New 3D-printing method may improve smartphone batteries

Scientists, including one of Indian origin, have developed a new method to 3D print battery parts that can vastly improve the capacity and life of smartphone batteries.

3D printing, also known as additive manufacturing, can be used to manufacture porous electrodes for lithium-ion batteries. However, due to the nature of the manufacturing process, the design of these 3D printed electrodes is limited to just a few possible architectures.

Researchers from Carnegie Mellon University and Missouri University of Science and Technology in the US developed a method of 3D printing battery electrodes that creates a 3D microlattice structure with controlled porosity.

"In the case of lithium-ion batteries, the electrodes with porous architectures can lead to higher charge capacities," said Rahul Panat, an associate professor at Carnegie Mellon.

"This is because such architectures allow the lithium to penetrate through the electrode volume leading to very high electrode utilisation, and thereby higher energy storage capacity," Panat said.

3D printing this microlattice structure improves the capacity and charge-discharge rates for lithium-ion batteries, according to the research published in the journal Additive Manufacturing.

Until now, the internal geometry that produced the best porous electrodes through additive manufacturing was what's known as an interdigitated geometry - metal prongs interlocked like the fingers of two clasped hands, with the lithium shuttling between the two sides.

Lithium-ion battery capacity can be vastly improved if, on the microscale, their electrodes have pores and channels.

An interdigitated geometry, though it does allow lithium to transport through the battery efficiently during charging and discharging, is not optimal.

"In normal batteries, 30-50 per cent of the total electrode volume is unutilised. Our method overcomes this issue by using 3D printing where we create a microlattice electrode architecture that allows the efficient transport of lithium through the entire electrode, which also increases the battery charging rates," Panat said.

The research represents a major advance in printing complex geometries for 3D battery architectures, as well as an important step toward geometrically optimising 3D configurations for electrochemical energy storage.

The researchers estimate that this technology will be ready to translate to industrial applications in about 2-3 years.