Researchers from Lawrence Livermore National Laboratory (LLNL) have developed a 3D-printed electrode design for electrochemical energy storage (EES) devices such as rechargeable batteries and supercapacitors. 

It solves the conflict between high capacity (storing a lot of energy) and high power (releasing it quickly) in storage devices.

The development opted for an optimized, interlocking 3D design to eliminate”dead zones” where ions are typically trapped. This new architecture doubles storage capacity without impacting the charging speed or reliability required for applications such as electric vehicles and grid storage.

“In conventional slab-like designs, a lot of the battery material becomes underutilized because ions cannot reach deep regions efficiently, creating dead zones and concentrated resistive losses near interfaces,” explained Giovanna Bucci, a co-author and staff researcher in the Computational Engineering Division (CED) at LLNL.

Thick electrode problem

Electrochemical energy storage devices rely on a delicate balance between volume and velocity. 

Thick electrodes offer greater storage capacity by housing more active material, but also impede ion movement between the anode and cathode, slowing charging speeds.

To address this challenge, researchers shifted their focus from chemical composition to structural innovation, seeking a design that balances bulk with power.

LLNL researchers have developed a 5.8-millimeter ultra-thick electrode that overcomes the typical performance drop-off seen in bulkier energy storage devices.

In this new work, 3D printing and computational design optimization were combined to create a complex, interlocking electrode structure that maximizes storage space without compromising performance. This architecture maximizes surface area and ensures ions have short, accessible pathways throughout the entire structure.

“The computer can produce geometries that are hard to intuit from experience alone, but are directly aligned with the device’s limiting physics. It helps us understand why certain geometric features are good, and how different geometries are appropriate for different use cases,” said Hanyu Li, CED researcher. 

Advanced materials

Using an optimization framework informed by experimental data, the team fabricated 4-millimeter interdigitated electrodes via multi-material microstereolithography with a specialized resin. 

The two-step process involved printing a porous graphene oxide base to enhance ion fusion, followed by a gold surface layer to boost electronic conductivity. This “interlocking finger” geometry maximizes surface area and eliminates dead zones, providing ions and electrons with numerous entry and exit points for transport.

“This study treats electrode architecture as a performance lever just as important as the material itself,” said Thomas Roy, CED researcher. “The optimized interpenetrating 3D layouts create many accessible pathways for ions, while the integrated conductive network supports electron transport through the structure.”

The optimized electrodes eclipsed both 2D models and previous 3D-printed versions, delivering superior storage capacity, lower resistance, and a robust lifespan exceeding 7,500 cycles. 

Up next, the goal is to scale this framework across diverse applications, such as lithium-ion batteries and electric vehicles. With this scaling, the tech could be brought to high-performance architecture for the next generation of consumer electronics and renewable energy infrastructure.

The findings were published in the journal Materials Horizons.