The original CMOS battery into the ASUS Eee PC 1215B is a non-rechargeable lithium battery CR2032. The original package consist of the battery with two wires connected by welded metal plates. A plastic ring and an heat shrink tubing are used to prevent short circuits.
I replaced the exhausted battery, reusing the wires and the plastic ring. I removed the little metal plates, soldering the wires directly over the battery casing. Then I wrapped the battery with a new heat shring tube.