Despite rapid advancements in medical technology, healthcare professionals still grapple with the question: how can we make patients as comfortable as possible? While this is a multifaceted issue involving many potential solutions, a simple approach that appears to ensure healthier and faster recovery is often overlooked—wireless charging. Whether integrated into the operating room or implanted in medical devices, wireless charging technology has the potential to enhance the patient experience from admission to discharge.
Wireless charging has indeed brought many conveniences to portable medical devices, which traditionally require regular battery replacements. Integrating wireless charging into medical devices for different application scenarios can better leverage the advantages of wireless charging. Dr. Wen Sihua, Marketing and Application Manager of Battery Management Products (BMS) for Greater China at Texas Instruments, explained that, for example, hearing aids can be made smaller after integrating wireless charging, and charging can be achieved simply by placing them in an electromagnetic induction box. Before this, the best compact solution was only USB charging. The application of wireless charging technology in portable medical devices still requires a case-by-case approach. For example, the non-planar mechanical shape of many devices poses challenges to electromagnetic shielding, affecting wireless charging efficiency and radiation safety. In addition, medical applications, such as wearables, have a very low dependence on industry standards.
Current expectations for wireless charging applications largely focus on long-range wireless power transfer. However, the mainstream applications remain consumer-grade smartphones, tablets, smartwatches, some wireless Bluetooth speakers, and more traditional electric toothbrushes. Texas Instruments' wireless charging receivers reportedly fall into two categories: power supply receivers offering 5V/1A or 5V to 10V, and Direct Charge receivers for direct charging. Their product focus is primarily on consumer-grade wearable devices that offer both versatility and high performance.
Wireless charging uses the principle of near-field electromagnetic induction to transfer energy from the charging pad to the portable device. Over a constantly changing distance, the transmitter coil (Tx) in the charging pad transfers energy to the receiver coil (Rx) embedded in the portable device, such as a mobile phone. When powered on, the transmitter/primary coil in the charging pad generates an electromagnetic field similar to a traditional transformer, inducing a current that flows through the secondary coil in the portable device. (The charging pad has a power conversion circuit that converts electrical energy into an electromagnetic field. At the receiver, a power pickup unit converts the electromagnetic field back into electrical energy to charge the device's battery.) The transmitter and receiver communicate with each other to control the charging process.
Vishay Dale Electronics' IWAS series Qi wireless charging receiver coils/shrouds are among the first commercially available wireless charging coils available for devices compliant with WPC specifications. The IWAS series achieves efficiencies of 70% or higher and provides a high-permeability shroud for the receiver coil, blocking charging magnetic flux and preventing damage to sensitive components or the battery. The performance of the IWAS series wireless charging receiver coils/shrouds is not adversely affected by permanent magnets.
With the rising incidence of chronic diseases, the use of implantable medical devices, such as pacemakers, is also increasing, assisting in the monitoring, diagnosis, and treatment of patients. These devices offer patients the freedom to live their daily lives outside the hospital ward. However, implantable devices typically require invasive procedures for routine maintenance and battery replacements. The next step towards true patient freedom is to reduce these procedures, which are not only uncomfortable for patients but also costly in the long run. Wireless power allows for charging of the implanted device simply by placing a receiver under the skin. Advances in wireless charging technology also enable remote monitoring of implanted devices, allowing doctors and patients to access biometric data in real time to ensure optimal treatment outcomes.
Operating rooms are cold, sterile environments, and a safe, sterile environment is one of the most important factors for successful surgery. More and more IoT technologies and new devices are being introduced into operating rooms, but many of these devices have charging ports, which makes sterilization difficult, leading to additional costs and time. Operating rooms equipped with wireless charging technology can avoid these problems by using portless devices with embedded wireless charging capabilities, making them easier to sterilize than wired operating rooms. Eliminating wires in the operating room also improves the mobility of surgeons and other caregivers in the environment, while eliminating the risk of anyone tripping over wires.
