Instruction: Given a question and the related document, and generate the answer to the question based on the information provided in the document.

Input:
Question: Need to know the best Bluetooth Adapter made by Sony for TV without AC adapter rather than battery operated.  Thx.
Document: I bought this because I work in a cube and I often want to listen to music to drown out the noise in the office. I hated being tethered to my computer by my headphones. This TINY adapter fits under my monitor, syncs up instantly with my headphones, and has a relatively long range (relative to the other bluetooth adapters I've tried). Also, because it plugs into the wall, no need to worry about when the battery is gonna die, cause it won't!
I bought this adapter so I could listen to my TV with bluetooth headphones. I returned the adapter for two reasons:  1)  The place in the back of the transmitter where the line out jack is plugged in was flimsy; I had to push the jack in really hard to form a connection. 2)  There was a sound lag that made watching TV while listening not enjoyable.This adapter is definitely "not ready for primetime".
I use this adapter on an older stereo system in the "receiver" mode. Plug the adapter into an AC outlet, plug the included cable from the unit into an available RCA type input on your old stereo receiver, and you can listen to your iPod from the comfort of anywhere in the same room. For my application, I also needed a Sony bluetooth transmitter to attach to the iPod as well, also sold at Amazon. The transmitter sends the iPod signal to the Sony adapter attached to the stereo.
We had not experienced any interference with any of our other bluetooth/wireless devices. I would definitely recommend this bluetooth adapter especially if you can get it for around $30. I have tried various other wireless transmitters for the iPod (i.e Belkin, iRock, no names) and I would have to say that the Sony bluetooth wireless transmitter is by far the best transmitter we have had. Then again it is bluetooth and doesn't have to be played over your FM radio.
REALLY sounds good. The second (Sony Bluetooth Wireless Transmitter for iPod) was designed to bring my 80 gig iPod back to life which became useless after getting the Droid X smart phone. Sony to Sony of course it works. IPod sounds good transmitting to the adapter. Also the phone which for the package probably is the best mate for this Bluetooth transmitter.
Very goood product.Two things:would be nice to have a battery build in inside.And this adapter needs to be placed preferably only on vertical position(like on the picture)Tried to double tape it on the back of my TV on horizontal position with straight signal from the transmitter - had a lot of interraptions and static.Other than that - perfect!
Excellent product. I paired it with a sony ericsson bluetooth ear phone (also purchased from amazon)  and it was good to go. Never dropped the signal or anything. I use it primarily to watch TV in my room without disturbing others.
I think it's ok but because the sony headphones don't work properly that ADORAMA sold to me and won't replace I don't know if it is the headphones or the sony adapter but the sound breaks up all the time don't buy
For TV listening, it would be better to buy a small distribition amplifier to feed multiple earpieces rather than use this product. I'm afraid that Sony put all their money into styling and not into engineering in this case.
He put it on his bedroom TV to listen at night... and now no one hear's it! It works well enough that we've ordered a second for the main TV.A bit of fair warning, this little life-saver only comes with the 3.5mm headphone jacks - to make it work with the TV you need a 3.5mm to L/R RCA adapter cable.
Answer: i have the Sony Two-Way Bluetooth Adapter for iPod and MP3 Players...i use it for my tv.  I am not aware that it has a battery.  I just leave it plugged in to the power cord.  It works great.