How many hours is the battery life?
The Pentax Optio WG-1 camera seems to draw down the battery even with the camera turned off. The D-L192 is a relatively small battery, so I have found that if I remove the battery from the camera, it holds it's charge for at least 2 or 3 weeks (Probably more), but if I leave it in the camera it runs down in three or four days (or sooner) without use.
That being said, I have never run down the battery while actually using the camera. I feel confident that one could shoot three or four hundred images over the course of a half to full day. I personally have shot nearly 200 images over a two hour hike.
I bought this camera/battery to shoot macro images because it will focus down to about 5mm and has the LEDs around the lens to illuminate the subject when shooting extreme closeups. Since the camera does not shoot RAW, it is my 3rd or 4th choice for other kinds of photography. I bought the spare battery thinking I would use it the same way I do my SLR batteries; when I notice the battery is close to discharged, I charge the the next one. That doesn't work due to the battery going flat in the camera.
Note that Canon at least, recommends that their batteries be stored discharged. My Canon batteries typically are in the camera for a month or two shooting 6 or 7 hundred stills. This is why I wait to charge the battery until it is needed. Video depletes the battery sooner of course.
So, either charge the battery before use, or remove it when the camera is not in use. The down side is that you have to set the date/time every time you put the battery in, but that is very simple to do. Other than that, the camera/battery combination works very well.
I had to include the camera information because I don't know if this battery is used in other Pentax cameras that don't run down the battery when not in use. Or perhaps my WG-1 is defective, I don't know.