Bose QuietComfort 35 Battery Replacement

Written By: Dominik Schnabelrauch

Comments: 50

Bose QuietComfort 35 Battery Replacement

Difficulty

Difficult

Steps

Time Required

45 minutes - 2 hours

Introduction

Use this guide to replace a worn out or dead battery in your Bose Quiet Comfort 35.

If your battery is swollen, take appropriate precautions. For your safety, discharge your battery below 25% before disassembling your headphones. This reduces the risk of a dangerous thermal event if the battery is accidentally damaged during the repair.

For this guide we recommend the use of a hairdryer or a heat gun. It’s manageable to disassemble your headphones with the use of an iOpener however the disassembly gets way more difficult.

You’ll need replacement adhesive and a soldering iron to loosen components during disassembly and and to reattach them when reassembling the device.

Your replacement battery may be a different size or capacity than your original battery. As far as we know all QuietComfort 35 replacement batteries will work with both the QuietComfort 35 I and QuietComfort 35 II.

Tools

Parts

Bose QuietComfort 35 Battery

Step 1

The earcup cushions of the Bose QC 35 are held in place by small plastic clips.
Grab the cushion of the left earcup and gently pull it to the center of the earcup to free it from the plastic clip holding it in place.
Repeat this procedure for all clips that hold the cushion in place.
Remove the left earcup cushion.

gibts irgendjemand der dies als service anbietet?

no name -

Step 2

Carefully peel off the protective cloth which covers the inside of the earcup.
The protective cloth is held in place by mild adhesive. If the cloth starts to rip during the removal, apply an heated iOpener to the cloth or use a hairdryer/heatgun at the lowest setting to loosen the adhesive.

Step 3

Remove the two Phillips #00 screws (6.2 mm length).

Step 4

Turn the headphones over.
Insert an opening pick into the gap between the plastic cover and the earcup frame.
Use the opening pick to pry up the plastic cover of the left earcup.
Remove the plastic cover.

Step 5

To avoid melting the speaker diaphragm by exposing it to too much heat in the next steps we advise preparing a protection.
Cut a cardboard as shown in the pictures so it covers everything inside the earcup but the battery cover.
Place the cover inside the left earcup.

Step 6

Even with a heat protector in use we highly recommend to start with low heat to loosen the adhesive of the battery cover and to raise it slowly (maximum of 100°C) if the adhesive doesn't soften.
Do not aim your heat gun vertically onto the battery cover but only in a flat angle facing the straight edge of it.
Use your heat gun to loosen the adhesive underneath the edge of the battery cover.

This is absolutely futile. I have a rework station, and I set the blower to 99 C. I heated this edge for 5-10 minutes straight, which had no discernible effect on the glue. Harsh prying at the edge with a small screwdriver after heating didn't budge it.

Raunchy Butts -

Step 7

Avoid puncturing the battery during the following process. Do not use metal tools or excessive force when working near the battery.
Insert the edge of an opening tool underneath the bottom corner of the battery cover. This requires some force.

Step 8

Slide the opening tool along the edge of the battery cover to loosen the adhesive underneath and create a small gap.

Step 9

Insert the flat end of a spudger between the battery cover and the battery.
Avoid to use the spudger as a lever when working close to the battery.
Use to spudger to carefully separate the plastic cover from the earcup. Avoid excessive force to the battery.

What's that white part…I accidentally push it and it's bent down a little bit…is it gonna be a problem?…please help me

Buvisuru Bandara -

Step 10

Remove the plastic cover from the left earpiece.

Step 11

In the next step you will desolder the battery cables.
Use this picture as reference for resoldering during re-assembly or make your own photo if the cable order differs in your model.

The iFixit battery does not have a white wire, which the original does. In addition to red and black, it has a blue one.

Raunchy Butts -

Step 12

Use a soldering iron to desolder the three battery cables from the circuitboard.

I didn't feel comfortable soldering in such a tight space, so instead, I cut the wires tot he old battery leaving as long of a wire as possible, making sure to cut each wire individually so it wouldn't have any chance of shorting. Then I soldered the long ends of the wire with the long ends of the new battery. Capped it off with the black shrink wrap stuff.

abu hajar -

Step 13

Try not to deform or puncture the battery during the following removal process. Soft-shell lithium-ion batteries can leak dangerous chemicals, catch fire, or even explode if damaged.
Insert the flat end of a spudger between the battery and the battery well.
Carefully pry the battery out of its recess.
You might want to change the position of the spudger a couple of times during this process to avoid excessive force to a single point of the battery.

Step 14

Remove the battery.
Do not reinstall a damaged or deformed battery, as doing so is a potential safety hazard. Replace it with a new battery.
Before installing a new battery remove any remaining adhesive from the headphones, and clean the glued areas with isopropyl alcohol and a lint-free cloth.
Make sure the battery cables are long enough to solder them onto the circuit board before installing new adhesive into the battery well.

Hey, its circuit board not curcuit board.

TimedIn - 30/03/21

Really Bruno? Then I could say that your comment has also mistakes!:

"Hey, its circuit board not curcuit board." is not, it is: "Hey, it's circuit board, not curcuit board."

Thanks Dominik Schnabelrauch, Scott Head and Jeff Stephens for this guide.

Jesus Areso - 17/05/22

Waste of $37, headphones show the battery fault white and amber flashing light. I can only assume the blue wire replaces the white wire since the instructions didn’t mention the color difference.

WL270 -

Conclusion

If possible, turn on your device and test your repair before installing new adhesive and resealing.

To reassemble your device, follow these instructions in reverse order.

For optimal performance, calibrate your newly installed battery: Charge it to 100%, and keep charging it for at least two more hours. Then, use it until it shuts off due to low battery. Finally, charge it uninterrupted to 100%

Take your e-waste to an R2 or e-Stewards certified recycler.

Repair didn’t go as planned? Check out our Answers community for troubleshooting help.

Author

Dominik Schnabelrauch

Member since: 23/11/16

217902 Reputation

42 comments

спасибо ! будет полезно на будующее

Komar - 29/12/20

Hallo, tolle Beschreibung. Vielen Dank dafür.

kann man bei den Bose 700 NC auch den Akku tauschen ?

Würde mich sehr freuen, wenn das so wäre. Hat da jemand evtl bereits schon Erfahrungen gemacht. Könnte mir vorstellen, dass viele 700 NC jetzt auch in das Alter kommen, in dem der Akku schwach wird.

Jens Nußbaum - 16/03/21

Fk Bose for making it so difficult! They all care about the environment so much, don’t they?!

Batteries should be easily replaceable by any customer by themselves! Ear pads as well. Bose makes it harder so you would throw away your $300 headphones when battery dies. So much waste, plastic and other harmful stuff.

EU mandated to use USB-C on all devices to reduce the waste. Batteries are more harmful. They should make it mandatory for batteries to be user replaceable on tech like headphones. Manufacturers are making disposable headphones in purpose, obviously. Like AirPods and other similar earbuds. 18-24 months and you’re forced to throw them away. They should offer cheap battery replacement for AirPods and like earbuds as well. Maybe trade in deals. $70-$90 a bud isn’t cheap replacement.

Companies are lying about the love for the environment to make us buy more and add more harmful waste to it.

Usern@me -

Actually, you can buy the earpads separately, even from BOSE themselves. I’ve replaced mine 3 or 4 times already and it’s pretty straight forward

Florian Wendelborn -

Thanks. Replaced my bose qc35 headphone battery. Works perfectly!

Thomas Maher -

Wastage and ‘the environment’ are not quite the same thing. Most, if not all, of the material used to make the device is recyclable. It’s not an issue of damage to the environment for companies to make it difficult, or really, to not make it easy to replace a battery. You’ll find many companies do this in order to make their devices more water-resistant and dust-resistant. It’s not just because the big bad rich guys hate the planet.

If you’ve an issue with waste, contribute your waste to recycling. It’s your fault, not the company who made the product’s fault, if you don’t.

Great guide.

Harry Grade -

Of course it is. Recycling needs energy. And recycling needs to seperate all the parts and composites. If you really think this earphone can get completly recycled you also think the the Santa Claus who brought this to you is real. Just use Google to see where all this electronic parts are “getting recycled”. Poorest African childs are burning it to get at least the rare materials of it for a tiny bit of money. Leave your beautyful and peaceful bubble where for every problem comes a great technological solution.

Felix Kallenbach -

"its your fault the product is wasteful, not the company's". oh wonderful, a corporate stooge.

never mind the fact that even if all parts are recyclable, theyre often too uneconomical for anyone to bother. or that companies specifically design for them to poorly repairable, which means theyll end up being thrown away or be damaged while trying to do so.

its reuse, reduce, and then recycle.

and recycling your tech is hardly a solution when the battery needs replacing. what an absolutely braindead take.

SBN - 28/04/22

Sir do you have tutorial to repair bose quitecomfort earbuds with left side not working? thank you

densus88 densus89 -

Hi! Is this process needed to be done only for the left ear?

Andrei Verdes -

Hi Andrei,

if you want to replace the battery there is only one in the left side of the headphones you need to replace.

Dominik Schnabelrauch - 07/03/22

that's really important to know as the right ear as well has a shut glued battery compartment.

Florian -

Dit ziet er lastig uit, dat gaat mij niet lukken. Weet iemand een bedrijf die dit doet? Bvd, Hans

Hans Wiltink -

Did you find someone to fix your headphones for you?

David V. -

Unfortunately the battery is not available from reputable sources. I found a seller on ebay which sells compatible batteries from the brand vhbw. They look decent, however are available in 350mAh and 600mAh. If I see it correctly on the pictures above, the original battery has 495mAh.

Does anyone have a clue if those are legit and I can just use the 600mAh type?

Florian -

I just installed the 600mAh from vhbw. It works fine so far.

350mAh, 495mAh and 600mAh are different capacities and the higher is better. What's important is the voltage (3.7V) which should not differ too much.

If vhbw is not lying on its numbers, with the 600mAh you should get more music on a single charge than with the original battery, that's it 😉

Quentin H. - 29/04/22

Centralsound.co carries the battery

Michael H -

I just installed the 600mAh from vhbw. It works fine so far.

350mAh, 495mAh and 600mAh are different capacities and the higher is better. What's important is the voltage (3.7V) which should not differ too much.

If vhbw is not lying on its numbers, you should get more music on a single charge than with the original battery, that's it 😉

Quentin H. -

I didn't need to use any heat to lift the battery cover.

I used a thin blade / knife to cut the adhesive between the lid and the headphones on the exposed sides and then managed to carefully pry it open with my fingers.

The adhesive, in my case, was a bit rubbery and thus not too difficult to remove.

Obviously, be very careful with sharp objects around batteries, as stated in the guide also.

To put it back on, I just cut a couple of very tiny pieces of double sided tape. We'll see if that holds up well.

Also, I was wondering if the glue is there to somehow protect the wearer in case the battery does break down and catch on fire.

And thus if you should glue the battery lid shut properly after replacing the battery. Any ideas?

Albert Einstein - 29/05/22

The glue maintains the airtight integrity of the speaker and enhances bass response and noise canceling. You MUST maintain the seal or else sound can leak out. You can get feedback squeal if it leaks where it shouldn't.

Peter Wilson -

I want to know how to do QC45

Please write about QC45

Ifixit is best!

woojae0128 -

So I surmise that the headphones come with one battery from factory. In the left cup. But there is space for anotherin the right ear cup... any reason i cant have a battery each side and double the life? I guess I'm the guinea pig..

DVS -

How are you going to run the wires over? you do realize there are 2 folding joints and then the headband to worry about?

abu hajar -

Thank you, this was extremely helpful! If anyone is struggling to soften the glue, be patient. Even if it seems like it isn't doing anything, the cap will lift much more easily if you evenly pre-heat the glue as described here. The rest was comparatively easy. Keep in mind that the battery is also glued to the bottom of the case, so be patient and persevere, it'll come off!

Chris -

OT: I use my BOSE 700 wired. Problem is I still have to charge them for NC and during charging they don't work. Is the a mod to charge and have NC at the same time? ??

Tom George -

There is a way that only developers of the headphones can use to run the headphones while they are still charging. It requires sending a special command I think over serial but you would need to know exactly the protocol used. But the product owners in their infinite wisdom decided against this option because it would be too confusing to the customer.

The only way is to somehow hunt down and make friends with a QA person at Bose who still has access to all the knowledge and hardware to actually enable and send that command.

source: I was there when they made that decision.

abu hajar -

Easier than I thought. I had never done soldering before.

Samuel -

Where can you find replacement #00 (6.2mm) screws (step 3)?

Jeff -

Cannibalize an old cell phone, or remote control, or other obsolete electronic waste. Maybe some small electronic device. Maybe use tape around the edges of the aluminum cap, if all else fails

Peter Wilson -

I'm step 3, what is the silver looking ribbon. My dog eat the top cushion, side ear muffs, and took off the silver looking ribbon. I'm able to hear sound and everything else appears to work. I can find replacement parts for everything except for the silver stuf. Anyone have an idea?

christopher a avery -

https://www.reddit.com/r/bose/comments/f...

David V. -

Has anyone had any luck with these instructions for the Bose AE2W? Can't find a guide but believe the design is fundamentally the same between these models with the exception of circuitry for noise cancellation, extra switches mics, etc.

Mine appear to have two allen shaped security headed screws in alongside a small Philips head.

George “G” Mullis -

I always test the voltage present at the battery wires to confirm that the battery is dead or not holding a charge. It's no fun to replace a good battery with a new one just to have a dead headphones in the end. Sometimes the charging port in the OTHER side or associated flexible circuit boards used as conductors fail.

Peter Wilson -

Thank you! It was easier than I thought :)

Peter -

J'ai remplacé la batterie d'origine SYNERGY AHB110520CPS, 495 mAh, 3.7Vdc, par une batterie vhbw de 600 mAh, elle fonctionne parfaitement.
https://www.amazon.fr/dp/B09L5H4JDH?psc=....
Conseil, éviter de chauffer la trappe de la batterie, il y a un risque d'endommager le haut parleur du casque, c'est plus long mais j'ai utilisé une spatule en acier et l'ai introduit sous la trappe puis j'ai fait levier. Ensuite je nettoie les traces de colle restant. Pour le remontage je colle avec Colle professionnelle B7000 en tube de 15ml et le tour est joué.

Jean-Claude MARIN -

Any suggestions on appropriate glue(s) to stick things back together? I would want to use two part plastic glues since that would bond them forever. But I don’t know what else is suitable

Aaron Lawrence -

%#*!^@, I meant would NOT want to use two part plastic glues…

Aaron Lawrence -

What glue/ adhesive should I use for this repair?

Spag Tortellini -

just some tips after i did this... if you are bad at soldering/ only have cheap soldering equipment, snip the old wires on old battery (negative first (black wire), closer to the battery to have as much available wire) and solder the new battery wires to it. it is much easier to solder 2 wires together (albeit very small and delicate, make sure to use general soldering practices like tinning the wire first, and using as least heat time as possible) than to risk damaging the pcb if you don't know what you're doing. also heat gun is not necessary, you can separate the battery panel with a razor if you're being careful. it is a rubber like adhesive, just go around the perimeter carefully and it will separate cleanly.

as someone else said, it is wise to clean up the old adhesive and use a light adhesive to glue the panel back in place to get a full seal.

wagwan yute - 22/12/23

First time I've seen a 'Red' Charging light on my Bose QC35's. Gonna fully charge then fully drain, hopefully, I'll have a longer battery life again. Great guide. When re-applying the battery cover, I heated it up sections then pressed and held it down to allow the original glue to set it shut again.

Martin Erskine -

Hello I replaced the battery in my bose quiet confort q35 II, but it still doesn't work, do you have any suggestion , it would upset me to throw them away since I also paid 32€ and lots of work to replace it. Thank you to anyone that would answer me with a good advice.

MrBean -

Hello, Perfect ;:)

Marcel Michalski -