PolyPlus Achieves Major U.S. Battery Manufacturing Milestone: Product Line Established for Protected Lithium Electrodes and Lithium Seawater Batteries that Deliver Record Setting Energy Density of 2000 Wh/kg.

BERKELEY, Calif., July 14, 2022 /PRNewswire/ — PolyPlus Battery Company (“PolyPlus”), a privately-held company focused on the development of next generation batteries, is pleased to announce that it has installed a pilot manufacturing line for producing advanced Lithium Seawater Batteries (Li/SWBs) for subsea and deep ocean applications. These batteries have unprecedented energy density of 2000 Wh/kg and >1500 Wh/l. The manufacturing line is now fully operational at PolyPlus’ facility in Berkeley, California allowing interested government, academic and industry customers to obtain fully functional batteries in support of applied research and development projects.


Lithium seawater batteries provide key advantages over other primary batteries (such as lithium thionyl chloride) including a 10X increase in energy density along with inherent safety. This revolutionary technology is based on water-stable Protected Lithium Electrodes (PLEs) invented by PolyPlus that enable the construction of pressure tolerant batteries, having zero self-discharge, and exceptional energy density. Depending on size and form factor, the batteries can reach energy densities of 2000 Wh/kg and >1500 Wh/l, which is an order of magnitude greater than competing technologies, including Li-ion. PolyPlus’ Li/SWB represents a game changing technology for long endurance applications, including deep ocean sensors and subsea nodes. Lithium/seawater batteries built by PolyPlus do not require a pressure housing (pressure housings significantly degrade the energy density of conventional batteries) and accordingly Li/SWBs deliver extremely high energy density in practice. They also are close to neutral buoyancy and are exceptionally safe for use and storage on maritime vessels, vehicles and aircraft.

The PolyPlus lithium seawater battery can be arranged in a number of geometric formats, including a tubular stacking of individual cells with a total battery energy that is readily customized (e.g., from 100 Wh to > 10 kWh). Recent Navy-sponsored open water tests of PolyPlus’ batteries with a rated capacity of 200Ah demonstrated and confirmed that the PLE and batteries are capable of deployment and operation without a pressure housing in a relevant operating environment. PolyPlus is also working on high-rate lithium seawater batteries suitable for powering autonomous vessels and in particular for extending the mission duration of unmanned underwater vehicles (UUVs).

Completion of the pilot production line allows government and industry partners to purchase fully operational batteries, validate the performance of the batteries, and enable emerging maritime platforms. Working with PolyPlus’ technical team, customers can modify the form, fit and function of the batteries to meet a broad set of energy needs.

“PolyPlus Battery Company is grateful for the long-term support that we have received from the Office of Naval Research on the development of lithium seawater batteries and more recently from the Defense Production Act Title III program for the manufacture of this game changing battery for marine applications” said Steve Visco, PolyPlus CEO. Visco underscored the important role that the Department of Energy (DOE) has played in early recognition and support of our PLE and PLE based battery technologies. “We are exceptionally thankful to the DOE Advanced Manufacturing Office and ARPA-E (Advanced Research Projects Agency-Energy) for their substantial support of our groundbreaking PLE battery technologies and manufacturing developments,” Visco also said.


Learn more about the Lithium Seawater Battery >


About PolyPlus

PolyPlus Battery Company is headquartered in Berkeley, CA, and is a world leader in the development of next-generation battery technology. The Company invented and patented the protected lithium electrode (PLE) which is a core technology of our commercially ready lithium seawater battery and enabling of other high area capacity lithium battery chemistries, such as lithium-air. PolyPlus is also at the cutting edge of rechargeable Li metal battery technology. Our solid-state glass-protected lithium metal electrode is a disruptive technology that can address the huge demand for a superior energy dense solid-state secondary battery for electric vehicles and most applications that are currently powered by Li-ion. PolyPlus has a world-class team of scientists and engineers and a rich pool of intellectual property totaling more than 230 granted and pending patents. The PLE was recognized by TIME magazine as one of the 50 Best Inventions of 2011, and by the Edison Committee with a Gold Edison Award in 2012. For more information, please visit www.polyplus.com.


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SOURCE PolyPlus Battery Company