Printed sensors: The key to mass digitisation demands?

Could printed sensors offer the key to meeting the demands of mass digitisation?

From personalised user experiences to warehouse inventory management, data-driven insights are accelerating demand for smarter sensors – and lots of them. Printing sensors could offer an avenue to meet this demand, as the technique enables sensors capable of measuring force, touch, light, gas, temperature and more to be manufactured in large areas at high volumes. However, printed sensors have traditionally struggled to compete with conventional sensing solutions in terms of cost. With mass digitisation demanding greater digital integration, though, the tide could be about to turn.

International Design Engineer asked IDTechX Technology Analyst Dr Jack Howley, author of the market intelligence firm’s recent report “Printed and Flexible Sensors 2024-2034: Technologies, Players, Markets,” whether large-area printed sensors could be the silver bullet to empower the next generation of smart sensing solutions.

EMERGING APPLICATIONS

“In industrial applications, cost is an important driver for the adoption of new sensing solutions,” says Howley. “While printed sensors are poorly positioned to compete on price alone, proactive maintenance and increasing process efficiency are emerging as addressable opportunities. IDTechX predicts that emerging structural integrity monitoring and testing applications will benefit the most from printed sensors.”

So, what real-world application examples could we see leveraging the benefits of printed sensors?

“A great example of this is flexible X-ray photodetectors targeting weld inspection in non-destructive testing,” Howley offers. “Existing photodetector technology is rigid and bulky, prohibiting use in confined spaces. By conforming to pipes, printed X-ray sensors image the entirety of a joint at once, reducing testing time and realising cost savings. Future sensing solutions will see sensors embedded within infrastructure to enable passive monitoring. Key smart infrastructure applications include high sensitivity pressure sensors to detect carbon fibre hydrogen storage tank failure during operation, and non-linear displacement sensors to predict when aging buildings and bridges require decommissioning.”

LARGE AREA SENSING AND MULTIFUNCTIONALITY

According to IDTechX’s report, mass digitisation will see data captured across more surfaces, with large-area sensors offering a logical solution. This is due to the mapping surface interactions of these types of sensors offering greater spatial information and enhanced data granularity than using single-point sensors alone. “To obtain sufficiently large-area sensors, printing becomes somewhat necessary,” the report states, “offering production in vastly expanded dimensions.”

The ability to measure more than one metric at a time is required for many sensing applications. Printing sensors as sheets allows different sensing layers to be stacked and combined with minimal impact on form factor or weight, offering a relatively straightforward way of integrating multifunctional sensing into existing products.

The automotive sector, in particular, is currently showing interest in multifunctional printed sensor growth for applications such as the thermal management of electric vehicle (EV) batteries, the report reveals. Hybrid printed temperature sensors can detect cell hot spots, while pressure sensing layers monitor battery swelling indicative of cell failure and heater layers can provide the means to address these measurements, offering a complete active thermal management solution. In the report, Howley estimates that deployment, charging and discharging optimisations to increase battery capacity and prolong lifetime could be worth up to $3,000 in savings per vehicle.

A NEW THREAT?

However, this opens the door to another debate concerning the disruptive threat posed by hybrid printed sensor technologies to existing sensor industries, as Howley explains.

“Hybrid printed sensors pose the biggest threat where granular and multifunctional performance is as important as the cost of the component,” he says. “Key physical metrics such as touch, pressure, temperature and photodetection are easily combined in slim or flexile form factors using printing methods. Printing enables seamless integration of diverse sensing capabilities with minimal additional spatial requirements. The disruptive potential of hybrid printed sensors is strengthened when delivered alongside complementary printed electronic technologies to offer all-in-one active monitoring solutions. Printed heaters, actuators and haptic elements may be combined with printed sensing layers to afford innovative stimuli-response operation modes.”

In its report, IDTechX predicts that automotive and consumer electronics industries will be most impacted by printed technology, driving the printed sensor market to $960 million by 2034.

“Printed sensors have the greatest potential to disrupt the automotive industry, with large area sensors poised to capitalise on electrification and autonomy trends redefining mobility,” Howley continues. “Printed sensors have the potential to empower the car of the future, from optimised electric battery deployment, augmented and enhanced proximity sensing, to fully interactive and personalised passenger experiences.”

EMERGING MATERIALS

According to Howley, material options are vital in the development of printed sensor technologies and processes. Naturally, innovation in material composition, from metals, polymers, ceramics, nanomaterials, and composites used in sensing layers, to adhesives and flexible substrates, will enable the production of highly tailored sensing solutions.

“Material success in non-sensing applications has an increasing influence on the development of printed sensor technologies and processes,” Howley adds. “Semiconductive polymers used in OLED displays are being leveraged for use in optical and infrared sensing. The successful commercialisation of quantum dots (fluorescent nanoparticles) and in display panels will likely drive similar impact for their use in printed photodetector applications. A prominent target application for printed photodetectors remains on-cell and in-cell fingerprint sensing for whole-display biometric authentication and represents a key growth market behind our 8.6% CAGR forecast for the printed sensor market by 2034.”

PROMISING POTENTIAL

Previously, the inability of printed sensors to meet critical cost, performance, size and reliability thresholds dampened the technology’s progress in key markets. However, as laid out in IDTechX’s report, with mass digitisation driving the need to capture data across more and more surfaces, large-area sensing is “quicky emerging as the higher-valued market differential for printed sensor technology.”

Meanwhile, multifunctional and flexible printed sensors are increasingly desirable for use in the medical and EV industries, and with the most efficient way to combine these properties with large-area sensing being via printed sensors, the outlook for the technology looks favourable indeed. The $960 million anticipated growth in printed sensors will, the report predicts, be largely driven by new opportunities in applications such as battery health management, biometric authentication on flexible displays, and even flexible X-ray medical and industrial imaging.