Maxwell has produced more than 20 million ultracapacitor cells since setting up initial high-volume production, according to David Schramm, the company’s president and CEO. Ultracapacitor sales have grown by more than 500% since 2007.

The new electrode plant will be housed in a 123,000 square-foot facility the company has leased in Peoria, Arizona, near Phoenix. To date, all of the proprietary electrode material used in Maxwell ultracapacitor products has been produced at the company’s San Diego facility.

In 2011, Maxwell and an assembly partner built and shipped more than 2 million large cell ultracapacitors, and a new large cell assembly line scheduled to come on line later this year will increase current capacity by 50%. Large cells are used mainly in hybrid and electric public transit vehicles for braking energy recuperation and torque assist. The company also supplies large cells to Continental AG, a global Tier 1 auto parts supplier, for a stop-start idle elimination system introduced by PSA Peugeot Citroën in Europe for the 2011 model year.

Working with another contract assembly partner, Maxwell brought on line a high-volume assembly line in mid-2010 for its redesigned, 350-farad “D-cell” ultracapacitor products, which are used mainly in wind turbine blade pitch mechanisms.

A third contract manufacturer assembles Maxwell’s HC family of small cell products, which range from one to 150 farads, and are used mainly in industrial electronics applications.

The company also has expanded production capacity for its postage stamp-size, 10-farad PC-10 ultracapacitor cell to satisfy rapidly increasing demand for a backup power application in solid state drives used in enterprise computing systems. Previously, Maxwell also has delivered several million PC 10s to power wireless transmitters in automated electric utility meters and other devices.

Maxwell offers ultracapacitor cells ranging in capacitance from one to 3,000 farads and multi-cell modules ranging from 16 to 125 volts.