Check out the new Smart Power Shield for the Arduino at http://smartpowershield.wordpress.com/
The Smart Power Shield provides safe operation and charging of Li-ion Smart Batteries and gives your Arduino project the ability to monitor battery status such as percent charge and minutes of operation remaining.
The Smart Power Shield is a custom Arduino shield and software library that integrates a smart battery charger/controller chip to enable the use of smart batteries. A smart battery takes care of safety critical functions, controls battery charging, and communicates with the Arduino to provide programmatic access to battery status, temperature, voltage, current draw and more. Li-ion Smart Batteries are available in many different voltages and capacities up to 100Wh!
Visit the Smart Power Shield website at http://smartpowershield.wordpress.com/
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