Battery to provide on-chip power

The holographically patterned microbattery (photo: University of Illinois)

The magazine Design Products and Applications in the UK has reported that researchers have combined 3D holographic lithography and 2D photolithography to produce a 3D micro-battery suitable for large-scale ‘on-chip’ integration. “This 3D micro-battery has exceptional performance and scalability, and we think it will be of importance for many applications,” says Professor Paul Braun of the University of Illinois at Urbana-Champaign where the work was carried out. “Micro-scale devices typically utilise power supplied off-chip because of difficulties in miniaturising energy storage technologies.

“A miniaturised high-energy and high-power on-chip battery would be highly desirable for applications including autonomous micro-scale actuators, distributed wireless sensors and transmitters, monitors, and portable and implantable medical devices,” Braun adds.

Hailong Ning, a graduate student at Illinois and author of a paper on the work published in the Proceedings of the National Academy of Sciences, says that due to the complexity of 3D electrodes, it is generally difficult to realise such batteries, let alone the possibility of on-chip integration and scaling.

“In this project, we developed an effective method to make high-performance 3D lithium-ion micro-batteries using processes that are highly compatible with the fabrication of microelectronics,” says Ning. “We utilised 3D holographic lithography to define the interior structure of electrodes and 2D photolithography to create the desired electrode shape.”

Enabled by a 3D holographic patterning technique – where multiple optical beams interfere inside the photoresist creating a desirable 3D structure – the battery possesses well-defined, periodically structured porous electrodes, that facilitates the fast transport of electrons and ions inside the battery, offering supercapacitor-like power.

“Although accurate control on the interfering optical beams is required to construct 3D holographic lithography, recent advances have significantly simplified the required optics, enabling creation of structures via a single incident beam and standard photoresist processing,” says Professor John Rogers who worked with Braun’s team. “This makes it highly scalable and compatible with micro-fabrication.”

This article was first published by Les Hunt on “DPA on the net”, www.dpaonthenet.net.

New design of Variable Speed Starter

The new PowerXL DE1 Variable Speed Starter (VSS) from Eaton made a big impression at the Hannover Messe trade fair. The German Industriepreis 2015 panel of professors, scientists, industry experts and specialist journalists recognized that the PowerXL DE1 VSS fills a gap in the market, for a new device class for motor control that will be particularly useful for helping to increase energy efficiency in applications where fixed-speed starters were previously used. So the Eaton PowerXL DE1 VSS was awarded the Industriepreis 2015 in the Electrical Engineering category.

Government efficiency requirements such as those set out in the ErP Directive, combined with increasing levels of machine automation have seen a significant growth in the use of applications with variable speeds. However, conventional variable speed drives are often too complex for these applications, whilst starters don’t provide the option to control speed. The PowerXL DE1 VSS provides machine and system builders with a cost-efficient and highly reliable new device class for motor control that will be particularly useful for helping them to increase energy efficiency in applications where fixed-speed starters were previously used. The PowerXL DE1 VSS fills a gap in the market, and this is recognized by the Industriepreis award, which recognizes ideas and products which are innovative, production-ready and modern, as well as that help users be more profitable and efficient.

The VSSs have been designed for straightforward ‘out of the box’ operation without the need for adjustments or parameter setting. At the same time, users have at their disposal a universal configuration module that allows the most important parameters to be set using only a screwdriver – no keyboard, software or manual are needed. This means they require up to 80% less commissioning time and cost up to 70% less to install than conventional VSDs.