Search

Flexible electronics opened a new class of future electronics. The foldable, light and durable nature of flexible electronics allows vast flexibility in applications such as display, energy devices and mobile electronics. Even though conventional electronics fabrication methods are well developed for rigid substrates, direct application or slight modification of conventional processes for flexible electronics fabrication cannot work. The future flexible electronics fabrication requires totally new low-temperature process development optimized for flexible substrate and it should be based on new material too. Here we present a simple approach to developing a flexible electronics fabrication without using conventional vacuum deposition and photolithography. We found that direct metal patterning based on laser-induced local melting of metal nanoparticle ink is a promising low-temperature alternative to vacuum deposition- and photolithography-based conventional metal patterning processes. The digital nature of the proposed direct metal patterning process removes the need for expensive photomask and allows easy design modification and short turnaround time. This new process can be extremely useful for current small-volume, large-variety manufacturing paradigms. Besides, simple, scalable, fast and low-temperature processes can lead to cost-effective fabrication methods on a large-area polymer substrate. The developed process was successfully applied to demonstrate high-quality Ag patterning (2.1 µΩ·cm) and high-performance flexible organic field effect transistor arrays.

A microscopic finite element model validated by the quasi-static mechanical test on lithium ion battery cell is presented in this study. The investigated condition involves three-point bending and cell discharge test, which include the mechanical response and thermal response of lithium ion battery cell. The cell is investigated through computational simulation. Results show great correlation between the experiment and finite element simulation. A microscopic model requires a greater effort during simulation. Investigating the fracture on steel casing and cell core is possible by considering the fracture mechanism in steel shell and jelly roll. The classic von-Mises criterion is applied to predict the failure of carbon steel shell, and the maximum von-Mises strain criterion is used to investigate the jelly roll region. On the basis of the verified battery cell model, battery package with microscopic model, including cell core (cathode, anode, and separator) is constructed to analyze the mechanical response of battery pack. The von-Mises criterion is used to predict the fracture point location of the battery pack with various packing modes and packing densities. [ABSTRACT FROM AUTHOR]