British researchers are developing a new method for producing lithium for batteries using engineered proteins that assemble into membranes with pores as small as 1 angstrom, potentially allowing the separation of lithium from chemically similar sodium.
The approach uses S-layer proteins that naturally form highly ordered structures on the surface of microorganisms. Researchers want to modify these proteins to create membranes with uniformly sized pores that can selectively separate lithium and sodium ions.
Scientists at the University of Birmingham and Aston University are aiming for pore sizes in the range of 1 to 50 angstroms, with one angstrom being one ten-billionth of a meter. The aim is to produce large-area membranes that can carry out highly selective separations under practical operating conditions.
The three-year project received £6.2 million from the UK’s Advanced Research and Invention Agency (ARIA). Researchers will design and test thousands of protein variants before scaling the most promising candidates for membrane manufacturing and testing.
Proteins form programmable pores
The proposed membranes will use S-layer proteins, which naturally form ordered, two-dimensional structures on the surface of many microorganisms.
These proteins can assemble into repeating patterns without the need to position each component individually. Researchers plan to modify their structures to create pores with controlled dimensions and chemical properties.
Thousands of protein variants are being designed and studied to identify candidates that can separate lithium and sodium ions. The most promising versions are then manufactured on a larger scale and integrated into membrane systems.
“Biology can engineer ordered materials with a precision that is extremely difficult to achieve with existing manufacturing methods. We want to use this to create membranes with uniform, programmable pores,” said project leader Dr. Dominik Kubicki from the University of Birmingham.
Fold9 will lead the computational design of the proteins, while Adaptyv Bio will perform high-throughput screening to test large numbers of variants. UK-based Evove will contribute expertise in membrane manufacturing, scaling and testing.
In addition, researchers will use cryogenic electron microscopy (cryo-EM) and neutron reflectometry to study membrane structures at the nanoscale. These techniques will help determine how changes in pore geometry affect ion selectivity, stability and transport.
Scaling membranes beyond laboratories
A key challenge will be to convert precisely engineered protein structures into continuous membranes that function under practical industrial conditions.
The team plans to combine protein production, membrane fabrication and testing to assess whether the materials retain their selective properties when manufactured at larger scales.
“A key challenge will be to translate control at the molecular level into membranes that can be manufactured and operated at meaningful scales,” said Professor Owen Thomas from the University of Birmingham.
The project is part of ARIA’s Universal Fabricators program, which explores the use of engineered proteins as building blocks for producing materials with controlled structures.
Although lithium extraction is the initial goal, researchers believe the approach could ultimately support water treatment, critical mineral recovery, and chemical and pharmaceutical production.
The technology is still in the development stage. The team has not yet reported a functioning membrane on an industrial scale, nor lithium recovery rates or measured energy savings.
The three-year program will test whether engineered proteins can deliver the selectivity, durability and scalability required for practical separation systems.
