BatteryCare

Does your laptop battery die while you're working, or does it no longer seem to hold a full charge? BatteryCare is a free utility for Windows laptops that helps you look after the battery and get the most out of each charge.  It monitors the battery's discharge cycles, shows detailed information about its capacity and wear, and reminds you when the battery should be calibrated. It can also switch power plans automatically and turn off Windows features that drain power while the laptop runs on battery. BatteryCare is developed by Filipe Lourenço, is available in 13 languages and also comes as a portable version. 

Features:

• Discharge cycle monitoring - BatteryCare records every complete discharge cycle and notifies you when a calibration is recommended, which keeps the charge level reported by the battery accurate. It shows detailed battery information such as the designed and current capacity, the wear level and the power consumption, and it calculates a statistical remaining time on laptops that do not report it.  
• Automatic power plans - BatteryCare switches to the power plan you choose whenever the laptop is plugged in or running on battery. It also monitors the CPU and hard drive temperatures in Celsius or Fahrenheit, with user-defined temperature alarms. 
• Notification system - a tray icon and a compact Quick Info pop-up show the temperatures, charge status, remaining time and active power plan, and notifications tell you when an action is needed. In battery mode the program can disable the Aero theme and Sidebar gadgets and pause demanding Windows services that shorten battery life.
• System performance - the software uses only about 0.1 percent of processor and memory resources, so it can run in the background all the time. It can search for updates at startup and update itself, so you don't need to download new versions manually. 

BatteryCare helps preserve laptop battery life by tracking discharge cycles and reminding you when to calibrate the battery.