DC Power Line Communication (PLC) on 868 MHz and 2.4 GHz Wired RF Transceivers

Efficient management through monitoring of Li-ion batteries is critical to the progress of electro-mobility and energy storage globally, since the technology can be hazardous if pushed beyond its safety boundaries. Battery management systems (BMSs) are being actively improved to reduce size, weight, and cost while increasing their capabilities. Using power line communication, wireless monitoring, or hybrid data links are one of the most advanced research directions today. In this work, we propose the use of radio frequency (RF) transceivers as a communication unit that can deliver both wired and wireless services, through their superior analog and digital signal processing capability compared to PLC technology. To validate our approach computational simulation and empirical evaluation was conducted to examine the possibility of using RF transceivers on a direct current (DC) bus for wired BMS. A key advantage of this study is that it proposes a flexible and tested system for communication across a variety of network scenarios, where wireless data links over disrupted connections may be enabled by using this technology in short-range wired modes. This investigation demonstrates that the IEEE 802.15.4-compliant transceivers with operating frequencies of 868 MHz and 2.4 GHz can establish stable data links on a DC bus via capacitive coupling at high data rates

Impact of Li-Ion Battery on System’s Overall Impedance and Received Signal Strength for Power Line Communication (PLC)

In anticipation of the hybrid utilisation of the radio frequency (RF) wireless transceiver technology embedded in future smart Li-ion battery cells to deliver hybrid links based on power line communication (PLC) and wireless connections, herein we present an empirical high-frequency investigation of the direct current (DC) bus. The focus is to determine, via statistical tools including correlation coefficient (CC), root mean squared error (RMSE) and feature selective validation (FSV) method, the impedance and signal change impact on a possible communication link when fully charged cells are present or completely missing from the bus. Moreover, to establish if technological differences may be accounted for during the empirical experiments, Li-ion cells from two different manufacturers were selected and connected via three subsequent capacitive couplings of 1 µF, 1 nF and 1 pF. According to a methodical comparison by employing CC, RMSE, and FSV over the measured impedance and signal attenuation, this study has shown that the physical DC network is the dominant impedance at high frequencies and that the signal attenuation on the DC line supports communication in the investigated spectrum. The reported findings are critical for in situ hybrid PLC and wireless communication implementation of BMS for Li-ion systems supported through only one RF transceiver

Power Electronics and Energy Management for Battery Storage Systems

The deployment of distributed renewable generation and e-mobility systems is creating a demand for improved dynamic performance, flexibility, and resilience in electrical grids. Various energy storages, such as stationary and electric vehicle batteries, together with power electronic interfaces, will play a key role in addressing these requests thanks to their enhanced functionality, fast response times, and configuration flexibility. For the large-scale implementation of this technology, the associated enabling developments are becoming of paramount importance. These include energy management algorithms; optimal sizing and coordinated control strategies of different storage technologies, including e-mobility storage; power electronic converters for interfacing renewables and battery systems, which allow for advanced interactions with the grid; and increase in round-trip efficiencies by means of advanced materials, components, and algorithms. This Special Issue contains the developments that have been published b researchers in the areas of power electronics, energy management and battery storage. A range of potential solutions to the existing barriers is presented, aiming to make the most out of these emerging technologies

Improved testing strategies from standards for new growing battery applications in the industrial and e-mobility sectors

In the current energy challenges, related to both climate change and the sudden rise in energy prices, batteries plays a key role in providing and storing energy. Before batteries are sent to market, the batteries are repeatedly subjected to different types of tests since it is crucial to verify that the performance and safety of these technologies are ensured in the different applications. This master’s thesis is dedicated to improving battery testing methodologies to address the growing industrial and e-mobility sectors. By identifying and tackling gaps in existing international standards, this research aims to enhance the link between battery testing and real-life operation of batteries, with the final objective of developing an adaptable testing framework for AVL, a leading powertrain systems company. The study investigates the factors driving battery testing, the impact of diverse applications on battery characteristics, and the need for refined testing strategies. The methodology includes a comprehensive background study of battery behavior, a review of battery performance parameters, and an analysis of prevailing testing procedures. The research results in the development of an algorithm for adaptable synthetic duty cycles, along with new testing procedures for capacity and cycle lifetime tests. The optimization of testing procedures enables AVL to take a prominent role in electrification and battery testing, offering more accurate and effective testing solutions. Ultimately, this contributes to a more sustainable industry by facilitating the secure and efficient use of battery technologies in emerging applications, particularly within the transport secto

In-situ instrumentation of cells and power line communication data acquisition towards smart cell development

The internal core temperature of cells is required to create accurate cell models and understand cell performance within a module. Pack cooling concepts often trade off temperature uniformity, vs cost/weight and complexity. Poor thermal management systems can lead to accelerated cell degradation, and unbalanced ageing. To provide core temperature an internal array of 7 thermistors was constructed; these in conjunction with cell current, via bus bar mounted sensors, and voltage sensor measurements, we have developed instrumented cells. These cells are also equipped with power line communication (PLC) circuitry, forming smart cells. We report upon data from these miniature sensors during cell cycling, demonstrating successful operation of the PLC system (zero errors compared to a reference wired connection) during typical cell cycling (C/2 discharge, C/3 charge) and the application of automotive drive cycle, providing a transient current test profile. Temperature variation within the cell of approximately 1.2 °C gradients, and variation of >2.8 °C during just 30 min of 2C discharging demonstrate the need for internal sensing and monitoring throughout the lifetime of a cell. Our cycling experimental data, along with thorough cell performance tracking, where typically <0.5% degradation was found following instrumentation process, demonstrate the success of our novel prototype smart cells

Battery Testing for Emerging Battery Applications in Industrial and E-mobility Sectors

In the current energy challenges, related to both climate change and the sudden rise in energy prices, batteries plays a key role in providing and storing energy. Before batteries are sent to market, the batteries are repeatedly subjected to different types of tests since it is crucial to ver- ify that the performance and safety of these technologies are ensured in the different applications. This master’s thesis is dedicated to improving battery testing methodologies to address the growing industrial and e-mobility sectors. By identifying and tackling gaps in existing inter- national standards, this research aims to enhance the link between battery testing and real-life operation of batteries, with the final objective of developing an adaptable testing framework for AVL MTC Motortestcenter AB, a leading powertrain systems company. The study investigates the factors driving battery testing, the impact of diverse applications on battery characteristics, and the need for refined testing strategies. The methodology includes a comprehensive background study of battery behavior, a review of battery performance param- eters, and an analysis of prevailing testing procedures. The research results in the development of an algorithm for adaptable synthetic duty cycles, along with new testing procedures for capacity and cycle lifetime tests. The optimization of testing procedures enables AVL to take a prominent role in electrification and battery testing, offering more accurate and effective testing solutions. Ultimately, this contributes to a more sustainable industry by facilitating the secure and efficient use of battery technologies in emerg- ing applications, particularly within the transport sector.Objectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructur

Battery configuration dependence to power line communication using high-order quadrature amplitude modulation

Power line communication (PLC) within future smart batteries facilitates the communication of high fidelity sensor data between smart cells and external systems, with application areas including intelligent vehicles and smart grids. This interconnected PLC system of smart cells will enhance cell utilisation and safety through cell-to-cell coordination at a system level, leveraging the existing bus bar within the battery and eliminating the need for additional wire harnesses. This paper studies the performance of a PLC system operating at carrier frequencies of 10 MHz to 6 GHz within four distinct configurations of lithium-ion batteries. This assessment focuses on changes in scattering parameters and data transmission error ratios. Furthermore, quadrature amplitude modulation (QAM) orders of up to 1024 are investigated for their viability within such environments. The results indicate that the addition of cells in parallel increases error ratios with high-order QAM, and that this effect varies substantially with carrier frequency. Using QAM increases data throughput, allowing for data transfers within large-scale battery systems without PLC bus bandwidth saturation. A prospective centre frequency of 3650 MHz allows for a wide bandwidth of 300 MHz and 1024-QAM with little signal attenuation and data error. At this frequency, the need for signal repeaters and higher signal output power is reduced. These results are used to determine the most suitable arrangement of cells within a smart battery with consideration of the PLC performance. The preliminary performance of a large-scale battery system with PLC in-situ could be derived from the findings in this research based upon the four battery configurations tested

Two-Dimensional Nanomaterials and Their Composites for Electrochemical Detection of Toxic Mercury Ions in Water

The presence of trace amounts of mercury ion (Hg2+) in drinking water has a detrimental effect on human health. The development of an electrochemical sensor for Hg2+ detection is still challenging to obtain ultra-trace sensitivity, excellent selectivity, wide Linear Detection Ranges (LDRs), and ultra-low detection limit. This work presents an electrochemical sensor based on two-dimensional nanomaterials and their composites for the enhanced sensing of Hg2+ in water. Graphene oxide (GO)-silver nanowires (AgNWs) composite and metallic 1T phase tungsten disulfide (WS2) microflowers were utilized for the fabrication of electrochemical sensors using drop-casting. Under the optimized experimental conditions, the GO-AgNWs composite modified sensor showed a high sensitivity of ~ 0.29 μA/nM and linear response in the range of 1-70 nM toward Hg2+, whereas 1T-WS2 microflowers modified sensor showed excellent sensitivities of ~ 15.9 μA/μM, 2.54 μA/μM, 13.84 μA/μM, and 0.04646 μA/μM toward Hg2+ with LDRs of 1- 90 nM, 0.1-0.4 μM, 0.5-1.0 μM, and 0.1-1.0 mM, respectively. An ultra-low detection limit of 0.1 nM and 0.0798 nM or 79.8 pM toward Hg2+ was obtained by GO-AgNWs composite and 1T-WS2 modified sensors, which are well below the guideline value recommended by the World Health Organization and the United States Environmental Protection Agency. The sensors exhibited excellent selectivity for Hg2+ against other heavy metal ions including Cu2+, Fe3+, Ni2+, Pb2+, Cr3+, K+, Na+, Ag+, Sn2+, and Cd2+. The thus obtained excellent sensitivity and selectivity with wide LDRs and ultra-low detection limits can be attributed to the synergistic effect of GO and conductive AgNWs, high conductivity, large surface area microflower structured 1T-WS2, and the complexation of Hg2+ ions with sulfur (S2-) and GO. In addition to good repeatability, reproducibility, and stability, these sensors showed practical feasibility of Hg2+ detection in tap water suggesting a promising device for real applications