NGK and Renesas collaborate on maintenance-free IoT

  • March 17, 2021
  • Steve Rogerson

Japanese companies NGK Insulators and Renesas Electronics are jointly developing maintenance-free IoT devices powered by energy harvesting.

As the first phase of collaboration, the two companies have jointly developed a reference design for a wireless air quality sensing system that will contribute to realising a decarbonised society. The system was developed by combining NGK’s EnerCera battery series and Renesas’ RE family of low-power microcontrollers (MCUs).

Data collection and use are considered to be the most effective means of realising a productive life or addressing social issues. Meanwhile, actions to achieve the decarbonisation of society have been gathering momentum globally.

For example, Japan and other countries around the world have adopted the goal of achieving net zero greenhouse gas emissions by 2050. Therefore, these countries will need to reduce their power consumption even as they deploy numerous IoT devices for data collection.

To realise such a society, there is a need to develop maintenance-free IoT devices that can be powered by trace amounts of electric power obtainable from energy sources in the environment, such as peripheral light, heat and vibration energy. It also requires a device not to need battery replacement.

The EnerCera is a lithium-ion rechargeable battery with a high capacity, low resistance and long life despite having a compact, thin body. The series is suitable for use as a power source for maintenance-free IoT devices, since it can charge itself with a weak current and output an intermittent large current to drive functions such as sensing and communications.

To power a device with the electric power stored in the battery, an MCU that links the battery with sensors, communication ICs and other components is needed. For this reason, NGK has developed a reference design for promoting the adoption of maintenance-free IoT devices using Renesas’ RE MCUs.

“We are confident that the combination of NGK’s battery technology and Renesas’ ultra-low power consumption technology will accelerate the widespread adoption of battery maintenance-free IoT devices,” said Makoto Mizokuchi, head of low power products at Renesas.

As the first phase of the collaboration, NGK and Renesas jointly developed a reference design for wireless outdoor air quality sensing powered by solar cells. Monitoring pollution levels in outdoor air provides insights on the associated health effects from elevated levels. Conventional sensing systems have problems such as requiring power cables due to their large power consumption and thus being restricted on where they could be installed.

“I’m convinced that NGK’s collaboration with Renesas will promote the development of maintenance-free IoT devices, thereby helping to solve social issues while realising a decarbonised society,” said Iwao Ohwada, vice president at NGK.

The combination of low-power MCUs and low resistance, high-capacity batteries should enable constant measurement of outdoor air quality indexes at all times, even with only trace amounts of intermittent electric power obtainable from the solar cells. This will allow monitoring of the degree of atmospheric pollution without having to devote time and effort to power cable wiring and battery replacement. The system can also support long-distance radio communications such as low-power wide-area (LPWA) network technologies, enabling centralised management of measurements from numerous sensors.

Not only for environmental monitoring but also other fields, NGK and Renesas will continue to develop reference designs to realise the widespread adoption of maintenance-free IoT devices that combine their batteries and MCUs.

Founded in 1919, NGK today is active in more than 20 countries worldwide, in business including mobility, energy, IT and industry.