PNNL

They’ve been powering smartphones and electric vehicles for years—but now, from fortifying the electric grid to fueling freight transportation and critical defense systems, lithium-based batteries are increasingly vital to American industry and security. 

There’s just one catch: The batteries rely on “critical materials,” such as lithium and cobalt, that have volatile prices and carry a high risk of supply chain disruption.

Enter the Low-cost Earth-abundant Na-ion Storage (LENS) consortium. Funded by the Department of Energy’s (DOE’s) Vehicle Technologies Office and launched in November 2024, the consortium includes six DOE national laboratories, including Pacific Northwest National Laboratory (PNNL) and eight universities. LENS is a major research and development effort to create superior, no-compromise batteries that replace lithium with inexpensive, domestically abundant sodium and use few—if any—critical materials.

Establishing sodium superiority

As one of the world’s leading producers of sodium-rich compounds, the United States is exceptionally well-equipped to supply the raw materials for sodium-ion batteries. A battery supply chain based on domestic sodium rather than imported critical materials would be more resilient and give the United States a competitive edge in the global energy storage market. 

But there’s a reason lithium-ion batteries continue to dominate the market: Present-day sodium-ion batteries have much lower energy density—that is, energy stored per unit weight or volume—than their lithium-based competition. Holding everything else equal, a sodium-based battery simply wouldn’t deliver as much energy.

The LENS consortium aims to change that by developing sodium-ion batteries that match—and eventually, surpass—the energy density of lithium iron phosphate (LFP, LiFePO₄) batteries. This would eliminate the need for not only lithium but also the graphite, cobalt, and potentially nickel commonly used in the anodes and cathodes of lithium-based batteries.

To do that, the consortium, led by Argonne National Laboratory, is applying world-class expertise to tackle sodium-ion battery technology across its anode, cathode, electrolyte, interfaces, inactive materials, and more.

LENS at PNNL

Each member of LENS was carefully chosen to tackle a specific scientific challenge according to their unique capabilities and expertise. For PNNL, that’s the electrolyte: the material that helps transfer ions between the battery’s electrodes and maintain the cycling performance of the whole system.

“At PNNL, we’re developing a new class of advanced electrolytes and additives to enable long cycle life and safe operation for sodium-ion batteries,” said Phung Le, an electrochemist and PNNL’s principal investigator in the LENS consortium. 

“The first results are very promising,” Le said. “The electrolyte team has developed a localized high-concentration electrolyte, and we’ve shown that the electrolyte is compatible with high-voltage commercial pouch cells.”

Le also explained that the electrolyte appears to completely eliminate gas evolution during battery cycling—a phenomenon that can cause sodium-ion batteries to swell, affecting performance and safety.

The other members of LENS are hard at work making other components of the prototype battery. Le mentioned, for instance, a new cathode material that uses cheap, abundant manganese and iron instead of nickel.

PNNL will eventually send its electrolyte to Argonne, which will combine PNNL’s electrolyte with the other members’ novel components and materials, creating a complete 2-amp-hour battery prototype for testing. 

But that won’t be the end of the sodium-ion battery research for LENS or PNNL.

“We’ll be combining materials that have properties, mechanisms, and interactions that we don’t fully understand,” Le said. “Once the prototype battery is created, we’ll need to carefully study how it performs relative to our expectations. We’ll also continue to explore the interface phenomena at a small scale in our coin cell batteries.”

PNNL’s LENS research is conducted in the Grid Storage Launchpad, the Laboratory’s one-stop shop for energy storage research that opened its doors in August 2024.

What’s in store for LENS

Over the course of the five-year consortium, LENS researchers will look to hit specific milestones for the efficacy, composition, and cost of their prototype sodium-ion cells. The researchers hope that by the end of the project, LENS will have helped to significantly advance the creation of a resilient domestic supply chain for energy storage and thus support U.S. competitiveness in battery development.

“If successful, the LENS consortium will advance fundamental science, strengthen our domestic energy storage supply chain, and greatly reduce costs for grid and vehicle energy storage,” Le said. 

The LENS consortium, which is funded by the DOE’s Vehicle Technologies Office, includes six national laboratories: Argonne National Laboratory, PNNL, Brookhaven National Laboratory, Lawrence Berkeley National Laboratory, Sandia National Laboratories, and SLAC National Accelerator Laboratory. The universities participating in the consortium are Florida State University, University of California, San Diego, University of Houston, University of Illinois Chicago, University of Maryland, University of Rhode Island, University of Wisconsin–Madison, and Virginia Tech.