Panasonic's Lithium Ion Battery System For Home Solar Power : Renewable Energy News :

Panasonic Corporation has announced it will commence mass-producing a compact long-life lithium-ion battery system for home solar power applications this month.
 
The Panasonic battery system has a module capacity of 1.35kWh and includes a battery management system designed to control charge and discharge of the battery. The system can store surplus electricity generated by rooftop solar panels for use when needed, further reducing the dependence on grid supplied power.

The lithium-ion battery has a design life time of 5000 cycles, based on an 80% depth of discharge per cycle. This compares very favourably to traditional deep cycle battery technologies such as AGM (Absorbed Glass Mat) and gel; which may only have a serviceable life of 1,500 cycles when discharged to 80%.
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As to the cost of the system, that is unknown at this point, as is a release date for the Australian market. The system will initially be made available to European households via Panasonic's Smart Energy Systems Department; part of the Mobile Energy Business Division of SANYO Component Europe GmbH.
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