Be sure to remove the battery when plugged in cuz the heat will deteriorate the battery lifetime slowly.

Try Notebook Hardware Control: (I won't liable if got prob)
http://www.pbus-167.com/

Yup. It will increase the battery wear level (level of 'kong')
Glad could help.

I tot it's a feature called HYBRID GRAPHICS, only available for certain VAIO series.

From Microsoft Small Business Center

1. Power down all nonessential functions. Switch it off if you're not using it. Many business travelers already know that you don't want to take the DVD player for a spin on the plane, and that every time you hit "save" it can set thehard-drive whirring, which devours even more power. But users often also forget to turn off their wireless card when they are no longer using it but are still using their computer.

2. Stay out of extreme temperatures. The technology that powers you battery isn't terribly complicated. But it's important to understand a little bit about the chemistry behind batteries, and how that can affect your work. Specifically, temperatures can affect the performance of your battery. It's best to use (and especially charge) your batteries at room temperatures. Extreme conditions can drain your battery quickly. Also, avoid partial charges and use the battery until it is dead. Battery experts liken partial charges - and discharges - to eating a cup of lard every day. It significantly shortens your battery's life. Considering that a lithium-ion battery can explode if it's improperly used, it could also shorten your life.

3. Let your laptop do the saving. Not every computing device handles a power source in the same way. Some of the more sophisticated laptops, which are designed with business travelers in mind, are misers when it comes to using power. And that's a good thing - if you can remember to take advantage of it. Most users make the mistake of simply not choosing to use a product's built-in ability to conserve battery life. How do you harness your PC's built-in ability to save? Consult your user manual. Often, calibrating your laptop is as easy as double-clicking on the battery icon in the system tray.

4. Always, always carry a spare device that uses batteries. How obvious is that?