Rechargeable Lithium Polymer Research Articles

Radiation Testing of Commercial Rechargeable Lithium Polymer Batteries for Small Satellite Applications

Commercial off-the-shelf (COTS) electrical components are becoming of interest for small satellite applications due to their accessibility, good performance, and low cost. We quantify the performance of Lithium Polymer (LiPo) COTS batteries under irradiation to assess their reliability. LiPo battery cells with LiCoO2 cathodes, nominal voltages of 3.7 V, and rated capacities of 6000 mAh are irradiated with a 30 MeV proton beam from the Middle East Technical University Defocusing Beamline, which delivers a maximum of 73 krad primary dose. Results show protons cause short-term damage, resulting in up to 17% faster discharge rates, which decreases after six months depending on the cell’s position and primary and secondary deposited dose. Additionally, a consumption rate increase of up to 42% occurs for the cells under prolonged secondary irradiation (1.2 krad). The separating polypropylene layer undergoes thinning and discoloration mainly due to secondary particles like neutrons and gammas. Finally, the LiCoO2 cathode of two batteries show dried polyvinylidene fluoride surface build-up, both potentially caused by discharge in a radioactive environment. Damaged cells do not suffer leakage.

Design and Analysis of All-Terrain Differential-Driven Caterpillar-Wheeled Based Unmanned Fire Extinguisher Robot

The usage of wheeled robots in service robots such as planetary exploration robots, pick-and-place robots, cleaning robots, surveillance robots, etc., is continuously increasing day by day. The primary purpose of these service robots is to reduce human resources and minimize human life risk in a hazardous environment. Therefore, in this article, the authors purpose and design the all-terrain differential-driven caterpillar-wheeled based unmanned Fire Extinguisher Robot (FER), which can detect and monitor the fire by using gas (smoke) sensor and temperature sensor. Also, it can extinguish the fire by spreading the fire extinguisher gas. The proposed unmanned FER has been divided into the two assembled units, one unit drives the FER, and another unit is for spreading the fire extinguisher gas through the nozzle of the cylinder. The driving unit of unmanned FER consists of six DC geared motors, two dual DC motor drivers, caterpillar driving wheels, Arduino MEGA microcontroller, Bluetooth module, gas sensor, temperature sensor, and rechargeable lithium-polymer (LiPo) battery. Next, the one DC motor connected with a motor driver controls the fire extinguisher gas cylinder's open and close valve through a Bluetooth signal from an android phone. The specially designed chassis and caterpillar driving wheel arrangement help the FER to travel in any terrain, including stair climbing. Real-time experimental tests have been carried out on the designed unmanned FER during the fire extinguishing process to prove the effectiveness of the developed FER.

Evaluation of health and safety of mechanically fatigued rechargeable lithium polymer batteries for flexible electronics applications

The state-of-health (SOH) and safety of flexible batteries exposed to mechanical fatigue conditions are important issues for the durable and reliable operations of flexible and wearable electronics. In this research, the effects of fatigue deformation of a flexible lithium polymer battery on its capacity fade, SOH, and safety were investigated. Mechanical fatigues under bending, torsion, and complex strain modes at various strains accelerated the SOH degradation of the battery. The electrochemical impedance spectroscopy (EIS) spectra (i.e. Nyquist plots) were analyzed to understand the microdamage occurred to the battery material. The total electrochemical impedance value obtained using EIS tends to be inversely proportional to the SOH value of the fatigued battery. Lithium metal precipitation was observed on the disassembled graphite surface of the fatigued battery, whereas no such hazard existed on the as-received one. The needle-like precipitate resulted in local puncturing of the polymer separator in the fatigued battery.

Measurement of Core Body Temperature Using Graphene-Inked Infrared Thermopile Sensor.

Continuous and reliable measurements of core body temperature (CBT) are vital for studies on human thermoregulation. Because tympanic membrane directly reflects the temperature of the carotid artery, it is an accurate and non-invasive method to record CBT. However, commercial tympanic thermometers lack portability and continuous measurements. In this study, graphene inks were utilized to increase the accuracy of the temperature measurements from the ear by coating graphene platelets on the lens of an infrared thermopile sensor. The proposed ear-based device was designed by investigating ear canal geometry and developed with 3D printing technology using the Computer-Aided Design (CAD) Software, SolidWorks 2016. It employs an Arduino Pro Mini and a Bluetooth module. The proposed system runs with a 3.7 V, 850 mAh rechargeable lithium-polymer battery that allows long-term, continuous monitoring. Raw data are continuously and wirelessly plotted on a mobile phone app. The test was performed on 10 subjects under resting and exercising in a total period of 25 min. Achieved results were compared with the commercially available Braun Thermoscan, Original Thermopile, and Cosinuss One ear thermometers. It is also comprehended that such system will be useful in personalized medicine as wearable in-ear device with wireless connectivity.

Evaluation of the ventilation unit for personal cooling system (PCS)

BackgroundWorkers are vulnerable to heat stress when they perform tasks in hot environments. Personal cooling systems (PCSs) are designed to reduce heat strain. A cooling vest with ventilation fans is a type of PCS that can blow air around the body to facilitate convective and evaporative cooling. ObjectiveThis study aims to evaluate the performance of a ventilation unit for a tailor-made cooling vest designed to protect construction workers from heat stress. The performance of this newly designed ventilation unit (Unit B) was compared with that of the ventilation unit used in a commercially available cooling vest (Unit A). MethodThe designed ventilation unit consists of a pair of ventilation fans and a portable battery pack. A hot wire anemometer was used to measure the air flow rate of the fan. The air flow rate and work duration of different ventilation units were compared. The sweating manikin test was conducted to further compare the cooling powers of the ventilation units. ResultCompared with Unit A powered by the alkaline AA battery (6 V, 2122 mAh), Unit B powered by the rechargeable lithium-polymer (Li-Po) battery (7.4 V, 4400 mAh) achieved a higher air flow rate (8–22 L/s vs. 0–13 L/s) and longer work duration (7.05 h vs. 6.22 h). The average cooling power of Unit B on the sweating manikin was 68 W, which was higher than that of Unit A (51 W). Practical applicationsResults showed that the newly designed ventilation unit exhibited higher air flow rate and cooling power. The ventilation unit designed in this study will be incorporated into a tailor-made PCS for protecting workers in the heat.

압전 세라믹을 이용한 스마트 웨어용 진동-촉각 액추에이터

In this study, the vibration-based tactile actuator for smart wear applications is presented by using piezoelectric ceramic transducers. The compact wireless actuation system is constructed with a high voltage piezoelectric amplifier, a microcontroller, wireless communication module, and rechargeable lithium-polymer battery. For the wireless communication between a hardware and an operator, the bluetooth-based wireless communication system is prepared and the user interface is provided via smart phone applications. From a series of experimental user studies, it is demonstrated that the proposed vibro-tactile actuator based on piezoelectric ceramic transducers can be effectively applied to smart wear applications.

Evaluating batteries for advanced wildlife telemetry tags

The authors evaluate miniature batteries as potential power sources for advanced wildlife telemetry tags. These tags are often based on integrated ultrahigh frequency transceivers that are designed for wireless sensor networks and that consume 18–85 mA while receiving or transmitting. This current drain is challenging for many types of miniature batteries. The authors evaluate batteries both on actual tags and in a specialised synthetic-load circuit. The evaluation focuses on the total amount of energy that the battery delivers until the tag fails, but the authors also investigate other important issues, such as the ability to withstand immersion in water. The main findings are that zinc-air cells designed mainly for hearing aids perform extremely well in terms of effective energy density (but are hard to deploy), that lithium coin cells require a reservoir capacitor to deliver their rated energy (which is about half of that of zinc air with the same weight) and that rechargeable lithium polymer cells perform well even without a reservoir capacitor.

Hand-held portable desorption atmospheric pressure chemical ionization ion source for in situ analysis of nitroaromatic explosives.

A novel, lightweight (0.6 kg), solvent- and gas-cylinder-free, hand-held ion source based on desorption atmospheric pressure chemical ionization has been developed and deployed for the analysis of nitroaromatic explosives on surfaces in open air, offering portability for in-field analysis. A small, inexpensive, rechargeable lithium polymer battery was used to power the custom-designed circuitry within the device, which generates up to ±5 kV dc voltage to ignite a corona discharge plasma in air for up to 12 h of continuous operation, and allowing positive- and negative-ion mass spectrometry. The generated plasma is pneumatically transported to the surface to be interrogated by ambient air at a rate of 1-3.5 L/min, compressed using a small on-board diaphragm pump. The plasma source allows liquid or solid samples to be examined almost instantaneously without any sample preparation in the open environment. The advantages of low carrier gas and low power consumption (<6 W), as well as zero solvent usage, have aided in developing the field-ready, hand-held device for trigger-based, "near-real-time" sampling/ionization. Individual nitroaromatic explosives (such as 2,4,6-trinitrotoluene) can be easily detected in amounts as low as 5.8 pg with a linear dynamic range of at least 10 (10-100 pg), a relative standard deviation of ca. 7%, and an R(2) value of 0.9986. Direct detection of several nitroaromatic compounds in a complex mixture without prior sample preparation is demonstrated, and their identities are confirmed by tandem mass spectrometry fragmentation patterns.

Rechargeable Lithium Polymer Batteries Assembled with Electrospun Poly(ethylene oxide) Membranes

Solid polymer electrolytes have been paid much attention in rechargeable lithium batteries, due to absence of electrolyte leakage, enhanced safety and design flexibility [1,2]. Solid polymer electrolytes studied to date are mainly based on poly(ethylene oxide)(PEO) containing lithium salts. However, these materials have a major drawback that the ionic conductivity for practical application can only be reached at high temperature, due to the high degree of crystallinity inherent in these complexes at ambient temperature. Because of the inherent drawback, various attempts such as grafting, block copolymerization, interpenetration polymer network have been tried to incorporate PEO into a macromolecular sequence, which inhibits crystallization, while maintaining a low value of the glass transition temperature. In our study, with the aim of developing highly conductive polymer electrolytes with high mechanical strength, we prepared the cross-linked polymer electrolytes using low-molecular weight PEO, which are supported by electrospun nanoporous membrane based on high-molecular weight PEO. In this system, mechanically robust porous membrane with chemical cross-linking can protect against electric short to assure safety reliability and make a flexible thin film. By using these solid polymer electrolytes, the lithium polymer cells are assembled and their cycling performances are evaluated at room temperature.

Effects of mechanical deformation on electric performance of rechargeable batteries embedded in load carrying composite structures

Integrating rechargeable battery cells with fibre reinforced polymer matrix composites is a promising technology to enable composite structures to concurrently carry load and store electric energy, thus significantly reducing weight at the system level. To develop a design criterion for structural battery composites, rechargeable lithium polymer battery cells were embedded into carbon fibre/epoxy matrix composite laminates, which were then subjected to tensile, flexural and compressive loading. The electric charging/discharging properties were measured at varying levels of applied loads. The results showed that degradation in battery performance, such as voltage and energy storage capacity, correlated well with the applied strain under three different loading conditions. Under compressive loading, battery cells, due to their multilayer construction, were unable to prevent buckling of composite face sheets due to the low lateral stiffness, leading to lower compressive strength than sandwich panels with foam core.

Development of novel PMMA-based polyelectrolyte gels containing linear chains of LiAMPS copolymers

Charge transport and mechanical properties are coupled with each other in a semi-interpenetrating network gel, in which the ionic polymer chains are intertwined with but not covalently bonded to a network by the cross linked non-ionic polymer poly (methyl methacrylate) (PMMA). In this study, an attempt has been made to synthesize new semi-interpenetrating polymer gel electrolytes with high conductivity as well as strength for use in rechargeable lithium polymer batteries. The gels are synthesized from methyl methacrylate and the copolymers of lithium salt of 2-acrylamido-2-methylpropanesulfonic acid (LiAMPS) with four different monomers; styrene, vinyl acetate, Veova 10 and sodium styrene sulphonate. The gels are made by first synthesizing linear chains of LiAMPS-co-monomers copolymers by free radical polymerization of LiAMPS and each monomer dissolved in dimethylacetamide (DMA), then polymerization of methyl methacrylate and a cross linking monomer (tetraethyleneglycol diacrylate) to form the semi-interpenetrating network. The electrical conductivity of each gel is determined as a function of monomer/LiAMPS ratio. Compared to Poly (LiAMPS) and other copolymers, the gels based on LiAMPS-co-styrene copolymers show a good balance between conductivity and strength properties.

Optimization of un-tethered, low voltage, 20–100 kHz flexural transducers for biomedical ultrasonics applications

This paper describes optimization of un-tethered, low voltage, 20–100kHz flexural transducers for biomedical ultrasonics applications. The goal of this work was to design a fully wearable, low weight (<100g), battery operated, piezoelectric ultrasound applicator providing maximum output pressure amplitude at the minimum excitation voltage.Such implementation of ultrasound applicators that can operate at the excitation voltages on the order of only 10–25V is needed in view of the emerging evidence that spatial-peak temporal-peak ultrasound intensity (ISPTP) on the order of 100mW/cm2 delivered at frequencies below 100kHz can have beneficial therapeutic effects. The beneficial therapeutic applications include wound management of chronic ulcers and non-invasive transdermal delivery of insulin and liposome encapsulated drugs.The early prototypes of the 20 and 100kHz applicators were optimized using the maximum electrical power transfer theorem, which required a punctilious analysis of the complex impedance of the piezoelectric disks mounted in appropriately shaped metal housings.In the implementation tested, the optimized ultrasound transducer applicators were driven by portable, customized electronics, which controlled the excitation voltage amplitude and facilitated operation in continuous wave (CW) or pulsed mode with adjustable (10–90%) duty cycle. The driver unit was powered by remotely located rechargeable lithium (Li) polymer batteries. This was done to further minimize the weight of the applicator unit making it wearable. With DC voltage of approximately 15V the prototypes were capable of delivering pressure amplitudes of about 55kPa or 100mW/cm2 (ISPTP). This level of acoustic output was chosen as it is considered safe and side effects free, even at prolonged exposure.

Grafting of LiAMPS on ethyl cellulose: a route to the fabrication of superior quality polyelectrolyte gels for rechargeable Lithium ion batteries

New types of semi-interpenetrating polymer gel electrolytes with high conductivity as well as strength for use in rechargeable Lithium polymer batteries are synthesized. Single ion conducting polyelectrolyte gels are made by first synthesizing grafted linear chains of Lithium salt of 2-acrylamido-2-methylpropane sulphonic acid on ethyl cellulose (EC) using free radical initiator azobis (cyclohexanecarbonitrile) in dimethyl acetamide solvent, then copolymerizing methyl methacrylate (MMA) and a crosslinking agent ethyleneglycol dimethacrylate to form semi-interpenetrating network. The effect of concentrations of EC and MMA on electrical conductivity and mechanical strength of gels are determined.

Design and simulation of advanced charge recovery piezoactuator drivers

The German Artificial Sphincter System project aims at the development of an implantable sphincter prosthesis driven by a piezoelectrically actuated micropump. The system has been designed to be fully implantable, i.e. the power supply is provided by a rechargeable lithium polymer battery. In order to provide sufficient battery duration and to limit battery dimensions, special effort has to be made to minimize power consumption of the whole system and, in particular, of the piezoactuator driver circuitry. Inductive charge recovery can be used to recover part of the charge stored within the actuator. We are going to present a simplified inductor-based circuit capable of voltage inversion across the actuator without the need of an additional negative voltage source. The dimension of the inductors required for such a concept is nevertheless significant. We therefore present a novel alternative concept, called direct switching, where the equivalent capacitance of the actuator is charged directly by a step-up converter and discharged by a step-down converter. We achieved superior performance compared to a simple inductor-based driver with the advantage of using small-size chip inductors. As a term of comparison, the performance of the aforementioned drivers is compared to a conventional driver that does not implement any charge recovery technique. With our design we have been able to achieve more than 50% reduction in power consumption compared to the simplest conventional driver. The new direct switching driver performs 15% better than an inductor-based driver. A novel, whole-system SPICE simulation is presented, where both the driving circuit and the piezoactuator are modeled making use of advanced nonlinear models. Such a simulation is a precious tool to design and optimize piezoactuator drivers.

High performance PEO-based polymer electrolytes and their application in rechargeable lithium polymer batteries

Solvent-free, lithium-ion-conducting, composite polymer electrolytes have been prepared by a double dispersion of an anion trapping compound, i.e., calyx(6)pyrrole, CP and a ceramic filler, i.e., super acid zirconia, S-ZrO2 in a poly(ethylene oxide)-lithium bis(oxalate) borate, PEO–LiBOB matrix. The characterization, based on differential thermal analysis and electrochemical analysis, showed that while the addition of the S-ZrO2 has scarce influence on the transport properties of the composite electrolyte, the unique combination of the anion-trapping compound, CP, with the large anion lithium salt, LiBOB, greatly enhances the value of the lithium transference number without depressing the overall ionic conductivity. These unique properties make polymer electrolytes, such as PEO20LiBOB(CP)0.125, of practical interest, as in fact confirmed by tests carried out on lithium battery prototypes.

Polyaniline/Carbon Nanotube Composite Cathode for Rechargeable Lithium Polymer Batteries Assembled with Gel Polymer Electrolyte

A nanocomposite of polyaniline (PANI) and multiwalled carbon nanotube (CNT) was prepared by the in situ chemical polymerization of aniline in well-dispersed CNT solution. The PANI/CNT composite was employed as an active cathode material in rechargeable lithium polymer cells. Gel polymer electrolyte based on the porous poly(vinylidenefluoride-co-hexafluoropropylene) membrane was used as an electrolyte material in assembling the cells. The cell delivered a maximum discharge capacity of at the 80th cycle with an average coulombic efficiency of 98%. To investigate the effect and role of CNT in the above composite, two different kinds of cathodes were prepared by mechanically mixing the pure polyaniline with CNT or super-p carbon separately. The electrochemical performances of these two cathode materials were also evaluated in the lithium polymer cells.

Plenary Address- New Types of Rechargeable Lithium and Lithium-Ion Polymer Batteries

The activities in progress in our laboratory for the development of new types of lithium batteries to be proposed for portable electronics and hybrid car application, are reviewed and discussed. The research has been mainly focused on the characterization of new electrode and electrolyte materials. Results related to improved, solvent-free , as well as gel-type, polymer electrolytes are particularly stressed. It is shown that the use of proper gel electrolytes in combination with suitable electrode couples, allows the development of new types of safe, reliable and low cost lithium ion batteries which appear very promising power sources for hybrid vehicles.

Nanostructured Polyaniline and its Composite as Cathode Materials in Rechargeable Lithium Polymer Cells Assembled with Gel Polymer Electrolyte

not Available.

Plenary Address- New Types of Rechargeable Lithium and Lithium-ion Polymer Batteries

not Available.

Room-Temperature Mechanosynthesis of Ni3S2 as Cathode Material for Rechargeable Lithium Polymer Batteries

The formation of was realized by mechanical alloying with metallic nickel and sulfur powder as precursors. The products were characterized by X-ray diffraction, thermoanalysis, and scanning electron microscopy. Electrochemical properties of cells were also presented. The initial discharge capacity of was , with a platform at about vs . A capacity fading rate of 0.5% per cycle was achieved within . The charge–discharge mechanism of was implied by the analysis of the charge–discharge potential profiles, the cyclic voltammetry traces, and the ex situ XRD patterns of the cathode.