In the articles linked below from Microsoft, there are some tips that you can use to recharge a battery and extend laptop battery life, and how to take advantage of Windows settings to manage power more efficiently.

Managing Battery Life and Power Consumption Overview

Conserving battery power

Basic steps to maintaining your battery, extending it's charge time and life are listed below and explained in thier entierty in the linked article:

Treat your battery right

• Charge your battery correctly
• Keep your battery cool
• If your battery is replacable, carry a spare
• Store it properly

Optimize your power settings

See this article for information on how to adjust your power settings - Adjusting Power Options in Windows

Take advantage of low-power states

• Sleep (Standby)
• Hibernation
• Hybrid Sleep

Adjust screen brightness

Turn off wireless

Additional power-saving tips

• Turn off scheduled tasks
• Keep the use of tools in the notification bar to a minimum
• Limit power-intensive activities

By adjusting your mobile PC settings to conserve battery power and by implementing these tips, you can relieve the inconvenience of running out of battery power.