PolyJoule, a Massachusetts-based developer of conductive polymer battery technologies, has introduced a third-generation battery chemistry designed for stationary energy storage applications requiring improved fire safety, long cycle life, and simplified thermal management.
Founded as a tech spin-out from the Massachusetts Institute of Technology (MIT), the company’s latest large-format prismatic cell incorporates a new conductive polymer cathode and liquid salt electrolyte designed to support battery energy storage applications in environments where conventional lithium-ion battery technologies may present operational or thermal management challenges.
According to PolyJoule, the third-generation chemistry was developed to address several issues commonly associated with lithium-ion battery systems, including fire safety concerns, system complexity, and supply chain dependence on foreign-sourced materials.
PolyJoule develops conductive polymer battery technologies designed for long-duration stationary energy storage and improved operational safety. (Photo courtesy of PolyJoule)
PolyJoule states that the chemistry is designed to self-extinguish under extreme thermal conditions and does not require active thermal management, potentially simplifying system design and operation across commercial, industrial, and residential energy storage environments.
“PolyJoule has always been at the forefront of energy storage safety,” said Eli Paster, PolyJoule’s co-founder and CEO. “We were the first company in the world to prove through UL 9540A testing that our conductive polymer cells do not go into thermal runaway. We approached this next-gen chemistry with a very simple thesis: Batteries shouldn’t start fires. Batteries shouldn’t spread fires. Batteries shouldn’t catch on fire.”
Unlike conventional battery chemistries that rely on metallic charge-storing materials, conductive polymers store charge along an organic backbone rather than within a crystalline lattice structure. According to the company, this approach can support longer cycle life while avoiding dendrite formation associated with some battery technologies.
“The advantage of PolyJoule’s batteries is that they have neither,” said Timothy Swager, the John D. MacArthur Professor of Chemistry at the Massachusetts Institute of Technology and a co-founder of PolyJoule who serves as a technical advisor to the company. “PolyJoule has created a product that can safely be put inside homes and businesses, using non-flammable conducting polymers and a liquid salt electrolyte that has a vapor pressure a billion times lower than that of the electrolytes used in Li-ion batteries.”
PolyJoule stated that the third-generation chemistry delivers a 10-fold improvement in energy density compared to the company’s first-generation platform while maintaining cycle life exceeding 10,000 cycles.
The company also noted that the chemistry is intended to support domestic supply chain sourcing while simplifying deployment for stationary energy storage systems used in grid resilience, renewable energy integration, backup power, and distributed energy infrastructure applications. PolyJoule said it plans to begin accepting applications from qualified solar, battery, and generator installers in select markets later this year.
About PolyJoule
PolyJoule is a Boston-area energy storage technology company focused on conductive polymer battery systems designed for stationary energy storage applications. Spun out from the Massachusetts Institute of Technology, the company develops non-metallic, rare-earth-free battery technologies intended to support long-duration energy storage, grid resilience, renewable energy integration, and electrification infrastructure.
PolyJoule’s battery systems are designed and manufactured in the United States and focus on applications requiring long cycle life, operational safety, simplified thermal management, and domestic supply chain sourcing. For more information, please click here.
Source/Photo Credit: PolyJoule
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