2X Pack Z55H 3.85V 70mAh Battery Replacement for Sony WF1000XM4 WF-1000XM4 Industry Leading Noise Canceling Truly Wireless Earbud Headphones Battery+ Tools

Excellent little replacement kit! Comes with 2 batteries, glue, and all the tools you need (and then some). Process took about 30 minutes, now my headset is charging & connected! We'll have to see about battery life, but looks normal so far. Heads-up, some of the steps are very intricate. I followed the iFixit guide and used one of those magnifying glass lamps.

Effective and (relatively) easy to use replacement kit for the Sony WF-1000XM4.You may need to warm the earbuds up - and if you do, be cautious about the touch controls and the ear-tip connection. I've slightly deformed either on multiple sets, and while this does not affect the performance, it's something that could otherwise be avoided.I can't speak for this specific kit's longevity, but the first kit I purchased that was a mirror of this kit lasted ~1.5y before needing to be redone. Still - an inexpensive option vs purchasing a new set of earbuds.

Full transparency, I'm only 2 weeks or so into the swapping out of the batteries and I haven't had a chance to use the earbuds heavily since then. I'll update accordingly if things change.Pros:- Price is inexpensive- The kit they send to help with the replacement is a great touch. I saved the kit after I was done and plan on using it for other things in the future. Nice bonus.- About 2-3 weeks in, the batteries seem to be working very well and have restored the right earbud to as it was from the factory. Time will tell how long they hold up, but I'm optimistic.Cons:- None regarding the batteries and kit that were part of this purchase.What to watch out for:- Don't apply too much heat to the earbud you want to disassemble. Turning the earbud in your fingers while applying heat from a heat gun or hair dryer should do the trick. Apply even heat for 10-15 seconds and see if you can pop the housing apart.- I used a paper towel for cushion, applied pressure via a pair of pliers with the paper towel under the teeth of the pliers, and the case started to separate perfectly. Please use very little force when attempting to separate the halves this way as too much pressure could damage the earbud or mar the plastic surface.- When working on the replacement, be careful not to damage any of the ribbon cables inside the earbud.- To separate the circuit board from the top of the battery, I applied heat very briefly, followed by a back-and-forth motion with the included guitar pick looking tool until the circuit board was free from the top of the battery.- Removing the battery can be a bit difficult as it has a type of glue that helps keep it secure. Try to work around the edges of the OEM battery to fee it from this glue. You could also apply heat in short intervals until it loosens as well.- Make sure you drop the new battery into the earbud with the correct polarity facing upwards.- Reassemble in the reverse and you should be good to go. Charge the earbud(s) and test things out.I was a victim of the bad batch of batteries that Sony put into their earlier production of the WF-1000XM4 earbuds. After about 2 years of occasional use, and a firmware update in mid to late 2024, my right earbud would never charge past 95% and when in use, the right earbud battery would maybe last 30 minutes. I was less than pleased after having spent a considerable amount on these earbuds about 2 years or so ago from the time this started happening. I lived with it, opting to use my over the ear headphones for my long flights and didn't think much of it, other than vowing to never give Sony another chance on earbuds, I love their over the ear noise cancelling headphones though.In searching for this issue, I found this battery kit and decided to give it a try. What's the worst that could happen, the right side works 0 minutes versus 30 minutes? I used a YouTube video for the disassembly, removal of OEM battery, installing the new battery, and reassembly. I used a Milwaukee heat gun, and the glue softened quickly but a hairdryer would work as well. Took about 5-10 minutes per earbud, I replaced both so they would both have new batteries, and so far, all is working very well.

This kit has everything you need to replace the batteries in the Sony ear buds. I still had to use a pocket knife to open the case and it was a little challenging to work with such tiny pieces but the end result was worth it. I have given a new lease on life to my ear buds and the new batteries last all day long. Much cheaper than shelling out the cash for a new set. Same amazing sound as when they were new. Watch the "how to" videos closely and you'll be ok.

The batteries seem to work. Definitely recommend looking up a youtube video on how to replace the batteries before doing it. The tools included werent the best. I ended up using sturdier metal tweezers to get this install finished. After the install, the batteries charged up well and seem to be holding up.

The kit was ok, but one of the batteries is not lasting even an hour. I swear I did a return a week ago but it says I don’t have a QR code to return this junk. I’m pissed.

Item was Well packaged and is honestly working really wellFixed my battery issue right up..Long lasting life you can count on.

My wf-1000xm4 headphones were only lasting about 1.5 hours so I have these a try. The seller includes glue and some small tool to help you disassemble the earbuds.Pretty easy with a blow-dryer and a skinny pry tool or small flathead to get the casing apart. I used my own tools, but the included glue was nice to have to reassemble. Took about 10-15 mins total and headphones are back to 6+ hours of life!Make sure you bend down the little tab that touches the negative (up) side of the battery so it makes good contact after reassembly. I had to take one apart and do that because it wasn't getting power.