AOLIKES 1000mAh Replacement Battery for Sennheiser PXC 550 II Momentum 4 Wireless Bluetooth Headphones...

I write this 22 months after installing this battery, headphones were used only used a couple of times per week for about 10 months then a few times a month for the following year, the battery is completely worn out and I'm back on ZeeBooth now looking for a replacement.

So far so good ....the black and red needed to switch around before plug in ....

Before buying this battery, I read the reviews, and when I read about how their battery came improperly wired, I shrugged it off thinking the reviewer just got a defective battery. Nope, they were right, my battery also came wired improperly. Now I was able to fix it myself using some tweezers and trying to lift whatever was holding the wires to the connector, but I'm surprised it was done intentionally. After rewiring the battery and plugging it in, everything else went smoothly. They fit into the headphones just fine, they charge just fine, and my headphones works like normal. And yes, I am using the original PXC 550s. Just be sure that when you're using these batteries on your headphones, that the black wire comes first on the very ridged side, next comes the yellow wire, and the red wire should be last. 3 stars because the way these batteries come wired can be a huge risk for people who are following a tutorial that uses a different brand of replacement batteries, who can end up risking breaking their headphones or whatnot. In fact, I would've made the same mistake if it wasn't for Austin's review. Good Luck! And thanks to A. Austin for warning me from possibly shorting my headphones.

Battery was down to where it wouldn't make it through a work day, this was an easy replacement. I just needed to peel off the cover on the left earpiece, remove the 4 pieces of plastic over the screw holes, use a #0 Phillips bit to loosen the screws, pull up the driver and housing, then use a #00 Phillips to remove the screw on the little daughter board, and finally use a 2.5mm flat to pry up the battery from the glue and remove the 3 wire connector from the daughter board. Then stick the new battery to the glue, replace the #00 screw, reattach the driver and cover, and put the #0 screws back in. Finally I covered the screw holes with some kapton tape and reapplied the ear pad.

It's been a day in my Sennheiser Momentum 3's, and so far so good. Charges up and runs the headphones. Since I couldn't find any info about how to actually do the replacement on the 3's, here's a little bit of the process that I learned on the fly: - The battery is installed in the LEFT ear cup. I figured it would be the right since that's where you plug them in, but no, my battery was in the left cup. - The screws are small torx screws (I believe). I ended up using a T6 tip on my screwdriver at least. - My original battery had actually started bloating, which explains why it could only hold like an hour of charge near the end there. - I honestly thought I had broken something while I was attempting to replace the battery. Everything's packed in there a little loosely, so just be careful when you're going through the process. - Generally, I followed the instructions of the Sennheiser Momentum 2 battery replacement video. The steps are pretty much the same.