Your New Notebook
Be sure to fully charge your portable when you plug it in for the first time, and then run Software Update to ensure you have the latest software. Apple periodically releases updates that may improve battery performance.
For proper maintenance of a lithium-based battery, it’s important to keep the electrons in it moving occasionally. Apple does not recommend leaving your portable plugged in all the time. An ideal use would be a commuter who uses her MacBook Pro on the train, then plugs it in at the office to charge. This keeps the battery juices flowing. If on the other hand, you use a desktop computer at work, and save a notebook for infrequent travel, Apple recommends charging and discharging its battery at least once per month. Need a reminder? Add an event to your desktop’s iCal.
With a little bit of care, you can maximize the battery life (i.e. the time your battery will run before it must be recharged) and lifespan of your notebook's battery. Most importantly, use your Apple notebook in its comfort zone for temperature (See “Notebook Temperate Zone”). Don’t leave it locked in a hot trunk during the summer.