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Aluminum foil is the predominant cathodic current collector in lithium-based batteries due to the high electronic conductivity, stable chemical/electrochemical properties, low density, and low cost. However, with the development of next-generation lithium batteries, Al current collectors face new challenges, such as the requirement of increased chemical stability at high voltage, long-cycle-life batteries with different electrolyte systems, as well as improved electronic conductivity and adhesion for new electrode materials. In this study, we demonstrate a novel graphene-like carbon (GLC) coating on the Al foil in lithium-based batteries. Various physical and electrochemical characterizations are conducted to reveal the electronic conductivity and electrochemical stability of the GLC-Al foil in both carbonate- and ether-based electrolytes. Full-cell tests, including Li–S batteries and high-voltage Li-ion batteries, are performed to demonstrate the significantly improved cycling and rate performance of batteries with the use of the GLC-Al foil as current collectors. The cell using the GLC-Al foil can greatly reduce the potential polarization in Li–S batteries and can obtain a reversible capacity of 750 mAh g–1over 100 cycles at 0.5C. Even with high-sulfur-loading cathodes, the Li–S battery at 1C still maintains over 500 mAh g–1after 100 cycles. In high-voltage Li-ion batteries, the GLC-Al foil significantly improves the high-rate performance, showing an increased retained capacity by over 100 mAh g–1after 450 cycles at 1C compared to the bare foil. It is believed that the developed GLC-Al foil brings new opportunities to enhance the battery life of lithium-based batteries.

In this article, we describe a writable particle-free ink for fast fabrication of highly conductive stretchable circuits. The composite ink mainly consists of soluble silver salt and adhesive rubber. Low toxic ketone was employed as the main solvent. Attributed to ultrahigh solubility of silver salt in short-chain ketone and salt-assisted dissolution of rubber, the ink can be prepared into particle-free transparent solution. As-prepared ink has a good chemical stability and can be directly filled into ballpoint pens and use to write on different substrates to form well adhesive silver salt-based composite written traces as needed. As a result of high silver salt loading, the trace can be converted into highly conductive silver nanoparticle-based composites after in situreduction. Because of the introduction of adhesive elastomeric rubber, the as-formed conductive composite written trace can not only maintain good adhesion to various substrates but also show good conductivity under various deformations. The conductivity of written traces can be enhanced by repeated writing-reduction cycles. Different patterns can be fabricated by either direct handwriting or hand-copying. As proof-of-concept demonstrations, a typical handwriting heart-like circuit was fabricated to show its capability to work under different deformations, and a pressure-sensitive switch was also manufactured to present pressure-dependent change of resistance.

Image registration, as an important part the computer image processing, has been widely used in such technologies as video compression, 3D reconstruction, image restoration, etc. The paper proposes a new improved Harris algorithm based on corner detection. Based on the characteristics of changes in gray gradient of corners, the paper puts forward the concept of level of similarity of image scale pixel. By detecting the level of similarity between the gray value of the center point of the window and other pixels in the neighborhood, the paper accurately wipes off the pixels without calculating CRF, excludes non-corner pixels and determines the candidate corners. Then calculates the candidate corners through CRF, obtains the final corner, calculates affine transformation coefficient, and completes the image registration. The experiments show that the algorithm can ensure accuracy, and at the same time, reduce calculation to a great extent, and improve the speed of calculation, so that the automatic image registration can be quickly and effectively achieved, which can help the application in real-time processing.