Laptop Recharge
PlayStation 3 controllers recharge using USB cords with a mini-USB connector on one end for the controller and a standard USB connector on the other for the recharging device. As long as you have a laptop with a free USB port, you can recharge your controller using that port. Although it's rarely practical, you can actually recharge a PS3 controller using a laptop and continue playing games on the PS3 with that controller. However, Sony designed the controller to work with the PS3 system only, so while you can easily recharge the controller with your laptop, you cannot play games on that computer using the controller.
PS3 Recharge
The usual recharge process for a PS3 controller is to simply plug it into the PS3 console itself. All PS3s have USB ports, and if you wanted, you could even connect a controller to every port and recharge them all at the same time. You can use one or multiple controllers for gaming even while they recharge on the PS3. Of course, the PS3 must be turned on to recharge the controller; nothing will happen if you plug in the controller while the console is off.
Recharge Indicators
While your controller is charging, whether by a laptop or your PS3, you can look at the LEDs on its top to see if it's still charging or if the recharging is complete. If the LEDs are flashing, then the controller is still charging up. Once the LEDs stop flashing, the controller is fully charged and ready for wireless use. One advantage to charging the controller on your PS3 is that you can observe the battery charge level by pressing and holding the PS button for a few seconds; the battery information will then appear on your TV screen.
Controller Settings
If you want to conserve battery life on your controller, you can adjust a few of the settings so you don't have to recharge as often. One option is to set your controllers to turn themselves off if they're unused for a specified period of time. Navigate horizontally to the "Settings" section of the PS3's XMB menu, and then navigate vertically to the "Power Save Settings" option, where you'll find "Controller Auto-Off." This setting lets you choose a time limit for automatically turning off the controllers. DualShock 3 controllers have the addition of a rumble pack, and although the vibration feature can complement your gaming experience, it does drain the battery more quickly. You can disable this option by navigating to "Settings," then "Accessory Settings," then "Controller Vibration Function."