure 2. The label-disc and cloth cover removed from the headphones, exposing the driver and driver mounts.

Figure 3. The lip between the driver mounts and the label-disc. Red lines marking the lip.

Figure 4. The driver mounts, with drivers. Red circles marking potential screw locations.

Figure 5. The headphone with the non-driver side removed, showing the battery in the left ear cup.

Figure 6. The battery with markings such as model, rating, voltage, and more

MeekVixen @meekvixen Rep: 7.9k 21 10 55 · Answer 2 · 2026-09-03T14:43:30-07:00

After finding some additional information I've written another answer with better explanations, images, and procedures. See the other answer by me in this thread for that.

This original answer is preserved as it is a good general thinking that may aid other people with other headphones seeking a similar answer.

Original Answer

Hi!

Thanks for the pictures, really well done!

I am by no means an expert on this topic, but by looking at the pictures I can tell for sure that he manufacturer had zero intent on you getting inside them.

So, do I think this is secured by clips? No I don't. Unless the whole white outer ring with the black ring on top (sandwiching the fabric) has a certain amount of play, I do not think this is secured by clips. If it were, then there should be an amount of play to allow you to remove the clips, not to mention it being an unconventional way of doing things. Sure, be sure to fiddle with it, try pulling and twisting everything just to be sure.

About the outer perimeter openings, I have no clue what they are for. But I doubt that they would be used to open the headphones, once again that would be a very unconventional way of doing things especially when there are much better, easier, and cheaper methods (i.e. screws). You can of course always take a flash light and see if you see anything fun inside of those holes.

I think you are to disassemble by the driver side. I think the outer ring is glued down. This is based on that there is no seemingly obvious other way to open the headphones. And, by looking through the attachment holes for the ear pads, there is a shiny textured surface that looks a lot like a kind of glue or adhesive. I would not remove the black ring that sandwiches the fabric, but aim to remove the white ring that the fabric and black ring is probably glued on.

There is a small lip between the white outer ring and the metal housing of the ear cups, that is where I would try prying the ear cups open (see the red line in the pictures below). You can make an attempt without any heat, without pushing hard, just to see if there is any results or any play (and would this be clips and not glue, this action would probably make you feel the difference). But more than likely you will require heat to soften the adhesive, and would then be able to separate the white ring from the metal housing, opening the ear cup. When opening the ear cups, be careful as the driver/element could be attached to the outer ring to not rip off any cables (I don't think this is the case, but better safe than sorry.). You may need to use some force when prying open the white outer plastic ring, but you should not require extreme force!

Whether you'll use a hair-dryer or a heat-gun, you'll probably want to protect the driver from the heat. If you have kapton tape, you can make a shield of aluminum foil, and then secure the aluminum foil shield with kapton tape as that tape is quite heat resistant (electrical tape will react badly with the heat), otherwise you might be able to secure the aluminum foil shield by jamming the ends in the holes for the ear pad clips. Otherwise, be creative! You could additionally use ceramic (e.g. a mug or a small plate) to block the air-path from the heat-gun towards the driver.

If you use metal tools, just be aware that they have a higher risk of scratching the chrome finish and the plastic, and it should be okay if you tried with sturdy plastic prying tools after having applied the heat.

I think that covers most of it. Of course, all of this is just my guesses, so you can only try to know if it works or not. Let us know how this went when you're done!

Comment any response or if you have any further questions!

Take lots of pictures while you work. Once you're done, upload those pictures and create a guide, this will help the next person who has the same issue.

Good luck in your endeavor!

Cheers,

Where I would try to separate the ear cups, marked with the red stroked line.

Headphone

Montblanc MB01 - Battery Replacement

Update (08/31/26)

2 Answers

What information this gives us

Recommended Disassembly Process

Disassembly Process:

Figures

Update October 2026

Original Answer

The different means inside

Disassembly Process

Images:

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