Accubattery - Monitor's battery capacity through the use of science
BatteryCare - BatteryCare - Application and good practice guide for maintaining and optimizing the battery of the modern laptop
Battery Health - FIPLAB is an award winning application development studio in London that specialises in creating intrinsically viral, high quality iPhone, iPad, Mac and Windows 8 applications.
coconutBattery - With coconutBattery you are always aware of your current battery health. It shows you live information about the battery in your Mac and iOS devices (iPhone, iPad)
BatteryMon - BatteryMon is a battery monitoring software solution.
iStat Menus - "An advanced Mac system monitor for your menubar."