Solventless Electrodes in Lithium-Ion Batteries Fabricated through Additive Manufacturing

Abstract

The development of advanced electrode materials is crucial for improving lithium-ion batteries (LIBs), which are increasingly in demand for portable electronics, electric vehicles, and grid storage applications. Traditional electrode fabrication methods often rely on the use of harmful solvents (such as the commonly used NMP), which increases energy consumption, can pose environmental challenges, and at times limit the performance of the electrodes. The use of additive manufacturing (AM) techniques such as direct ink writing (DIW), fused filament fabrication (FFF), and inkjet printing (IJP) has gained significant interest recently due to their potential to fabricate complex, customizable structures without the need for solvents. Yet that potential has not been reached and currently these 3D printing approaches still rely on solvents. A solventless approach can lead to greener manufacturing processes, a decrease in production cost, and the enhancement of electrode performance through precise control over material architecture. Previous studies have explored the potential of additive manufacturing in fabricating electrodes for LIBs, demonstrating the capability to produce three-dimensional structures that maximize the surface area and facilitate efficient ion transport. These materials have shown comparable or superior performance to traditionally fabricated electrodes, with enhanced cycling stability and improved rate capability. These improvements are attributed to the optimized microstructure and better material utilization, which are achievable through precise control over the additive manufacturing process. Other studies have proven the feasibility of solventless fabrication of electrodes by yielding similar results while also saving on costs by cutting down on energy consumption. However, little to no work exists combining the complete elimination of solvents and the AM process. In this work, we employ advanced additive manufacturing techniques to fabricate solventless electrodes for lithium-ion batteries, followed by comprehensive electrical and performance testing to evaluate the cells' efficiency, capacity, and long-term stability. By optimizing the composition and structure of the electrode materials, we aim to enhance these electrochemical. Electrochemical and particle characterization has revealed that solventless electrodes fabricated through optimized additive manufacturing exhibit different microstructures than those of the conventional slurry casted electrodes. Parameters such as printing fidelity, layer thickness, and active material composition can be varied to study their effects on the mechanical, thermodynamic, and electrochemical properties of the electrodes. Using these insights, the next generation of rechargeable batteries can be built with the ability to control design not only making them more efficient, but more applicable. This work aims to investigate a possible method of additive manufacturing that can be used in conjunction with the fabrication of a solventless electrode for lithium-ion batteries. The findings will contribute to the development of greener, more efficient energy storage devices with tailored performance characteristics for a wide range of applications.