ICR22650 Battery Replacement for Onyx Studio 4, Onyx 4

This is the best duplicate of a original battery. This is my 3rd time replacing my battery in my studio 4 & this one is by far the closest to spec of the factory battery in the HK unit. The foam vibration damping material around the ends of the battery fit snug in the compartment inside the speaker & so far it’s holding a charge fairly well. I brought mine to the beach laying in direct sun & it played for about 5 hours on 1/2 volume. This is a 3000mah - 3 amp hour battery, so 5 hours of constant music in 100 degree weather is a pass in my book. Buy this one.

My battery in my studio 4 was completely fried, the speaker would not function unless plugged into the wall outlet. I decided to grab a replacement battery after browsing on Amazon and realized there were not many reviews on the batteries listed. This is a perfect replacement for the onyx studio 4. The disassembly of the speaker itself is not very hard to do by any means, especially with plenty of videos on how to do so on YouTube. The battery swap took less than 15 minutes total, and it worked flawlessly! This battery saved my speaker and made it fully functional again. Extremely happy with my purchase. Shipping took less than 2 days

Bottom line: fits perfectly with no rattles and the battery life seems like it's 20% more than the original battery. I have two Harman Kardon Onyx Studio 4 speakers and the battery on one of them stopped holding a charge. I replaced it and the charge on the new battery seems to last 20-25% more than the original battery in my second speaker. The second speaker is perhaps 2 years newer than the one whose battery I replaced and it seems to not have lost any of its charge longevity. Thus, I think it's a fair battery comparison and I recommend this battery replacement for the Studio 4.

Definitely thinner gauge wire than original and no wire insulation tape but worked great and holds a charge. Fairly easy install with some trim tools and a Phillips screwdriver. Definitely worth doing since my speaker wouldn’t hold a charge for more than 5 mins but would work while plugged in.

I reluctantly purchased this battery for the simple reason of just not wanting to spend all the money for the factory Harmon Kardon battery. The battery works great and last a long time and was a very simple installation. I definitely recommend this battery!

It works for 1 day and never get to recharge again 😡

I have very mixed feelings on this replacement battery. For positives.... The battery is the same size as the original and fit nice and snug in the speaker as expected...not loose or creating rattle or noise. As other reviews mention the wire gage is smaller than the original, but other than that it is fine. The replacement did not come with foam protective tape around the wires as the factory battery did. I peeled the foam tape off the factory battery and wrapped it around the new battery and it worked great.The battery charged just fine as the original did and powered up my speaker just fine. However, this is where the cons come in and bring with it my mixed feelings. While it works and the speaker plays fine, the play time is significantly reduced from the original battery. I bought two of these Onyx speakers at the same time. I often run them in stereo and party mode on the patio etc. After using the speaker on several occasions and running it through several charge cycles I set them both up to play in stereo mode so both were playing the same thing at the same time with the same volume level. After appx 90-120 minutes I took a screenshot of the battery levels reported in the Harmon Kardon app. Speaker 1 is the new battery and speaker 2 still has the original battery from 2018. Unfortunately, as can be seen the new battery is showing appx half the remaining capacity of the original battery. While not overly scientific, this is accurate and thus disappointing for sure.I only replaced this one battery as it was having issues driving the speaker properly without being plugged in. I definitely expected at least similar run time from the new battery considering the age of the original battery.Maybe I just got a bad unit....won't know without returning it and starting over again. I will continue to use it as is and update as needed if any changes occur. However, I will not be choosing this brand again when I need to replaced the battery in the second speaker.

Just a tad shorter than the original, but a snug fit. Not too difficult to install, but take your time. This is not a user-serviceable part really, so some skill is required.