- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Temperature fiber sensing of Li-ion batteries under different environmental and operating conditions
摘要： In this work, a network of fiber sensors has been developed for real time, in situ, and in operando multipoint monitoring the surface temperature distribution on a smartphone Li-ion battery (LiB). Different temperature and relative humidity conditions are considered, in order to mimic the LiB response in the dry, temperate, and cold climates. In total, the temperature variations that occur in five different locations of the LiB are monitored, during constant current charge and different discharge rates, under normal and abusive operating conditions, performing a thermal spatial mapping of the battery surface. In general, the sensors detect temperature variations according to the voltage signal change and faster variations of voltage usually translate in higher temperature rise at the LiB surface. For instance, under abusive discharge, where the voltage drop is fast, the temperature increases at least twice when compared to the normal operating conditions. Absolute temperature values as high as (65.0 ± 0.1) °C are detected by the optical sensor located near the electrodes, under the higher discharge rate (5.77 C) and dry climate. A thermal gradient is identified from the top to the bottom on the LiB surface during the experimental tests. A lower battery performance is observed when it operates under the cold climate, with maximum temperature variations of (30.0 ± 0.1) °C for the higher discharge rate. These results can be helpful to design of next generation of LiBs, improving a faster cooling in critical areas, in order to reduce accumulated heat and preventing consequences such as thermal runaway and failure.
关键词： Fiber Bragg grating sensors,Temperature monitoring,Abnormal operating conditions,Environment,Safety,Li-ion batteries
更新于2025-09-23 15:23:52
-
[IEEE 2018 International Russian Automation Conference (RusAutoCon) - Sochi (2018.9.9-2018.9.16)] 2018 International Russian Automation Conference (RusAutoCon) - Fiber Optic Technologies for Diagnostic Monitoring of Digital Energy Grids Based on “Smart Grids Plus” Concept
摘要： A modern level of information technologies and computer facilities, as well as an actively developing digitalization of energy grids, allow us to reconsider approaches towards the development and improvement of the functions of automation and control systems for energy installations of various voltage classes. Primarily, it is a medium voltage, as the most common and, in connection with this, the most significant for end users. We propose a new 'Smart Grids Plus' concept for the digital energy grids design. These grids, in addition to the layers of intelligent energy grids and information communication channels, include a layer of diagnostic monitoring based on a passive fiber optic sensor networks. Sensor networks have a hybrid TWDM structure – information exchange channels and integrated fiber optical sensors – core, based on a new technology for address interrogation and multiplexing – special addressable fiber Bragg gratings, combined for arbitrary topologies. Some examples of diagnostic monitoring nets for temperature control of complete switchgear contacts and busbars are considered. Their principles of operation are discussed. The main advantages of these sensor networks are using addressable fiber Bragg gratings simultaneously with sensors and multiplexing elements, and using the PON structure simultaneously with sensor and communication networks.
关键词： fiber optic sensor and passive optical network,complete switchgear contact,smart grids plus,digital energy grids,temperature monitoring,busbar,addressable fiber Bragg grating
更新于2025-09-19 17:15:36
-
Real-time naked-eye recognizable temperature monitoring based on Ho <sup>3+</sup> (or Tm <sup>3+</sup> )-activated NaYF <sub/>4</sub> upconversion nanowires <i>via</i> visual multicolor alteration
摘要： Non-contact thermometry for real-time temperature monitoring is a challenging research topic. Advances in microelectronics and biotechnology demand precise temperature monitoring with novel materials and approaches, where conventional thermometers are burdensome because of employing expensive additional equipment (e.g. spectrometers) and further data processing. Lanthanide-doped upconversion nanomaterials that can convert single near-infrared excitation into multicolor visible emissions open the door for a novel strategy to thermometry. Herein, a real-time naked-eye recognizable color change was achieved based on Ho3+ (or Tm3+)-activated NaYF4 upconversion nanowires, depending on the different spectral sensitivities of the blue, green and red upconversion emissions to temperature. Furthermore, the luminescence color can be also directly modulated by only using 975 nm laser radiation, which extended their application scope. These desirable properties make upconversion nanomaterials promising for temperature monitoring, anti-counterfeiting, and multicolor temperature probing applications with the advantages of being simple, convenient and unreplicable.
关键词： nanowires,naked-eye recognizable,upconversion,temperature monitoring,multicolor alteration
更新于2025-09-19 17:15:36
-
[IEEE 2019 18th International Conference on Optical Communications and Networks (ICOCN) - Huangshan, China (2019.8.5-2019.8.8)] 2019 18th International Conference on Optical Communications and Networks (ICOCN) - In vivo and online temperature monitoring based on fiber Bragg greatings during tumor treatment with nanosecond pulse electric field
摘要： the clinical practice, a compact, in-vivo and online monitoring scheme is an important requirement. A fiber Bragg grating (FBG) sensing system was used to online monitor the temperature at the surface of / inside the liver tissue of a rabbit under nanosecond pulse electric field (nsPEF). Single point measurement between the electrodes and multi-point measurement surrounding one electrode were both carried out. Experimental results show that, due to equally spaced (Δt=0.5 s) 300 ns-pulses with E=20 kV/cm at a repetition rate of 4 Hz, the temperature rise in the rabbit liver tumor usually does not exceed ΔΤ=6℃ for 300 pulses. Theoretical analysis of Joule heating model fits well with the experimental results. Both direct measurements and theoretical modelling demonstrated that nsPEF could not deliver enough energy to heat the treated tissue significantly, thus a hyperthermic effect on the tissue can be excluded during this kind of treatment with much high electric field strength and extremely short duration.
关键词： Fiber Bragg grating,Nanosecond pulse electric field,In-vivo temperature monitoring
更新于2025-09-16 10:30:52
-
The Comparison of Thermal Effects of a 1940‐nm Tm:fiber Laser and 980‐nm Diode Laser on Cortical Tissue: Stereotaxic Laser Brain Surgery
摘要： Background and Objectives: The thermal damage on adjacent healthy structures is always an unwanted consequence of continuous‐wave laser irradiation of soft tissues. To propose a laser as an effective alternative to traditional surgical tools, this photothermal damage due to heat conduction must be taken into account with a detailed laser dosimetry study. Two candidate lasers; a 980‐nm diode and 1940‐nm Tm:fiber were selected for this study. Despite the poor absorption by water, the 980‐nm diode laser has been one of the most widely used lasers in soft tissue surgeries due its good absorption by hemoglobin, which provides good homeostasis. The second laser; the Tm:fiber laser was selected due to its wavelength operating at an absorption peak of water (1,940 nm), which makes it a good candidate for ablation of biological tissues, and it is readily capable of being transmitted through flexible fiber optics to deliver energy to hard‐to‐reach regions. The underlying motivation for the research described in this paper is that with a comprehensive comparison of ablation capabilities and a detailed dose study of infrared lasers operating at different wavelengths and temperature monitoring of the tissue during laser surgery, it may be possible to specify the optimal laser parameters for laser surgery, and propose a treatment alternative to conventional surgical techniques in clinical use. The objectives of this study were to investigate and to compare the thermal effects of 980‐nm and 1940‐nm lasers on cortical tissue in vivo, to find the optimum parameters for laser‐brain‐ablation with minimum thermal damage to the surrounding healthy tissue, and finally, to analyze laser irradiated tissue thermographically and histologically to correlate thermal events and tissue damage with laser irradiation parameters. Study Design/Materials and Methods: Stereotaxic laser brain surgeries were performed on 32 male Wistar rats. A t‐type thermocouple was used to measure the temperature of the nearby tissue at a distance of 1 mm above and 1 mm away from the fiber tip during laser surgery. Cresyl fast violet (CFV) staining was used to expose the thermal extent of laser surgery on cortical tissue. Eight tissue samples from each laser study group were processed for histological analysis and the mean ± standard deviation for thermal damage was reported. Thermal damage was quantified as ablation (thermally removed tissue), severe and mild coagulation (irreversible thermal damage) and edematous (reversible thermal damage) areas with regard to CFV stained slices. The Pearson correlation coefficient was calculated to test if the ablation efficiencies and total damage, and edematous areas were correlated to rates of temperature change. Results: No significant adverse effects were observed during surgeries. We found that both lasers investigated were successful in cortical tissue removal. Our results also revealed that irrespective of the mode of operation, laser wavelength and laser power, there is a strong correlation between the rates of temperature change and ablation efficiencies and a negative correlation between the rate of temperature change and total damage and edematous area. Conclusions: Both lasers investigated were successful in cortical tissue removal. We also reported that when the amount of energy delivered to the tissue was constant, the most important issue was to deliver this energy in a short time to achieve more efficient ablations with less edema around the lesion, regardless of mode of delivery (continuous or pulsed‐modulated mode), but further studies including the healing period after laser surgeries have to be performed to compare the thermal extent of damage comprehensively.
关键词： ablation efficiency,rate of temperature change,980‐nm diode laser,Thulium laser,ablation,real‐time temperature monitoring,Laser brain surgery,cortical tissue
更新于2025-09-11 14:15:04
-
Four-dimensional optoacoustic monitoring of tissue heating with medium intensity focused ultrasound
摘要： Medium-intensity focused ultrasound (MIFU) concerns therapeutic ultrasound interventions aimed at stimulating physiological mechanisms to reinforce healing responses without reaching temperatures that can cause permanent tissue damage. The therapeutic outcome is strongly affected by the temperature distribution in the treated region and its accurate monitoring represents an unmet clinical need. In this work, we investigate on the capacities of four-dimensional optoacoustic tomography to monitor tissue heating with MIFU. Calibration experiments in a tissue-mimicking phantom have confirmed that the optoacoustically-estimated temperature variations accurately match the simultaneously acquired thermocouple readings. The performance of the suggested approach in real tissues was further shown with bovine muscle samples. Volumetric temperature maps were rendered in real time, allowing for dynamic monitoring of the ultrasound focal region, estimation of the peak temperature and the size of the heat-affected volume.
关键词： photoacoustic imaging,thermal treatment monitoring,therapeutic ultrasound,temperature monitoring,optoacoustic tomography
更新于2025-09-10 09:29:36