Nagano, Japan, 27st August 2025 – Hioki E.E. Corporation is proud to announce that our employee has been honored with the Best Paper Award at the IEEE 5th International Conference on Sustainable Energy and Future Electric Transportation (IEEE SEFET).

About IEEE SEFET

IEEE SEFET is an international conference dedicated to the urgent challenges facing modern society: "Sustainable Energy" and "Future Electric Transportation." Organized by the Institute of Electrical and Electronics Engineers (IEEE), a global community of electrical and electronic technology experts, it serves as a crucial platform for discussing the latest research findings, technological innovations, and prospects in the energy and transportation sectors. The 5th IEEE SEFET 2025 was held from July 9 to 12 at the Centre for Energy & Environment, Malaviya National Institute of Technology Jaipur (MNIT Jaipur) in Jaipur, India.

About the Award-Winning Paper

Our engineer, Rahul Sarker, presented the award-winning paper titled "Discrete Luenberger Observer-Based State of Charge Estimation for BMS Under Dynamic Load Conditions." This paper proposes a method for battery management systems (BMS) in electric vehicles to accurately estimate the battery's state of charge (SOC) in real-time. A key feature of this research is its ability to provide stable SOC estimation even under fluctuating load conditions caused by acceleration and deceleration during driving, as well as in noisy environments. The paper was co-authored by Rahul Sarker, along with Christiaan Johannes Fourie and Takumi Mori, who are also affiliated with our company.

Left: Scenes from the IEEE SEFET 2025 venue. Right: Best Paper Award.

Comments from the Award Recipient

I am truly honored to receive the Best Paper Award at IEEE SeFet-2025. This recognition is a meaningful milestone in my professional journey and reflects the value of pursuing practical and impactful research in battery technology in the future. This achievement would not have been possible without the collective support, resources, and encouragement that inspired me throughout the research. I look forward to continuing to contribute to technological advancement and solving real-world challenges in energy and measurement.

Introduction of the Award Recipient Rahul Sarker

• Institute of Electrical and Electronics Engineers (IEEE):
  The world's largest and most authoritative non-profit professional organization in the fields of electrical engineering, electronics, information technology, and related broad technological areas. With over 400,000 members in more than 160 countries and regions, its mission is to advance technology for the benefit of humanity.


• BMS (Battery Management System):
  An electronic control system designed to safely and efficiently operate and manage batteries, such as lithium-ion batteries.


• SOC (State of Charge):
  An indicator that represents the current charge level of a battery.


• Luenberger Observer:
  A mathematical technique proposed by American control engineer David G. Luenberger. In control engineering, it is used to estimate the internal states of a system (e.g., battery's state of charge).

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