Hi Ayou,
Just in case you haven't added you under cabinet lights yet. here are some thingsd to consider. If you use battery operated lights make sure they are LED or they will drain the batteries. Same idea as when you leave the lights on in your car. You can get under cabinet lights that plug in. Really the best option is to have an qualified electrician install hard wired fixtures. They you have lots of options. Xenon, LED, halogens, and now there is a new LED tape that gives lots of light and is about 1/8" thick, Color can be tricky. Buy from a reputable lighting showroom. You can email if you have any questions. Easiest to reach me at work.
kat@mycrescentlighting.com