Maxwell Grid Cell Pack

Scalable Building Block Energy Storage Module for Microgrids and Behind the Meter Demand and Power Quality Management

Project developers and systems integrators for microgrids, remote grids, and commercial/industrial facilities require a high degree of flexibility in the design of their energy storage systems. Modern energy storage systems are called on to provide advanced technical functionality when islanded as well as being "right sized” to ensure financial justification. Critical loads today require power on demand, fast response times and high equivalent c-rates capable of mitigating voltage and frequency deviances common to microgrid deployments in island mode and C&I behind-the-meter power quality anomalies.

Maxwell’s Grid Cell Pack is a rackable, stackable module with advanced diagnostics and communications enabling reliable performance in high power, fast response applications scalable from KW's to MW's. An open architecture simplifies cooling to reduce system cost and complexity. The cell pack dispatches power in milliseconds and can be deployed to stabilize frequency, provide voltage support, smooth renewable power output, and provide bridging power as a stand-alone energy storage resource or when combined with batteries.

Advanced Diagnostics and Communication

The Grid Cell Pack features Maxwell’s new cell management system (CMS) enabling advanced system-level prognostic/diagnostic capabilities designed to ensure system reliability and long system-level life, with digital communication functionality for integration with system controller.

In addition to near real time cell balancing, the on-board feature to read and store cell voltage and temperature ensure long life and system uptime with advanced monitoring. The module also features Maxwell Technologies’ High Voltage Interlock Loop (M-HVIL™) to enable the advanced functionality of internal system fail-over, providing an additional level of safety to your field assets. The cell packs can communicate directly via the internal CAN bus, or integrated with Maxwell’s communications gateway to communicate via Modbus or Profinet to your higher-level controller.

Building Blocks


The Maxwell Grid Cell Pack is based on utility requirement-driven design expertise, with a critical eye on power system integration at the microgrid level and also for behind-the-meter C&I applications. Maxwell works directly with global utility equipment OEMs and your preferred suppliers to deliver optimized solutions based on specific technical project needs that are higher performance and lower cost than stand-alone battery energy storage.

Project Modeling

Maxwell offers industry leading lifetime prediction capability with our advanced ultracapacitor cell lifetime estimation tools based on over 3 million hours of product testing. With this foundation, Maxwell’s grid solutions team works hand-in-hand with stakeholders and uses state-of-the-art tools to model system dynamics when integrated in the power grid with traditional and renewable generation resources along with grid control systems. This provides the technical justification, financial justification and deep analysis required by the utility, project developers, ratepayers and appropriate regulatory and governmental bodies.


Maxwell’s Grid Cell Pack can be integrated and deployed in microgrids as well as behind-the-meter facilities. Applications include:

Solar and Wind Power Firming 
Mitigate msec-sec timeframe power fluctuations to ensure local power quality, especially on long feeders or with a high penetration of renewable energy. Enable interconnection of more renewable projects which would otherwise require costly infrastructure investment.

Maxwell ultracapacitors are deployed as a stand-alone asset or integrated with batteries to provide near real time frequency, voltage and power firming and smoothing in island mode. These devices meet the most demanding transient and pulsed power loads and provide the highest level of availability and reliability in support of utility microgrids, commercial and industrial microgrids, campuses and industrial parks, and critical assets including defense and military microgrids.

Voltage Sag Mitigation and UPS   
In utility grids and microgrids, Maxwell ultracapacitors provide voltage, frequency and power stabilization in near real time. Fast responding, transient response capability mitigates deep and/or recurring power sags from cycles to minutes. In manufacturing and C&I facilities, ensure delivered power meets ANSI, CBEMA and SEMI standards for continuous operations and to mitigate risk of financial loss. Systems can be sited on utility side or customer side-of-meter and occupy a significantly smaller footprint providing faster response than alternative battery and generator solutions.

Primary Frequency Response 
Renewables do not provide the necessary inertia and short circuit power to the power system. Maxwell ultracapacitors provide fast frequency response (FFR) as a stand-alone system or integrated with batteries. Fast, reliable cycles timeframe response for synthetic inertia can also be provided when integrating with SVC, STATCOM or as a replacement to SYNCON. Enable interconnection of assets such as PV and wind, stabilize voltage and frequency while replacing the system inertia deficit due to retired fossil and nuclear generation plants. Fast response to mitigate, in near real time, a decrease in generation, generation-load imbalance and unpredictable variations in demand.

Generator Bridging, Ramping, and Regulation
Maxwell ultracapacitors provide controlled ramp rates from cycles-to-seconds-to-minutes until generator ramp is complete. Reduce the need for idling resources and reduce fuel consumption. Fast responding energy storage to respond to an increase or decrease in generation (or load), to respond to markets or random, unpredictable variations in demand.

Rail to Utility – Wayside Rail Energy Recovery
Provide assisted propulsion, bridge power, and grid/voltage stabilization.

Hybrid Storage – Asset Optimization and Stacked Services
New levels of stacked functionality are now achieved by integrating traditional Li-ion and other battery chemistries with ultracapacitors. Capacity, peak load management, energy arbitrage, near real time voltage and frequency stabilization and regulation, FFR (fast frequency response), synthetic inertia, bridging and ramping can be combined in one system to maximize asset use, increase benefit-to-cost ratio and decrease payback period. Contact us and we will show you how.

See our utility grid page for more information.

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Established in 1965, Maxwell Technologies has been a trusted supplier of high-tech energy solutions for customers worldwide. Over the past 20 years, system designers across industries have leveraged the power and speed of Maxwell’s ultracapacitor cell technology. Maxwell’s quality and proven field reliability is evidenced in the over 8 million devices provided to grid applications and 65 million ultracapacitors deployed in systems for automotive, heavy transportation, renewable energy and industrial applications.

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*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 requirements.