Maxwell Technologies’ K2 series of ultracapacitor cells provide extended power availability, allowing critical information and functions to remain available during dips, sags, and outages in the main power source. In addition, it can relieve batteries of burst power functions, thereby reducing costs and maximizing space and energy efficiency. The ultracapacitor features a cylindrical design and an electrostatic storage capability that can cycle a million charges and discharges without performance degradation. They are available in quick and easy to implement threaded terminals or in compact, weldable terminals.

The K2 series ultracapacitors are a third generation design that provides 2.7 V operating voltage while improving Maxwell's high performance and high reliability on a high volume manufacturing platform. These cells are ideal for automotive subsystems, medical devices, UPS/backup power, wind turbine pitch control, solar power smoothing, heavy transportation, public transit vehicles and many other applications.

The K2 series works in tandem with batteries for applications that require both a constant power discharge for continual function and a pulse power for peak loads. In these applications, the device relieves batteries of peak power functions resulting in an extension of battery life and a reduction of overall battery size and cost.