Issue link: https://iconnect007.uberflip.com/i/948150
54 SMT007 MAGAZINE I MARCH 2018 7. Stencil Design Task Group 5-21e, "Stencil Design Guidelines," IPC-7525B, October 2011. 8. M. Rösch, J. Franke, C. Läntzsch, "Charac- teristics and Potentials of Nano-Coated Stencils for Stencil Printing Optimization," Proceedings of SMTA International, October 2010. 9. M. Kelly, W. Green, M. Cole, R. Kellmann, "Plasma Stencil Treatments: A Statistical Eval- uation," Proceedings of SMTA International, October 2013. 10. C. Shea, M. Bixenman, D. Carboni, B. Sandy-Smith, G. Wade, R. Whittier, J. Perault, E. Hansen, "Quantifying the Improvements in the Solder Paste Printing Process from Stencil Nano - coatings and Engineered Under Wipe Solvents," Proceedings of SMTA International Conference on Soldering and Reliability, May 2014. 11. T. Lentz, "Performance Enhancing Nano-Coatings: Changing the Rules of Stencil Design," Proceedings of SMTA International, September 2014. 12. C. Salewski, J. L'Heureux, "Highly Accu- rate 3D Solder Paste Inspection Compar- ing Nano Coated Stencils with Non-Coated Results," Proceedings of SMTA International, September 2014. 13. J. Schake, M. Whitmore, C. Ashmore, "Stencil Aperture Design Considerations for 0.3 CSP Ultra-Fine Pitch Printing," Proceedings of SMTA International, October 2013. 14. M. Whitmore, C. Ashmore, "The Next Big Challenge for Stencil Printing—Sub 0.5 Area Ratio Apertures," Proceedings of SMTA International, September 2014. Editor's Note: This article originally published in the 2016 SMTA International Conference Proceedings. Jeff Schake is a senior engineer, Advanced Print Technologies Printing Solutions, of ASM Assembly Systems LLC. Mark Whitmore is the senior manager, Advanced Print Technologies Printing Solutions, of ASM Assembly Systems LLC. A New Approach to Rechargeable Batteries A type of battery first invented nearly five decades ago could catapult to the forefront of energy storage technologies, thanks to a new finding by research- ers at MIT. The battery, based on electrodes made of sodium and nickel chloride and using a new type of metal mesh membrane, could be used for grid-scale installations to make intermittent power sources such as wind and solar capable of delivering reliable baseload electricity. Although the basic battery chemistry the team used, based on a liquid sodium electrode material, was first described in 1968, the concept never caught on as a practical approach because it required the use of a thin membrane to separate its molten compo- nents, and the only known material with the needed properties for that membrane was a brittle and frag- ile ceramic. After experimenting with various compounds, the team found that an ordinary steel mesh coated with a solution of titanium nitride could perform all the func- tions of the previously used ceramic membranes, but without the brittleness and fragility. The use of the new type of membrane can be applied to a wide variety of molten-electrode battery chemistries and opens up new avenues for battery design. The findings were reported in the journal Nature Energy, by a team led by MIT professor Donald Sado- way, postdocs Huayi Yin and Brice Chung, and four others.