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Despite the structural and electrochemical advantages of LiFePO4 (LFP) as a cathode material, the solid-state reaction commonly used as a method to produce it at the industrial level has known disadvantages associated with high energy and fossil fuel consumption. On the other hand, solution-based synthesis methods present a more efficient way to produce LFP and have advantages such as controlled crystal growth, homogeneous morphology, and better control of pollutant emissions because the reaction occurs within a closed system. From an environmental point of view, different impacts associated with each synthesis method have not been studied extensively. The use of less polluting precursors during synthesis, as well as efficient use of energy and water, can provide new insights into the advantages of each cathode material for more environmentally friendly batteries. In this work, a solvothermal method is compared to a solid-state synthesis method commonly used to elaborate LFPs at the commercial level in order to evaluate differences in the environmental impacts of both processes. The solvothermal method used was developed considering the reutilization of solvent, water reflux, and a low thermal treatment to reduce pollutant emissions. As a result, a single high crystallinity olivine phase LFP was successfully synthesized. The use of ethylene glycol (EG) as a reaction medium enabled the formation of crystalline LFP at a low temperature (600 °C) with a nano-plate-like shape. The developed synthesis method was evaluated using life cycle analysis (LCA) to compare its environmental impact against the conventional production method. LCA demonstrated that the alternative green synthesis process represents 60% and 45% of the Resource Depletion impact category (water and fossil fuels, respectively) of the conventional method. At the same time, in the Climate change and Particular matter impact categories, the values correspond to 49 and 38% of the conventional method, respectively. [ABSTRACT FROM AUTHOR]

Summary: The battery thermal management system based on phase change materials (PCMs) has proven to be a safe, inexpensive, and high‐performance technology, which is currently gaining popularity over the other battery thermal management systems. PCMs are able to absorb heat generated by batteries, prolong battery life, and improve their performance. Organic compounds, such as paraffin, are widely used as phase change materials for the battery thermal management systems; however, there are no published data on the application of inorganic PCMs. Therefore, the main objective of this work is developing of two composite inorganic PCMs based on magnesium chloride hexahydrate and characterizing their properties for passive thermal control of lithium‐ion battery packs. Moreover, to have a valid baseline and compare the behavior of two inorganic PCMs with currently commercialized and well investigated organic PCM, paraffin wax was used as reference material for both mixtures. All three PCMs were impregnated into the expanded graphite matrix to enhance their thermal conductivity. The material characterization studies, including thermal properties investigation, density and viscosity measurements, soaking and compression testing, evaluation of thermal expansion, thermal conductivity, and micro X‐ray fluorescence analysis, were conducted for all PCMs. The results indicate that both inorganic mixtures are appropriate for thermal management of Li‐ion battery packs. Future work with the developed and characterized composite inorganic PCMs will include electrical cycling studies and nail penetration tests to reveal their effectiveness for passive thermal management of Li‐ion battery packs. [ABSTRACT FROM AUTHOR]

Microbial life inhabiting hypersaline environments belong to a limited group of extremophile or extremotolerant taxa. Natural or artificial hypersaline environments are not limited to high concentrations of NaCl, and under such conditions, specific adaptation mechanisms are necessary to permit microbial survival and growth. Argentina, Bolivia, and Chile include three large salars (salt flats) which globally, represent the largest lithium reserves, and are commonly referred to as the Lithium Triangle Zone. To date, a large amount of information has been generated regarding chemical, geological, meteorological and economical perspectives of these salars. However, there is a remarkable lack of information regarding the biology of these unique environments. Here, we report the presence of two bacterial strains (isolates LIBR002 and LIBR003) from one of the most hypersaline lithium-dominated man-made environments (total salinity 556 g/L; 11.7 M LiCl) reported to date. Both isolates were classified to the Bacillus genera, but displayed differences in 16S rRNA gene and fatty acid profiles. Our results also revealed that the isolates are lithium-tolerant and that they are phylogenetically differentiated from those Bacillus associated with high NaCl concentration environments, and form a new clade from the Lithium Triangle Zone. To determine osmoadaptation strategies in these microorganisms, both isolates were characterized using morphological, metabolic and physiological attributes. We suggest that our characterization of bacterial isolates from a highly lithium-enriched environment has revealed that even at such extreme salinities with high concentrations of chaotropic solutes, scope for microbial life exists. These conditions have previously been considered to limit the development of life, and our work extends the window of life beyond high concentrations of MgCl2, as previously reported, to LiCl. Our results can be used to further the understanding of salt tolerance, most especially for LiCl-dominated brines, and likely have value as models for the understanding of putative extra-terrestrial (e.g., Martian) life. [ABSTRACT FROM AUTHOR]

Salar de Atacama is one of the largest global reservoirs of natural lithium brines (mean lithium concentration = 1,500 ppm), enabling Chile to be a leading producer of lithium products. This large salar (3,000 km2), located in the Atacama Desert at 2,300 m above sea level, is dominated by microorganisms; however, little is known about the microbes present in the brines associated with this economically important mining process. Here we study lithium as a modulator of microbial richness and diversity in brines representing natural conditions (34.7% salinity) and conditions prior to lithium production with a concentrated brine (55.6% salinity). Brines only supported a single archaeal family (Halobacteriaceae): natural brines included the archaeal genera Halovenus, Natronomonas, Haloarcula, and Halobacterium. Concentrated brines included the archaeal genera Halovenus, Halobacterium, and Halococcus. The most abundant bacterial families in natural brine were Rhodothermaceae and Staphylococcaceae; Xanthomonadaceae dominated the bacterial community in the concentrated brine. A comparison of entire microbial community (Archaea and Bacteria) revealed that only seven operational taxonomic units were shared between samples, all of which were Archaea. Further, our results showed that Bacteria were phylogenetically more diverse and rich in the concentrated brine, while archaeal diversity was maximized in the natural brine. The concentrated lithium brines of the Salar de Atacama represent one of the most saline environments described to date (dominated by LiCl). We suggest that elevated concentrations of lithium could greatly modulate microbial diversity and give insights into the adaptive biology of microorganisms required to cope with extremely high concentrations of salts that extend beyond that of NaCl, a far more commonly studied salt. Plain Language Summary: Lithium is a main component of many of the batteries that we rely on for our daily use. In the last years, nearly 40% of all lithium obtained globally was from a single fragile salt‐lake ecosystem: Salar de Atacama in the Atacama Desert of northern Chile. This salar has extremely saline waters called brines (dominated by NaCl, aka table salt), which are naturally highly concentrated in lithium and concentrated in evaporation ponds. In total, concentrated brines has a salinity of 55.6% (ocean salinity = 0.3%), representing one of the most saline environments described on Earth to date (dominated by lithium chloride). Our research has shown that concentrated brines support life and are dominated by hundreds of species of microorganisms. Due to saline stress these "extremophiles" have developed very special (and previously undescribed) strategies to survive in this lithium soup. These results have implications beyond Earth: they have marked implications for our understanding for the potential for life on Mars, where liquid water is known to occur as brine. Although lithium production has clear economic importance, our results show that we should consider how we will preserve these unusual ecosystems that act as reservoirs of unique microbial life. Key Points: The microbial diversity of brines from Salar de Atacama differs according to the concentration of lithiumThe brines with low lithium concentrations were dominated by Archaea, and Bacteria dominated lithium‐ concentrated brinesOur research revealed the presence of microbial life in one of the most saline environments that has been described on Earth [ABSTRACT FROM AUTHOR]

Summary: Lithium salts are very important in the production of lithium batteries since they are used as precursors for the fabrication of cathode materials that require very low level of impurities (battery grade). Usually, the lithium extraction process from brine first yields lithium carbonate, which is then used as raw material for the production of other lithium compounds. However, it implies an increase in investment costs, considering more equipment and process stages. To remove the impurities and produce battery‐grade lithium compounds directly from brines, a laboratory‐scale process was developed using the methods of ion exchange and chemical precipitation. Thus, impurity‐free brine ready to be used in an industrial membrane electrolysis process is obtained. Different sequences and operating conditions were investigated for the purification of lithium‐concentrated brines, removing the main impurities of the natural brines: calcium, magnesium, and sulfate. For the characterization of solutions, crystals, and ion‐exchange resins, atomic absorption spectrophotometry, scanning electron microscopy, and X‐ray scattering spectroscopy were used. The results indicate that during the chemical precipitation process, lithium‐concentrated brine reacted with some additives (precipitating agents) at different stages in the batch reactors. Subsequently, the pulp obtained was sedimented and filtered, eliminating or reducing the impurities of the lithium brine. Thus, the most efficient precipitation sequence was evaluated as a function of the removal percentage of the species. The removal efficiencies obtained for Ca+2, Mg+2, and SO4−2 were of 98.93%, 99.93%, and 97.14%, respectively. Thereafter, the use of the ion‐exchange resins reduced the concentration of Ca+2 and Mg+2 to the values below 1 ppm. The combined use of both processes provided promising results that could be applied in the industry. [ABSTRACT FROM AUTHOR]

In this study, an inorganic mixture based on bischofite (industrial by-product) was developed and characterized for its application as a phase change material for low-temperature thermal energy storage. The most appropriate composition was established as 40 wt% bischofite and 60 wt% Mg(NO3)2 · 6H2O. Thermophysical properties were defined and compared with those of the mixture with synthetic MgCl2 · 6H2O. The heat of fusion and melting temperature were measured as 62.0°C and 132.5 kJ kg−1 for the mixture with MgCl2 · 6H2O and 58.2°C and 116.9 kJ kg−1 for the mixture with bischofite. The specific heat capacity values, cycling, and thermal stability for both mixtures were also determined. For the mixture with MgCl2 · 6H2O, the densities of the solid and liquid states were 1517 kg m−3 (ambient temperature) and 1515 kg m−3 (at 60-70°C), respectively. For the mixture with bischofite, the densities of the solid and liquid states were 1525 kg m−3 (ambient temperature) and 1535 kg m−3 (at 60-70°C), respectively. Both mixtures show supercooling of about 23.4 and 34.1°C for the mixture with bischofite and MgCl2 · 6H2O, respectively. In addition, it was shown that supercooling may be reduced by increasing the quantity of material tested. Thereby, it was established that an inorganic mixture based on bischofite is a promising PCM for low-temperature thermal energy storage applications. [ABSTRACT FROM AUTHOR]

Brines coming from salted lakes such as that at the Atacama desert in Chile produce by-products or wastes which today are stored in the nearby from the production areas. Bischofite is one of those by-products, and therefore, its composition may vary from batch to batch. Because bischofite has been identified as a good candidate to be used as phase change material (PCM) for latent heat thermal energy storage, the influence of the variation of bischofite composite with its main impurities in this potential used needs to be evaluated. The main impurities of bischofite are the cations sodium, potassium and lithium and the anions chloride and sulfate. The results of this investigation established that the presence of KCl and NaCl in bischofite (up to 5 wt%) does not affect its use as PCM, because its melting enthalpy and temperature do not vary significantly. It is interesting that small contents of LiCl in bischofite do not change significantly its melting enthalpy but decrease the melting temperature. Such change may enable the usage of this material as PCM in other applications at lower temperatures. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The literature shows that inorganic phase change materials (PCM) have been very seldom microencapsulated, so this study aims to contribute to filling this research gap. Bischofite, a by-product from the non-metallic industry identified as having good potential to be used as inorganic PCM, was microencapsulated by means of a fluidized bed method with acrylic as polymer and chloroform as solvent, after compatibility studies of both several solvents and several polymers. The formation of bischofite and pure MgCl2 · 6H2O microcapsules was investigated and analyzed. Results showed an efficiency in microencapsulation of 95% could be achieved when using 2 min of fluidization time and 2 kg/h of atomization flow. The final microcapsules had excellent melting temperatures and enthalpy compared to the original PCM, 104.6 °C and 95 J/g for bischofite, and 95.3 and 118.3 for MgCl2 · 6H2O. [ABSTRACT FROM AUTHOR]

LiOH·H 2 O is used for preparation of alkaline batteries. The required characteristics of this compound are low levels of impurities and a specific particle size distribution. LiOH·H 2 O is produced from ore and brines. In northern Chile, lithium is produced from brines. This region presents particular desert climate conditions where water and energy are scarce. To help solve this problem, the conventional production process for battery grade LiOH·H 2 O was simulated and a modified process was developed, with an efficient consumption of energy and water, to improve the environmental sustainability of the plant, and greater process yield and product purity. Different configurations of the equipments were studied and for the best configurations the behavior of the modified process at different scenarios were simulated. It was found that the purity is independent of concentration used in feed to thickeners. The process yield increases in average 2.4% for modified process due to recycling operation. In modified process is obtained 28% more product mass, specific energy consumption decreases up to 4.8% and losses of Li/kg of product decreased by 83% compared to conventional process. The water consumption per kg of product in modified process is 1%–6.3%, being lower than in conventional process. The results presented can be considered as guidelines to address the optimization of the industrial process for obtaining the battery grade LiOH. [ABSTRACT FROM AUTHOR]

The objective of this work was to evaluate obtaining LiOH directly from brines with high LiCl concentrations using bipolar membrane electrodialysis by the analysis of Li+ ion transport phenomena. For this purpose, Neosepta BP and Fumasep FBM bipolar membranes were characterized by linear sweep voltammetry, and the Li+ transport number in cation-exchange membranes was determined. In addition, a laboratory-scale reactor was designed, constructed, and tested to develop experimental LiOH production tests. The selected LiCl concentration range, based on productive process concentrations for Salar de Atacama (Chile), was between 14 and 34 wt%. Concentration and current density effects on LiOH production, current efficiency, and specific electricity consumption were evaluated. The highest current efficiency obtained was 0.77 at initial concentrations of LiOH 0.5 wt% and LiCl 14 wt%. On the other hand, a concentrated LiOH solution (between 3.34 wt% and 4.35 wt%, with a solution purity between 96.0% and 95.4%, respectively) was obtained. The results of this work show the feasibility of LiOH production from concentrated brines by means of bipolar membrane electrodialysis, bringing the implementation of this technology closer to LiOH production on a larger scale. Moreover, being an electrochemical process, this could be driven by Solar PV, taking advantage of the high solar radiation conditions in the Atacama Desert in Chile. [ABSTRACT FROM AUTHOR]

In this study, an inorganic mixture of 40 wt% MgCl 2 ·6H 2 O and 60 wt% Mg(NO 3 ) 2 ·6H 2 O was impregnated into two types of the expanded graphite (EG): EG flakes and EG matrix. Different methods of preparation usually used in the organic composite preparation, such as direct blending, vacuum impregnation, ultrasonic impregnation and immersion were applied in this work. Considering the samples with EG matrix, it can be concluded that the optimal result of the encapsulation and ΔH ratio can be reached with the experimental time of 1, 3 and 4 h using the vacuum, ultrasound and immersion methods, respectively. Moreover, the percentage of encapsulation increases with the experimental time and with the EG percentage for the EG matrix and for the EG flakes, respectively. Concerning the supercooling phenomena, the results show that the presence of EG reduces the difference between fusion and crystallization temperature for up to 65%, acting as а nucleating agent. The resulting composite samples (CPCM) were proved to have good latent heat and a significant reduction of the supercooling effect, which eliminates the need to use nucleating agents, that are essential for pure PCM of 40 wt% MgCl 2 ·6H 2 O and 60 wt% Mg(NO 3 ) 2 ·6H 2 O. Moreover, using EG suppresses significantly the melting time which indicates the heat transfer enhance of the mixture. This circumstance could allow to empower the utilization of the mentioned mixture in different fields of thermal energy storage at low temperature. [ABSTRACT FROM AUTHOR]

Phase change materials (PCM) are characterized for storing a large amount of thermal energy while changing from one phase to another (generally solid-liquid states) at a specific temperature and presenting a high specific heat of phase change process. PCMs can be classified as organic, inorganic and eutectic. Such materials present some limitations, including subcooling, phase segregation, flammability, low thermal conductivity and thermal instability, among others. In order to overcome these problems, encapsulation of PCMs is being successfully developed, providing decreased subcooling, large heat transfer area, and controlling the volume change of the storage materials when the phase transition occurs. A considerable amount of studies has been published in the field of encapsulation methods for organic PCMs. Nevertheless, the information available on inorganic PCMs is scattered. Furthermore, the influence of the encapsulation techniques on thermophysical properties of PCMs is not reported in these reviews most of the time. Hence, the aim of this review is to summarize the encapsulation and characterization techniques for inorganic PCMs and to provide the analysis about the influence of synthesis parameters on thermophysical properties of encapsulated PCMs. Two principal types of encapsulated inorganic PCMs were found: core-shell PCMs (core-shell EPCMs) and shape stabilized PCMs (SS-PCMs). Classification of encapsulation methods of core-shell EPCMs and SS-PCMs are reported in this work. Among all the microencapsulation methods, inverse Pickering emulsion, electroplating, solvent evaporation–precipitation method and mechanical packaging are the most common methods described in the literature for the production of core-shell EPCM. On the other hand, for SS-PCMs, mainly sol-gel process, infiltration and impregnation encapsulation methods were found. Scientific works report a reduction in the heat of phase change for core-shell EPCMs. This is mostly because of the low content of salt in the final material. Moreover, an improvement of thermal conductivity was procured for SS-PCMs. Finally, PCM percentage, particle size, stirring rate, type of crosslinking agent and solvent properties were established as principal factors influencing the final properties of the encapsulated materials. For the best of our knowledge, this is the first profound review of encapsulation techniques for inorganic PCM. [ABSTRACT FROM AUTHOR]

In this study, two inorganic phase change materials (PCM) were tested to be used for thermal control of lithium-ion batteries. Paraffin wax was used as a reference material. To increase thermal conductivity, the PCMs were impregnated into the expanded graphite matrix, forming composite PCM (CPCM). Four types of Li-ion battery packs were manufactured to show the difference in performance between the packs with various CPCMs and No-CPCM. Electrical cycling studies at ambient temperature showed that at C/2 discharge the No-CPCM pack surpasses 35 °C, while all CPCM packs remain around 30 °C, demonstrating similar behavior. At 1C discharge, No-CPCM pack reaches 49 °C, whereas the CPCM packs do not exceed 40 °C. At 2C discharge, the No-CPCM pack overpassed the safety limit of 65 °C and was stopped before completing the first discharge. The CPCM packs successfully completed the cycling. Studies performed at 45 °C demonstrate a similar trend, but with higher peak temperatures. Nail penetration testing proved that the inorganic CPCMс inhibited the pack from self-accelerated degradation, successfully prevented thermal runaway propagation and potential explosion. Low cost and incombustibility make inorganic PCMs а viable alternative to the organic PCMs, with a positive impact on environmental and economic issues. Image 1 • Inorganic phase change materials are effective for Li-ion batteries thermal control. • Batteries are maintained at uniform temperatures and in safe temperature range. • Thermal runaway propagation was successfully prevented. [ABSTRACT FROM AUTHOR]