Batteries — Open Access Journal

Primary battery recycling has important environmental and economic benefits. According to battery sales worldwide, the most used battery type is alkaline batteries with 75% of market share due to having a higher performance than other primary batteries such as Zn–MnO₂. In this study, carbothermal reduction for zinc oxide from battery waste was completed for both vacuum and Ar atmospheres. Thermodynamic data are evaluated for vacuum and Ar atmosphere reduction reactions and results for Zn reduction/evaporation are compared via the FactSage program. Zn vapor and manganese oxide were obtained as products. Zn vapor was re-oxidized in end products; manganese monoxide and steel container of batteries are evaluated as ferromanganese raw material. Effects of carbon source, vacuum, temperature and time were studied. The results show a recovery of 95.1% Zn by implementing a product at 1150 °C for 1 h without using the vacuum. The residues were characterized by Atomic Absorption Spectrometer (AAS) and X-ray Diffraction (XRD) methods. Full article

To ensure sufficient thermal performance within electric vehicle (EV) batteries, thermal interface materials (TIMs), such as pastes or adhesives, are widely used to fill thermally insulating voids between cells and cooling components. However, TIMs are composite materials that are subject to degradation over the battery’s lifetime. Using TIMs for battery applications is a new and emerging topic, creating the need to rapidly acquire knowledge about appropriate lifetime testing and evaluation methods, in close collaboration with the battery manufacturers. This paper reviews suitable methods for durability testing as well as basic modeling approaches which allow for the transfer of laboratory results to the longtime behavior of interface materials during a vehicle’s lifetime. Full article

This paper focuses on the fast characterization of automotive second life lithium-ion batteries that have been recently re-used in many projects to create battery storages for stationary applications and sporadically for embedded applications. Specific criteria dedicated to the second life are first discussed. After a short review of the available state of health indicators and their associated determination techniques, some electrical characterization tests are explored through an experimental campaign. This offline identification aims to estimate the remaining ability of the battery to store energy. Twenty-four modules from six different commercial electric vehicles are analyzed. Well-known methodologies like incremental capacity analysis (ICA) and constant voltage phase analysis during CC-CV charge highlight the difficulty—and sometimes the impossibility—to apply traditional tools on a battery pack or on individual modules, in the context of real second life applications. Indeed, the diversity of the available second life batteries induces a combination of aging mechanisms that leads to a complete heterogeneity from a cell to another. Moreover, due to the unknown first life of the battery, typical state of health determination methodologies are difficult to use. A new generic technique based on a partial coulometric counter is proposed and compared to other techniques. In the present case study, the partial coulometric counter allows a fast determination of the capacity aging. In conclusion, future improvements and working tracks are addressed. Full article

Corrosion and discharge behavior of battery-grade zinc particles coated with a silica layer doped with bismuth was investigated and compared with untreated zinc powder. Electrochemical investigations were carried out in half-cell configuration. The electrolyte was 6 M KOH in excess. Coated zinc particles provided a discharge capacity of 737 mAh g⁻¹ (89.9% DoD) versus 633 mAh g⁻¹ (77.2% DoD) of untreated zinc particles after a dwell time of 1 h in KOH. The silica coating reduced the direct contact of the zinc surface with the electrolyte and thus minimized the hydrogen evolution reaction, which led to an increased discharge capacity. Additionally, bismuth doping enhanced conductivity within the silica coating and increased zinc utilization. Those coated zinc particles inhibited corrosion, i.e., corrosion efficiency reached 87.9% compared to uncoated zinc. Additionally, the coating achieved a capacity retention of 90.9% (670 mAh g⁻¹) after 48 h dwell time in 6 M KOH. The coatings were prepared by sol-gel technology and characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) surface determination. Full article

A precise lithium-ion battery model is required to specify their appropriateness for different applications and to study their dynamic behavior. In addition, it is important to design an efficient battery system for power applications. In this investigation, a second-order equivalent electrical circuit battery model, which is the most conventional method of characterizing the behavior of a lithium-ion battery, was developed. The current pulse procedure was employed for parameterization of the model. The construction of the model was described in detail, and a battery model for a 13 Ah lithium titanate oxide battery cell was demonstrated. Comprehensive characterization experiments were accomplished for an extensive range of operating situations. The outcomes were employed to parameterize the suggested dynamic model of the lithium titanate oxide battery cell. The simulation outcomes were compared to the laboratory measurements. In addition, the proposed lithium-ion battery model was validated. The recommended model was assessed, and the proposed model was able to anticipate precisely the current and voltage performance. Full article

In this scientific publication, a new sensor approach for status monitoring, such as state of charge and state of health, of lithium ion batteries by using special Bragg gratings inscribed into standard optical glass fibers is presented. In addition to well-known core gratings, embedded into the anode of 5 Ah lithium ion pouch cells as a strain monitoring unit, the manufacturing of a surface cladding waveguide Bragg grating sensor incorporated into the cell’s separator, that is sensitive to changes of the refractive index of the surrounding medium, is demonstrated. On the basis of the experiments carried out, characteristics of the cell behavior during standard cyclization and recognizable marks in subsequent post-mortem analyses of the cell components are shown. No negative influence on the cell performance due to the integrated sensors have been observed; however, the results show a clear correlation between fading cell capacity and changes of the interior optical signals. Additionally, with the novel photonic sensor, variations in the electrolyte characteristics are determinable as the refractive index of the solution changes at different molar compositions. Furthermore, with the manufactured battery cells, abuse tests by overcharging were conducted, and it was thereby demonstrated how internal battery sensors can derive additional information beyond conventional battery management systems to feasibly prevent catastrophic cell failures. The result of the research work is an early stage photonic sensor that combines chemical, mechanical and thermal information from inside the cell for an enhanced battery status analysis. Full article

Devices operating in complete energy autonomy are multiplying: small fixed signaling applications or sensors often operating in a network. To ensure operation for a substantial period, for applications with difficult physical access, a means of storing electrical energy must be included in the system. The battery remains the most deployed solution. Lead-acid batteries still have a significant share of this market due to the maturity of their technology. However, even by sizing all the system elements according to the needs and the available renewable energy, some failure occurs. The battery is the weak element. It can be quickly discharged when the renewable energy source is no longer present for a while. It can also be overloaded or subjected to high temperatures, which affects its longevity. This paper presents a suggested improvement for these systems, systematically adding extra devices to reduce excess charges and heat and allowing the battery use at lower charges. The interest of this strategy is presented by comparing the number of days of system failure and the consequences for battery aging. To demonstrate the interest of the proposed improvement track, a colored Petri net is deployed to model the battery degradation parameters evolution, in order to compare them. Full article

Lithium-ion Capacitors (LiCs) that have intermediate properties between lithium-ion batteries and supercapacitors are still considered as a new technology whose aging is not well studied in the literature. This paper presents the results of accelerated aging tests applied on 12 samples of LiCs. Two high temperatures (60 °C and 70 °C) and two voltage values were used for aging acceleration for 20 months. The maximum and the minimum voltages (3.8 V and 2.2 V respectively) had different effects on capacitance fade. Cells aging at 2.2 V encountered extreme decrease of the capacitance. After storing them for only one month at 60 °C, they lost around 22% of their initial capacitance. For this reason, an aging model was developed for cells aging at the lowest voltage value to emphasize the huge decrease of the lifetime at this voltage condition. Moreover, two measurement tools of the capacitance were compared to find the optimal method for following the evolution of the aging process. It was proved that electrochemical impedance spectroscopy is the most accurate measurement technique that can reveal the actual level of degradation inside a LiC cell. Full article

The pores in silicon particles can accommodate the volume expansion of silicon during the charging–discharging process. However, pores in silicon particles are easily occupied by carbon during the preparation of silicon/carbon composites. In this paper, sulfur was adsorbed in the pores of porous silicon particles before polyaniline (PANI) coating by in-situ polymerization, so that the pores were preserved in porous [email protected] (p-Si/@C) composites after the sublimation of sulfur during carbonization. The microstructure and the electrochemical performances of the obtained p-Si/@C composites were investigated. The results indicate that p-Si/@C composites prepared with a sulfur-melting process show a better high-rate performance than those without a sulfur-melting process. Remarkably, the former show a better capacity retention when returning to a low current density. The reversible capacities of the former were 1178 mAh·g⁻¹, 1055 mAh·g⁻¹, 944 mAh·g⁻¹, and 751 mAh·g⁻¹ at 0.2 A·g⁻¹, 0.3 A·g⁻¹, 0.5 A·g⁻¹, and 1.0 A·g⁻¹, respectively. Moreover, the reversible capacities could return to 870 mAh·g⁻¹, 996 mAh·g⁻¹, and 1027 mAh·g⁻¹ when current densities returned to 0.5, 0.3, and 0.2 A·g⁻¹, respectively. Full article

Mechanical and electrochemical stability are key issues for large-scale production of solid state Li-ion batteries. Polymer electrolytes can provide good ionic conductivity, but mechanical strength needs to be improved. In this study, we investigate the correlation of mechanical and electrical properties of poly (ethylene oxide) (PEO)-based solid electrolytes for Li-ion batteries. The influence of alumina and LiClO₄ addition are investigated. Differential scanning calorimetry (DSC) is used to study the thermal behavior of salt-free and salt-containing samples and to identify the melting temperature. Dynamic mechanical analysis reveals the elastic properties as a function of temperature. Electrochemical properties are investigated using impedance spectroscopy. It is found that addition of alumina increases mechanical strength, while LiClO₄ decreases it. Addition of LiClO₄ and Al₂O₃ increases ionic conductivity and improves mechanical properties. However, there is no overlapping window of high mechanical strength and high ionic conductivity. Full article

Current redox flow battery (RFB) stack models are not particularly conducive to accurate yet high-throughput studies of stack operation and design. To facilitate system-level analysis, we have developed a one-dimensional RFB stack model through the combination of a one-dimensional Newman-type cell model and a resistor-network to evaluate contributions from shunt currents within the stack. Inclusion of hydraulic losses and membrane crossover enables constrained optimization of system performance and allows users to make recommendations for operating flow rate, current densities, and cell design given a subset of electrolyte and electrode properties. Over the range of experimental conditions explored, shunt current losses remain small, but mass-transfer losses quickly become prohibitive at high current densities. Attempting to offset mass-transfer losses with high flow rates reduces system efficiency due to the increase in pressure drop through the porous electrode. The development of this stack model application, along with the availability of the source MATLAB code, allows for facile approximation of the upper limits of performance with limited empiricism. This work primarily presents a readily adaptable tool to enable researchers to perform either front-end performance estimates based on fundamental material properties or to benchmark their experimental results. Full article

A vanadium oxygen fuel cell is a modified form of a conventional vanadium redox flow battery (VRFB) where the positive electrolyte (VO²⁺/VO₂⁺ couple) is replaced by the oxygen reduction (ORR) process. This potentially allows for a significant improvement in energy density and has the added benefit of overcoming the solubility limits of V (V) at elevated temperatures, while also allowing the vanadium negative electrolyte concentration to increase above 3 M. In this paper, a vanadium oxygen fuel cell with vanadium electrolytes with a concentration of up to 3.6 M is reported with preliminary results presented for different electrodes over a range of current densities. Using precipitation inhibitors, the concentration of vanadium can be increased considerably above the commonly used 2 M limit, leading to improved energy density. Full article

Lithium-ion battery packs inside electric vehicles represents a high share of the final price. Nevertheless, with technology advances and the growth of the market, the price of the battery is getting more competitive. The greenhouse gas emissions and the battery cost have been studied previously, but coherent boundaries between environmental and economic assessments are needed to assess the eco-efficiency of batteries. In this research, a detailed study is presented, providing an environmental and economic assessment of the manufacturing of one specific lithium-ion battery chemistry. The relevance of parameters is pointed out, including the manufacturing place, the production volume, the commodity prices, and the energy density. The inventory is obtained by dismantling commercial cells. The correlation between the battery cost and the commodity price is much lower than the correlation between the battery cost and the production volume. The developed life cycle assessment concludes that the electricity mix that is used to power the battery factory is a key parameter for the impact of the battery manufacturing on climate change. To improve the battery manufacturing eco-efficiency, a high production capacity and an electricity mix with low carbon intensity are suggested. Optimizing the process by reducing the electricity consumption during the manufacturing is also suggested, and combined with higher pack energy density, the impact on climate change of the pack manufacturing is as low as 39.5 kg CO₂ eq/kWh. Full article

Batteries have been extensively used in many applications; however, very little is explored regarding the possible environmental impacts for their whole life cycle, even though a lot of studies have been carried out for augmenting performance in many ways. This research paper addresses the environmental effects of two different types of batteries, lithium-ion (LiIo) and nickel-metal hydride (NiMH) batteries, in terms of their chemical constituents. Life cycle impact analysis has been carried out by the CML, ReCiPe, EcoPoints 97, IPCC, and CED methods. The impacts are considered in categories such as global warming, eutrophication, freshwater aquatic ecotoxicity, human toxicity, marine aquatic ecotoxicity and terrestrial ecotoxicity. The results reveal that there is a significant environmental impact caused by nickel-metal hydride batteries in comparison with lithium-ion batteries. The reason behind these impacts is the relatively large amount of toxic chemical elements which are present as constituents of NiMH batteries. It can be anticipated that a better environmental performance can be achieved through optimization, especially by cautiously picking the constituents, taking into account the toxicity aspects, and by minimizing the impacts related to these chemicals. Full article

In this work, we use ultrasonication and chemical etching agents to assist preparation of metal current collectors with nano-scale pores on the surface. Four different current collectors (copper foil, copper foam, aluminum foil, and aluminum foam) are prepared. The preparation parameters, ultrasonic time and etching agent concentration, are investigated and optimized accordingly. The morphologies of the as-prepared current collectors are observed under a scanning electronic microscope. Soft-packed lithium ion batteries with various current collectors are fabricated and tested. The prepared lithium ion batteries show good long-term cycle stability. The nanoporous structure of the current collector has little impact on the improvement of battery capacity under slow charging/discharging rates but has a positive impact on capacity retention under fast charging/discharging rates. Full article

The battery energy storage system has become an indispensable part of the current electricity network due to the vast integration of renewable energy sources (RESs). This paper proposes an optimal charging method of a vanadium redox flow battery (VRB)-based energy storage system, which ensures the maximum harvesting of the free energy from RESs by maintaining safe operations of the battery. The VRB has a deep discharging capability, long cycle life, and high energy efficiency with no issues of cell-balancing, which make it suitable for large-scale energy storage systems. The proposed approach determines the appropriate charging current and the optimal electrolyte flow rate based on the available time-varying input power. Moreover, the charging current is bounded by the limiting current, which prevents the gassing side-reactions and protects the VRB from overcharging. The proposed optimal charging method is investigated by simulation studies using MATLAB/Simulink. Full article

Lithium-ion batteries are the most commonly used source of power for modern electronic devices. However, their safety became a topic of concern after reports of the devices catching fire due to battery failure. Making safer batteries is of utmost importance, and several researchers are trying to modify various aspects in the battery to make it safer without affecting the performance of the battery. Electrolytes are one of the most important parts of the battery since they are responsible for the conduction of ions between the electrodes. In this paper, we discuss the different non-flammable electrolytes that were developed recently for safer lithium-ion battery applications. Full article

The increasing need for high capacity batteries in plug-in hybrids and all-electric vehicles gives rise to the question of whether these batteries should be equipped with a few large capacity cells or rather many low capacity cells in parallel. This article demonstrates the possible benefits of smaller cells connected in parallel because of discharge effects. Measurements have been conducted proving the beneficial influence of a lower SoC on the thermal runaway behaviour of lithium-ion cells. A second test series examines the short circuit currents during an ongoing thermal propagation in parallel-connected cells. With the help of a developed equivalent circuit model and the results of the test series two major system parameters, the ohmic resistance of a cell during thermal runaway $R_{\mathrm{tr}}$ and the resistance post thermal runaway $R_{\mathrm{ptr}}$ are extracted for the test set-up. A further developed equivalent circuit model and its analytical description are presented and illustrate the great impact of $R_{\mathrm{ptr}}$ on the overall discharged capacity. According to the model, cells with a capacity of no more than $C_{\mathrm{cell}}$ = 10–15 Ah and a parallel-connection of 24 cells show the most potential to discharge a significant amount. Full article

The currently preferred manufacturing method for Lithium-ion battery (LIB) electrodes is via the slurry route. While such an approach is appealing, the complexity of the electrode layers containing the active materials, conductivity helpers, and binders, has hampered detailed investigations of the active materials. As an alternative, an active material can be deposited as a thin film on a planar substrate, which enables a more robust and detailed analysis. However, due to the small areal capacity of nanometric thin films, the electrochemical activity of the cell casing must be negligible or at least well determined. We reported on the capacity and the differential capacity metrics of several materials used in the construction of the electrical terminals in LIBs. Among these materials, Ti was revealed to have the minimum reversible capacity for lithium-ion storage. The mechanical and electrochemical properties of the Ti–based materials were further improved through surface nitridation with thermal treatment in an ammonia-rich atmosphere. The nitridated Ti electrical terminal achieved a reversible capacity that was at least fifteen times lower than that of stainless steel, with a featureless differential capacity representation creating quasi-ideal experimental conditions for a detailed investigation of electroactive thin films. Full article