Recent Progress on Printed Flexible Batteries: Mechanical Challenges, Printing Technologies, and Future Prospects

Traditional printing methods offer the advantage of well‐matured technology, high accuracy of depositing inks over flexible substrates at high web speeds, and low cost of fabrication. The components of a battery—the current collectors, active layers, and separator—can all be deposited using conventional printing techniques by designing suitable inks. A combination of low thickness of printed electrodes, flexible packaging, battery architecture, and material properties makes printed batteries flexible. In this paper, we will discuss material challenges and mechanical limits of flexible printed batteries. We will review several printing techniques and present examples of batteries printed using these methods. In addition, we will briefly discuss other novel non‐printed compliant batteries that have unique mechanical form. Printed flexible batteries: Compliant power sources are necessary for powering the next generation of flexible and wearable electronic devices. In this Review, the material challenges and mechanical limits of flexible printed batteries are discussed. The authors review several printing techniques, and present examples of batteries printed using these methods, in addition to introducing other novel non‐printed compliant batteries that have unique mechanical form.