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Abstract Lithium‐ion battery electrodes are manufactured using a new additive manufacturing process based on dry powders. By using dry powder‐based processing, the solvent and its associated drying processes in conventional battery process can be removed, allowing for large‐scale Li‐ion battery production to be more economically viable in markets such as automotive energy storage systems. Uniform mixing distribution of the additive materials throughout the active material is the driving factor for manufacturing dry powder‐based Li‐ion batteries. Therefore, this article focuses on developing a physical model based on interfacial energies to understand the mixing characteristics of the dry mixed particulate materials. The mixing studies show that functional electrodes can be manufactured using dry processing with binder and conductive additive materials as low as 1 wt% due to the uniformly distributed particles. Electrochemical performance of the dry manufactured electrodes with reduced conductive and binder additive is promising as the cells retained 77% capacity after 100 cycles. While not representative of the best possible electrochemical performance of Li‐ion batteries, the achieved electrochemical performance of the reduced conductive and binder additive electrodes with LiCoO2as the active material confirms the well distributed nature of the additive particles throughout the electrode matrix.
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Scalable Dry Printing Manufacturing to Enable Long‐Life and High Energy Lithium‐Ion Batteries
Abstract Slurry casting method dominates the electrode manufacture of lithium‐ion batteries. The entire procedure is similar to the newspaper printing that includes premixing of cast materials into solvents homogeneously, and continuously transferring and drying the slurry mixture onto the current collector. As a market approaching US $80 billion by 2024, the optimization of manufacture process is crucial and attractive. However, the organic solvent remains irreplaceable in the wet method for making slurries, even though it is capital‐intensive and toxic. Here, an advanced powder printing technique is demonstrated that is completely solvent‐free and dry. Through removing the solvent and related procedures, this method is anticipated to statistically save 20% of the cost at a remarkably shortened production cycle (from hours to minutes). The dry printed electrodes outperform commercial slurry cast ones in 650 cycles (80% capacity retention in 500 cycles), and thick electrodes are successfully fabricated to increase the energy density. Furthermore, microscopy techniques are utilized to characterize the difference of electrode microstructure between dry and wet methods, and distinguish dry printing's advantages on controlling the microstructure. In summary, this study proves a practical fabrication method for lithium‐ion electrodes with lowered cost and favorable performance, and allows more advanced electrode designs potentially.
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- Award ID(s):
- 1640647
- PAR ID:
- 10038803
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 2
- Issue:
- 10
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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