Permanent, Wireless Self-charging System Using NIR Band
October 10, 2018 | KAISTEstimated reading time: 2 minutes
As wearable devices are emerging, there are numerous studies on wireless charging systems. Here, a KAIST research team has developed a permanent, wireless self-charging platform for low-power wearable electronics by converting near-infrared (NIR) band irradiation to electrical energy. This novel technology can be applied to flexible, wearable charging systems without needing any attachments.
Colloidal-quantum-dots (CQDs) are promising materials for manufacturing semiconductors; in particular, PbS-based CQDs have facile optical tunability from the visible to infrared wavelength region. Hence, they can be applied to various devices, such as lighting, photovoltaics (PVs), and photodetectors.
Continuous research on CQD-based optoelectronic devices has increased their power conversion efficiency (PCE) to 12%; however, applicable fields have not yet been found for them. Meanwhile, wearable electronic devices commonly face the problem of inconvenient charging systems because users have to constantly charge batteries attached to an energy source.
A joint team led by Professor Jung-Yong Lee from the Graduate School of Energy, Environment, Water and Sustainability and Jang Wok Choi from Seoul National University decided to apply CQD PVs, which have high quantum efficiency in NIR band to self-charging systems on wearable devices.
They employed a stable and efficient NIR energy conversion strategy. The system was comprised of a PbS CQD-based PV module, a flexible interdigitated lithium-ion battery, and various types of NIR-transparent films.
The team removed the existing battery from the already commercialized wearable healthcare bracelet and replaced it with the proposed self-charging system. They confirmed that the system can be applied to a low power wearable device via the NIR band.
There have been numerous platforms using solar irradiation, but the newly developed platform has more advantages because it allows conventional devices to be much more comfortable to wear and charged easily in everyday life using various irradiation sources for constant charging.
With this aspect, the proposed platform facilitates more flexible designs, which are the important component for actual commercialization. It also secures higher photostability and efficient than existing structures.
Professor Lee said, “By using the NIR band, we proposed a new approach to solve charging system issues of wearable devices. I believe that this platform will be a novel platform for energy conversion and that its application can be further extended to various fields, including mobiles, IoTs, and drones.”
Figure 1. a) Conceptual NIR-driven self-charging system including a flexible CQD PVs module and an interdigitatedly structured LIB. b) Photographic images of a conventional wearable healthcare bracelet and a self-charging system-integrated wearable device.
Figure 2. Illustration of the CQD PVs structure and performance of the wireless self-charging platform.
Suggested Items
I-Connect007 Editor’s Choice: Five Must-Reads for the Week
05/03/2024 | Nolan Johnson, I-Connect007This week’s most important news is strategic—and telling. When one puts together the IPC industry reports, we simply have to include the recent conversation with Shawn DuBravac and Tom Kastner. On the design side, check out the latest “On The Line With…” podcast featuring Brad Griffin from Cadence Design Systems, discussing SI and PI in the realm of intelligent system design.
Industrial PC Market Size to Record $1.75 Billion Growth from 2023-2027
05/03/2024 | PRNewswireThe global industrial pc market size is estimated to grow by USD 1.75 billion from 2023 to 2027, according to Technavio. This growth is expected to occur at a Compound Annual Growth Rate (CAGR) of almost 6.29% during the forecast period.
Real Time with… IPC APEX EXPO 2024: Sigma Engineering's Recycling and Regeneration Systems for PCB Etching
05/02/2024 | Real Time with...IPC APEX EXPOEvan Howard of Schmoll America interviews Kristoffer Bjorklund, Sigma Engineering's supply chain manager. We learn about Sigma's recycling and regeneration systems for PCB industry etching and the benefits and challenges of implementing these systems in existing factories.
Boeing T-7A Red Hawk Triples Progress
05/01/2024 | BoeingThe Boeing T-7A Red Hawk achieved three recent milestones, propelling the advanced pilot trainer for the U.S. Air Force forward.
Merlin Flex invests in New Schmoll Direct Imaging System
04/30/2024 | Merlin Flex LtdMerlin Flex has fully installed and commissioned its 2nd Schmoll MDI Direct Imaging system. This new machine includes a twin bed, 4 head system which enhances Merlin Flex’s direct imaging capability for its 1.4M long flexible circuits.