How do you ask for battery replacement?

Hi guys, I have a question.

I never owned a laptop before. I bought NP900X4C 15 months ago and it's screen cracked without any reason after a few months. Samsung replaced whole upper body including keyboard under warranty. When the new keyboard and screen came in, I realized that the laptop I bought was defective. It was very poor quality.

Currently the laptop has inefficient power usage of ~20% ( John Ratsey helped me to optimize it). I'm getting 3 hours of battery under light to moderate usage. I was wondering if I could replace the battery under warranty before it ends? If so, what should I say to convince them?

I actually called Samsung support, they said battery must last ~20 minutes for free replacement. Otherwise I have to pay for it. I can tell them the laptop was defective and have them inspect it, but they might hurt some other component. I've read many horror stories about them online (for the Samsung support in my country) and I want Samsung support to modify the laptop as least as possible.

 

When Samsung announced the 2012 Series 9 notebooks they claimed (see the attached press release):

Any request to have the battery replaced will need to show that the battery lost more than 20% of capacity and has done less than 1,500 charge cycles. You can check the current capacity by running the battery calibration utility in the BIOS.

Actual run time of battery will not provide the basis for a claim. Notebook (and many other) manufacturers like using the expression "up to" because the can then use the number obtained under the most favourable conditions (eg low brightness, no WiFi, reading a document) and if users only get half the run time they still fall with the "up to" definition.

John