Search

Flexible Li-ion batteries (LIBs) have a strong oncoming consumer market demand for use in wearable electronic devices, flexible smart electronics, roll-up displays, electronic shelf labels, active radio-frequency identification tags, and implantable medical devices. This market demand necessitates research and development of flexible LIBs in order to fulfill the power requirements of these next-generation devices. In this study, the performance of semi solid anode for flexible Lithiumion battery was investigated through a mathematical model in order to reduce the number of experiments and to achieve the desired energy capacity of the battery. This model is a multiphysics three-dimensional heterogeneous model where all necessary transport phenomena including the charge and mass transfer and electrochemical reactions are considered at continuum mechanics level. COMSOL Multiphysics software is used to solve governing equations numerically using a finite element method. This model is for a half-cell simulation, and by using experimental results obtained in the lab. The maximum specific discharge capacity of the simulation Graphite/Li half-cell and LCO/Li reached up to 248(mAh/g) and 128(mAh/g), respectively, compared to the values received in the experimental test of ∼240 (mAh/g) for Graphite/Li and 120 (mAh/g) for LCO/Li. Overall, the simulation results were in acceptable agreement with those of the experiment. Parametric study was also performed to study the effect of adjustable parameters on the performance of both half cells. The difference in the discharge capacity was observed showing higher values at higher cell temperature and lower c-rate.

The behavior of retired lithium-ion battery (LIB) from its first-life application such as electric vehicles and electric aircraft for its second-life in a solar photovoltaic (PV) grid-tied system for residential applications is studied through mathematical modeling. The rate of capacity-fade and the useful remaining life of the retired- or used-LIB particularly investigated in this paper. The first part of this paper presents the optimal size of a small-scale battery energy storage system (BESS) to store a part of the solar energy for postponing consumption in the near future for a typical home in Akron, Ohio. The LIBs in this study has lithium nickel manganese cobalt oxide (NMC) chemistry. The sizing is determined based on a set of PV panels, power rate of the BESS, and hourly data of temperatures, irradiation and home demand load. Using PVWatts® Calculator from National Renewable Energy Laboratory (NREL), the hourly PV performance data of the PV generation system is obtained. In this study, the home is connected to the grid, but the net energy usage from the grid in one year is zero. The duty-cycle of the PV generation is obtained in order to design a LIB energy storage system using calculations of the PV system hourly energy production. The difference between the residential home demand and PV generation is used to evaluate the excess energy that charges the battery and is sold to the electric grid. In the second part, the retired- or the used-battery degradation rate and its remaining useful second-life in the BESS are estimated using an empirical battery model. This model includes the capacity-fade of the LIB for both first- and second-life applications under different operating and environmental conditions. It is shown that a used-LIB from first-life applications is still suitable to be used for this system. The results show that the investigated used-LIB is capable of being in-service for another 10 years in the PV system for residential application. The results of this paper can potentially reduce the battery cost for electric vehicles and electric aircraft because the retired battery from these applications have still value to serve for another applications such as PV system for residential homes. Since this study is based on mathematical modeling, several assumptions have been made in the model. Although the results of mathematical modeling is very promising, these results should be proved experimentally. The experimental studies is out of the scope of this paper.

Among many types of all-solid-state lithium batteries (ASSLBs), the one based on argyrodite crystalline electrolyte is considered as one of the most promising batteries because of their safety and high energy density. Significant efforts have been devoted toward developing argyrodite-type ASSLBs, but the commercialization of these batteries still needs to resolve some scientific and technical problems. Two problems that need to be addressed are reducing the interfacial resistance between the electrolyte and electrode active materials and minimizing the reaction between the electrolyte and electrode active materials. One method to solve these two problems is to coat the electrode active material with a material which is compatible with argyrodite electrolyte. The aims of this paper are (1) to compare two methods of synthesizing and coating of cathode active material and (2) to evaluate the capacity and cycling performance of the coated active material. In this study the emphasis is on lithium niobate (LiNbO3) as the coating material and LiNi0.85Mn0.1Co0.05O2 (NMC) as the nickel-rich cathode active material.

A geothermal heat exchanger (GHE) uses the geothermal energy for heating or cooling of residential places during winter or summer. Two different designs of GHEs, the straight-pipe and coiled-pipe designs, are evaluated in this study, and the effect of nanofluid as the working fluid is investigated. For this purpose, a mathematical model is developed, validated, and used to predict the temperature gain, heat gain, exergy gain, and pressure loss of the working fluid for different concentration of additive ceramic nanoparticles (Al2O3 and MgO) into the working fluid. It is shown that the coiled-pipe design has better performance compared to the straight-pipe design for GHEs. It also shown that how the temperature, heat gain and exergy gain change with increasing the additive nanoparticles into the base-fluid (water), while the pressure loss does not change significantly. The temperature gain increases about 60% when the volume fraction of nanoparticles in the base-fluid reaches 2%. This also helps to improve the natural circulation of working fluid and the GHE may not need a circulating pump to run at low flow rates. It is also shown that the additive MgO nanoparticles is more effective than Al2O3 nanoparticles to improve the GHE performance.

Some lithium-ion batteries (LIBs) applications are mobile and stationary energy storage systems such as electric vehicles (full electric, hybrid and plug-in hybrid), different types of aircraft, and renewable energy technologies. LIBs can play a tremendous role in replacing the considerable dependence of nations on fossil fuels due to the high storage energy density of renewable energy alternatives. They also have a high cost associated with the material costs, as well as the other manufacturing costs. The environmental impact of manufacturing and disposing lithium-ion batteries has triggered actions to reduce the resulting impact by recycling batteries. Degradation of LIBs is always a concern for any application. To predict the life of cells correctly, it is more efficient to cover all mechanisms leading to capacity-fade or resistance growth. This study discusses the degradation rate of a LIB at two stages of life for both first- and second-uses. Empirical models can be used to measure capacity-fade, resulting from the battery degradation. The duty-cycle of the commercial LIB for a typical passenger aircraft, such as the Bombardier CRJ200, was obtained. For this purpose, the velocity and altitude of the aircraft were monitored during a typical flight, and the instantaneous mechanical power of the aircraft was obtained by modeling. Then, the duty-cycle of a LIB cell in the battery pack was yielded. The life prediction of the LIB in electrical energy storage for aircraft was studied. Although many studies have been done to evaluate performance and durability of LIB cells and packs for vehicle applications, there are very few studies of the application of LIBs in electric and hybrid aircraft. The degradation rate of the battery for a typical lightweight passenger aircraft with a flight range of less than 1000 km was then presented by using an empirical modeling method. The results showed that the A123 battery (20 Ah) degraded after 6 months at 45°C and 80% State of charge (SOC) and after 1.8 years at 45°C and 80% depth of discharge (DOD) by assuming that the battery should be retired when the rate of degradation reaches 15% of its nominal capacity. It was found that a retired first-use LIB cell is durable enough to be utilized in many second-use applications which can have lots of environmental benefits. Several items related to second use of LIBs will be discussed in this paper.

Steel pipeline in the oil and gas industry is subject to complex stress-strain due to soil movement along the pipes and internal pressure. The induced longitudinal strains due to soil movement along the pipe and the induced elasto-plastic local strain distribution are shown to impact the pipeline corrosion. In this work, we study the effect of defect geometry and density along the pipe on the local stress-strain distribution and subsequent local corrosion activity. Small strain von Mises yielding criteria is used and corrosion potential, anodic current density, and cathodic current density are characterized and used for this study by looking at the center to edge ratio.

Solid state electrolytes are promising materials for use in lithium-ion batteries for applications in electric vehicles and aircraft. One of the most promising solid electrolytes are the Argyrodite materials, Li6PS5X(X = Cl, Br, I). Among Argyrodites, Li6PS5Cl0.5Br0.5 crystalline material has high ionic conductivity, good processability and excellent electrochemical stability. It is reported in literature that the pelletization pressure and operating pressure and temperature significantly affect the ionic conductivity of argyrodite electrolytes and the cell performance. The focus of this paper is on Li6PS5Cl0.5Br0.5, a crystalline electrolyte material, and the goals are to systematically investigate effects of the pelletization pressure and operating pressure and temperature on the ionic conductivity of this material. The results of this study help to understand the range of pelletization, and operating pressures of all-solid-state lithium sulfur batteries made with Li6PS5Cl0.5Br0.5 crystalline electrolyte material.

In recent years, autonomous vehicles are at the forefront of the vehicle industry’s attention. Due to the fact that autonomous vehicles are driverless, the safety of these type of vehicles is more important to ensure the passengers safety. To improve the vehicle safety, intelligent tires can be used to provide tire and tire-pavement condition information to the autonomous vehicle control system. For this purpose, intelligent tires are equipped with different sensors such as temperature, pressure, wear and friction. These sensors need a sustainable and reliable power source so that the autonomous vehicle control system has access to the tire information at any conditions. Energy harvesters are proven to be applicable for tire waste strain energy harvesting to provide power for small on-board electronics. In this paper a strain-based energy harvester with the use of piezoelectric material is built and experimentally tested. A measurement system with wireless communication is also developed for online reading of the piezoelectric voltage and power. It is experimentally observed that the generated power by the piezoelectric energy harvester is enough to run the sensors tire. The effects of tire inflation pressure and normal load are also studied on the piezoelectric energy harvester (PEH) output voltage.

Lithium-ion batteries (LIBs) have driven the industry of rechargeable batteries in recent years due to their advantages such as high energy and power density and relatively long lifespan. Nevertheless, the dispose of spent LIBs has harmful impacts on the environment which needs to be addressed by recycling LIBs. However, none of the currently developed recycling processes is economical. The physical recycling process of LIBs may be economical if the cathode active materials can be separated, regenerated, and reused to make new LIBs. However, the first barrier for regeneration and reusing is the separation of different types of spent cathode active materials in the filter cake that are mixed with each other and come in the form of very fine powders with various sizes (< 30 μm) from the physical recycling process. The aim of this study is to separate the mixture of cathode active materials by adopting Stokes’ law. The focus will be only on mechanical separation with no thermal or chemical separation methods. For the validation, an experiment was designed and successfully performed where different types of spent cathode materials (e.g., LiCoO2, LiFePO4, and LiMn2O4) were separated from the spent anode materials (e.g., graphite) with high efficiency and reasonable time.

The quality of the collected data from a measurement system affects eventual decision making process. Therefore, the reliability of any measurement system is an important factor to be studied. Gauge repeatability and reproducibility (Gauge R&R) is the standard method to evaluate the measurement system and assess the adequacy of variation in the measurement data. Gauge R&R is a statistical tool which evaluates two main characteristics of the measurement system: repeatability and reproducibility. The Dynamic Mechanical Analysis (DMA) is a common measurement system for studying the dynamic mechanical properties of viscoelastic materials such as polymers. The newly developed High Frequency Dynamic Mechanical Analysis (HFDMA) is able to directly run the simple shear test at high frequencies without changing the specimen temperature. The complex shear modulus and damping factor of the viscoelastic materials are reported by the HFDMA system. In this study the uni-variable Gauge R&R study based on Analysis of Variance (ANOVA) is done on each measured characteristic of the HFDMA measurement system. The source of variations for each characteristic is distinguished. Then the multivariate Gauge R&R based on the Multivariate Analysis of Variance (MANOVA) is done and the percentage of multivariate Gauge R&R for the measurement with the multiple variables is reported. The results indicate that the HFDMA measurements are both repeatable and reproducible. Thus, the new HFDMA can be used as a measurement system to measure the mechanical properties of viscoelastic materials at high frequencies.

This paper presents the application of robotics for the disassembly of electric vehicle lithium-ion battery (LIB) packs for the purpose of recycling. Electric vehicle battery systems can be expensive and dangerous to disassemble, therefore making it cost inefficient to recycle them currently. Dangers associated with high voltage and thermal runaway make a robotic system suitable for this task, as the danger to technicians or workers is significantly reduced, and the cost to operate a robotic system would be potentially less expensive over the robots lifetime. The proposed method allows for the automated or semi-automated disassembly of electric vehicle LIB packs for the purpose of recycling. In order to understand the process, technicians were studied during the disassembly process, and the modes and operations were recorded. Various modes of interacting with the battery module were chosen and broken down into gripping and cutting operations. Operations involving cutting and gripping were chosen for experimentation, and custom end of arm tooling was designed for use in the disassembly process. Path planning was performed offline in both MATLAB/Simulink and ROBOGUIDE, and the simulation results were used to program the robot for experimental validation.

Drones or Unmanned Aerial Vehicles (UAV) are the aircraft controlled remotely by radio waves or autonomously and can fly without a pilot and passengers. Demands for drones with long flight times are increasing significantly in the personal and commercial applications. One of the main issues about drones is their power management. However, these devices are powered by a high energy density lithium battery, but a flight time range could be about 20–40 min. Increasing the battery energy storage capacity to achieve more flight time is not usually a good idea due to the additional weight in drones. In order to solve this issue, an Intelligent Battery Management System (IBMS) is proposed to predict the maximum available energy of the battery pack to make the best decision for finding the closest charging station depending on different weather conditions. In this study, lithium-ion battery with lithium titanite oxide (LTO) anode, as a fast charging and fast discharging battery, is used as the drone power supply. The proposed IBMS can not only increase the performance and life of the battery system but also it can estimate the battery cells state of charge (SOC) based on a system identification method. Results show that the proposed system has an accurate estimation of the maximum available energy, and therefore accurate flight time prediction to find the best recharging node for the drone.

In this study, the low-temperature energy efficiency of lithium-ion batteries (LIBs) with different chemistries and nominal capacities at various charge and discharge rates is studied through multi-physics modeling and computer simulation. The model is based on the irreversible heat generation in the battery, leading to the charge/discharge efficiency in LIBs with graphite/LiFePO4, graphite/LiMn2O4, and graphite/LiCoO2 electrode materials in which the effects of the battery nominal capacity at various charge and discharge rates are studied. Using characterized sources of the heat generation in the LIB leads to providing a battery efficiency plot at different operation condition for each LIBs. The results of this study assist the battery engineers to have much more accurate prediction over the efficiency of the LIBs at low temperatures.

A well-designed battery management system along with a set of voltage and current sensors is required to properly measure and control the battery cell operational variables for Hybrid Electric Aircrafts (HEAs). Some critical functions of the battery including State-Of-Charge (SOC) and State-Of-Health (SOH) estimations, over-current, and over-/under-voltage protections are mainly related to current and voltage sensor measurements. Therefore, in case of battery faults occur in HEA, designing a reliable and robust diagnostic procedure is essential. In this study, for Li-ion batteries, a new and fast fault diagnosis technique via collecting data is proposed. Finally, the effectiveness of the proposed diagnostic method is validated, and the results show how overcharge, over-discharge and sensor faults can be accurately detected.

At present, the lithium-ion battery (LIB) is the most important candidate for electrical energy storage for different applications, including electric and hybrid vehicles and aircraft. Although many studies have been done so far to evaluate performance and durability of LIB cells and packs for vehicle application, there is no study for the application of LIBs in electric and hybrid aircraft. In this paper, the cycle life and calendar life of a typical aftermarket LIB are studied through an empirical modeling method. The degradation rate of the battery for a typical light-weight passenger aircraft with a flight range of less than 1000 km is presented. The real duty-cycle of the battery for this aircraft is used for the cycle-life analysis.

In this work, the energy efficiency of the lithium-ion batteries (LIB) with graphite anode and LiFePO4 cathode (G/LFP) at different nominal capacities and charge/discharge rates is studied through multiphysics modeling and computer simulation. After characterizing all the heat generation sources in the cell, the total heat generation in LIBs is calculated and the charge/discharge efficiency plots at different temperatures are obtained. Since G/LFP LIBs have a wide range of applications in passenger and commercial electric vehicles (EVs), the result of this study assist engineer toward more efficient battery pack design.

Ambient energy harvesting using piezoelectric transducers is becoming popular to provide power for small microelectronics devices. The deflection of tires during rotation is an example of the source of energy for electric power generation. This generated power can be used to feed tire self-powering sensors for bicycles, cars, trucks, and airplanes. The aim of this study is to optimize the energy efficiency of a rainbow shape piezoelectric transducer mounted on the inner layer of a pneumatic tire for providing enough power for microelectronics devices required to monitor tires. For this aim a rainbow shape piezoelectric transducer is adjusted with the tire dimensions and excited based on the car speed and strain. The geometry and load resistance effects of the piezoelectric transducer is optimized using Multiphysics modeling and finite element analysis.