K2 2.7V Series

Maxwell Technologies’ K2 2.7V series of ultracapacitors can relieve batteries from peak power functions, provide extended power availability, and help customers to reduce costs and maximize both space and energy efficiency in the overall system.

Our K2 ultracapacitors provide protection for critical operation when dips, sags and outages occur and ensure that important functions remain available. The K2 2.7V series is also an ideal source of backup power. When power is needed in spikes, the K2 2.7V series can reduce peak power demands on the grid, batteries or generators. And, like all Maxwell ultracapacitors, this series is capable of accepting charges at the identical rate of discharge.

The K2 ultracapacitors are ideal for a variety of applications, including:

Our ultracapacitors feature 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.

Works with Batteries
The K2 2.7V 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 ultracapacitors relieve batteries of peak power functions, resulting in extended battery life and a reduction in overall battery size and cost.


  • Up to 1,000,000 duty cycles or 10-year DC life
  • High power density
  • 650F and 3000F capacitance range
  • Threaded terminals or laser-weldable posts
*Results may vary. Additional terms and conditions, including the limited warranty, apply at the time of purchase. See the warranty details and enclosed information for applicable operating and use requirement.