Optimising formulations for 3D printed solid-state batteries
Batteries store and discharge energy through the movement of positive ions and negative electrons. They also contain an electrolyte that facilitates the movement of positive ions to create an electrical current.
Conventional batteries contain a liquid electrolyte, which is often flammable and hazardous. Solid-state batteries contain a solid electrolyte, which is significantly safer, however, they are often expensive and have design limitations.
To develop customisable, conformable, and safe batteries for use in novel applications, we collaborated with Photocentric to test whether additive manufacturing (3D printing) techniques could be applied to solid-state battery technology. To enable this, we needed to develop a functional 3D printable ink formulation that could carry an electrical charge.
“With CPI’s help, we now have a solid proof-of-concept that we’ve been able to move forward in the development process to higher TRL levels. CPI aided in delivering results and knowledge with a reduced capital investment, allowing us to to achieve our goal in a shorter time span.”
How CPI helped
- Applied expertise and capability in ink formulation and extrusion
- Explored a selection of materials that could be UV curable, and therefore 3D printable, using Photo-DSC
- Applied high throughput automation capabilities to explore a wide range of formulations
- Tested battery functionality using Electrical Impedance Spectroscopy (EIS) to efficiently measure ionic conductivity
- Overcame common UV curing challenges when using light blocking materials to develop a UV curable printable resin
- Developed and optimised a polymer electrolyte formulation into a printable resin
- Printed the cathode materials using a functional binder via a Fused Deposition Modelling process, removing the need for energy-intensive sintering processes
The project delivered a big breakthrough by proving that it is feasible to 3D print a solid-state battery that is less hazardous and more sustainable than conventional lithium-ion batteries. There is now the possibility of moving beyond the traditional ‘flat pack’ battery model, with the freedom to develop new shapes and forms of EV (electric vehicle) batteries.
For battery and electric vehicle manufacturers, the ability to 3D print batteries means boosted manufacturing efficiency alongside real freedom of form. This means that rather than a vehicle’s design being constrained by the size and shape of a standard battery, a battery can be made to fit into a vehicle’s design. This could enable bespoke, and high-performance EV battery applications where space is at a premium, for example in Formula E, wearables, and drones.
Following our collaboration, Photocentric has received continued funding and has been able to continue to develop the project seamlessly, delivering further promising results. As development progresses, it is expected that this method of 3D printing batteries could also result in reduced costs for manufacturers.
The UV curable formulations developed in the project could also be applied to the development of a wider range of inks for additive manufacturing and roll-to-roll printing, for example electrically conductive inks for producing IoT devices.