coconutBattery keeps you informed about your battery health. It displays live information about your battery, such as how frequently it has been charged and what its current maximum capacity is in relation to the original capacity when it left the factory.
You can save the maximum capacity of your battery. You can also see changes in your battery health over the time.
coconutBattery will remain freeware. If you need additional features, there is a Plus version. Go here to purchase.