CMBlu Energy’s organic flow batteries to be tested in microgrids, cold climates

While flow batteries have been around for a while, they have failed to gain traction and excite investors. However, one of the most promising startups in the field, Germany's CMBlu Energy, recently pulled in more than $100 million in investments and is gradually expanding its market presence.

CMBlu’s technology recently caught the attention of the DoE’s Office of Clean Energy Demonstrations (OCED), which has tasked two prestigious labs, the DoE’s Argonne National Laboratory and Idaho National Laboratory, with validating its credentials.

Over the course of the project, Argonne and Idaho National Laboratory will deploy and evaluate CMBlu Energy’s Organic SolidFlow battery technology with the goal to provide insights for bolstering the resilience of microgrids. The project also seeks to make fast charging of electric vehicles more affordable in rural and underserved communities by reducing charging facility installation and operational costs.

OCED selected the initiative in September to be one of six demonstration projects as part of a long-duration energy storage lab call.

“We’re honored to participate in this project with two preeminent research teams that are advancing clean energy,” said Ben Kaun, president of CMBlu Energy. “The unique capabilities and resources of Argonne and [Idaho National Laboratory] will enable CMBlu to accelerate the commercialization of our Organic SolidFlow battery solution. Our long-duration energy storage is designed to support grid resilience and integration for EV fast charging and microgrid applications, and this demonstration is an excellent opportunity to validate its real-world performance.”

The project will span two regions. In the Midwest, Argonne researchers plan to demonstrate the effectiveness of CMBlu’s technology at the lab’s Smart Energy Plaza. The plaza is a fully renovated and repurposed gas station designed to conduct research on the integration and management of electric vehicle charging, renewables, building systems, and energy storage. Argonne researchers will gather data and analyze how the technology can inform real-world scenarios.

“Demonstration projects, especially those at national labs, efficiently mature our understanding of new technologies in key use cases,” said battery scientist Sue Babinec, program lead for stationary storage at Argonne. “This collaborative project will validate CMBlu’s Organic SolidFlow battery while providing a path for expansion of electric vehicles to underserved communities.”

At the Idaho National Laboratory Battery Test Center in Idaho, researchers will conduct performance tests, including assessing how well the Organic SolidFlow batteries perform at different temperatures. This rigorous testing is crucial to ensure the technology's reliability in diverse environments. The Idaho National Laboratory center serves as the DoE Office of Energy Efficiency and Renewable Energy’s (EERE) primary center for battery life and performance testing.

“This awarded work provides a unique avenue to showcase the strengths of [Idaho National Laboratory] and Argonne to explore flow battery performance at colder-than-room temperatures, relevant to energy storage needs at northern latitudes and winter conditions,” said Kevin Gering, a distinguished staff scientist at Idaho National Laboratory. “We are enthusiastic about applying our collective expertise to understand CMBlu’s Organic SolidFlow battery’s performance so the technology can find those critical niches it can thrive within.”

While other redox flow batteries use metal ions, CMBlu’s Organic SolidFlow batteries use carbon-based molecules for its electrolytes. According to the company, certain carbon-based molecules have the intrinsic ability to be oxidized and reduced or charged and discharged. These molecules are essential elements in the “redox” reactions that power all living cells. 

Energy converter stacks are at the heart of CMBlu’s modular redox flow battery technology. Both reduction and oxidation take place in these stacks although separate from each other. According to CMBlu, the battery output depends on the material and surface area of the electrodes, as well as the kinetics of the redox process. Increasing the stack size yields a higher output.

CMBlu fills two separate storage tanks with a solid polymer and then transfers it to and from the liquid electrolyte, which is pumped into an electrode stack for charging and discharging cycles.

The company's storage technology is intended for use in large-scale, multi-hour stationary projects. The company says it has a “potentially unlimited” cycle life with proper maintenance. It offers up to 90% efficiency, approaching the 95% efficiency of lithium-ion batteries. It can be easily scaled to GWh scale, says CMBlu. The technology is touted as non-flammable.

The company is currently developing multiple pilot projects in the United States and Europe to demonstrate its technology. It has active projects with WEC Energy Group in Wisconsin, Salt River Project in Arizona, and several sites in Europe, including Austrian energy supplier Burgerland Energie's 300 MWh project.

CMBlu was among the winners of the 2018 pv magazine Annual Award for its organic flow battery tech.