Search

Single-ion lithium conducting polymer electrolytes based on delocalized borate groups have been designed and synthesized by rapid UV-photopolymerisation. For this purpose, three different functional lithium boron sp3 anionic monomers, containing fluorinated, ethoxy, or a blend of both functionalities have been synthesized. These monomers were photopolymerized in the presence of a PEG-di-acrylate crosslinker and tetraglyme as plasticizer. By this method, gel polymer electrolytes (SIPEs) endowed with lithium single-ion conduction were prepared. The impact generated by the different functionalities of the borate groups and the addition of plasticizer on the electrochemical and ion conducting properties of the synthesized polymer electrolytes are analyzed in detail. These polymer electrolytes showed high ionic conductivity (1.71·10 -4 S·cm-1 at 25 °C) and high lithium transference number values (up to 0.85). Finally, they were investigated as solid electrolytes in lithium metal symmetrical cells showing good performance (<0.85 V at ±0.2 mA·cm-2 for 175 h).

Colombia and Chile have been a country that has always been immersed in violence, corrupt governments and deaths of innocent people who demonstrate in the hope that the state will listen to them and guarantee their rights fairly. That is why it was decided to carry out this research work on the right to protest in these two governments with the aim of exposing the causes, circumstances and social and political effects suffered by these countries, taking into account the motives of the protests they had. place during the period of the year 2020-2021 and a comparison was carried out with the purpose of identifying the similarities and differences in the contexts of these countries, likewise the fundamental and human rights that were violated to the population and individuals were identified belonging to the public force in the period of the protests and finally an analysis was carried out from the Machiavellian perspective, which has been applied by the states in question with respect to the mechanisms implemented in response to the demonstrations. However, certain violent and disruptive responses from the governments under study were obtained as a result, which directly affect fundamental rights, in addition, with the actions of these states, a certain inconsistency is evident with what was proposed by the author Machiavelli, in As for contemplating the protests as suitable means to be able to know the disagreements that the people present in order to strengthen the government, on the other hand, it was found that not in all aspects these governments operate contrary to what was proposed by the author in question due Because, as he establishes in his work, the prince, the important thing is to maintain power regardless of the means or consequences involved in achieving it., Colombia y Chile han sido países que siempre se han encontrado inmersos en la violencia, en gobiernos corruptos y en las muertes de personas inocentes que se manifiestan con la esperanza de que el Estado las escuche y garantice sus derechos equitativamente. Teniendo en cuenta ello, se decidió realizar este artículo de investigación de carácter científico y tecnológico sobre el derecho a la protesta en los gobiernos en mención, con el propósito de exponer las causas, circunstancias y efectos sociopolíticos que sufren dichos países, considerando los motivos de las protestas que tuvieron lugar durante el período de los años 2020-2021, y se llevó a cabo una comparación con el objeto de identificar las similitudes y diferencias en los contextos de estos gobiernos; así mismo, se determinaron los derechos fundamentales y humanos que fueron vulnerados a la población y a los individuos pertenecientes a la fuerza pública en el lapso de las protestas. Por último, se hizo un análisis desde la perspectiva maquiavélica, misma que ha sido aplicada por los Estados anteriormente indicados con respecto a los mecanismos implementados como respuesta a las manifestaciones, tal como el uso gradual de la fuerza. Ahora bien, se recibió una respuesta violenta y quebrantadora por parte de los gobiernos objeto de estudio, la cual afecta directamente los derechos fundamentales, evidenciándose cierta incongruencia con lo propuesto por el autor Maquiavelo en cuanto a contemplar las protestas como medios idóneos para poder conocer las inconformidades que presenta el pueblo, a fin de poder fortalecer el gobierno.

Single-ion lithium conducting polymer electrolytes based on delocalized borate groups have been designed and synthesized by rapid UV-photopolymerisation. For this purpose, three different functional lithium boron sp3 anionic monomers, containing fluorinated, ethoxy, or a blend of both functionalities have been synthesized. These monomers were photopolymerized in the presence of a PEG-di-acrylate crosslinker and tetraglyme as plasticizer. By this method, gel polymer electrolytes (SIPEs) endowed with lithium single-ion conduction were prepared. The impact generated by the different functionalities of the borate groups and the addition of plasticizer on the electrochemical and ion conducting properties of the synthesized polymer electrolytes are analyzed in detail. These polymer electrolytes showed high ionic conductivity (1.71·10 -4 S·cm-1 at 25 °C) and high lithium transference number values (up to 0.85). Finally, they were investigated as solid electrolytes in lithium metal symmetrical cells showing good performance (<0.85 V at ±0.2 mA·cm-2 for 175 h).

Lithium-air/O-2 batteries are a promising battery technology for automotive applications due to their high energy density. However, many challenges need to be solved, particularly the high reactivity of the electrolyte with oxygen superoxide radicals and its low cyclability. In this work, we present a simple and fast way to prepare polymer-based iongel soft solid electrolytes. Thermally and mechanically stable iongels are prepared by fast UV-photopolymerisation exhibiting a high ionic conductivity (similar to 1.2 x 10(-3) S cm(-1) at 25 degrees C). When used as solid electrolytes in lithium symmetrical cells, they can withstand a critical current density of 0.5 mA cm(-2). Performance in Li-O-2 cells showed capacities as large as 3.3 mAh cm(-2), and cycling capability of 25 cycles, exceeding results on liquid-counterpart cells.

Lithium-O2 batteries represent one of the most appealing candidates for battery electric vehicles (BEV) due to its remarkable theoretical high energy density, similar to fossil fuels. Solid polymer electrolytes represent a plausible solution to tackle some of the challenges associated to conventional liquid-based Li-O2 batteries, including safety concerns. Herein, cross-linked robust gel polymer electrolytes (GPE) based on poly(ethylene glycol) dimethacrylate (PEGDM) and tetraethylene glycol dimethyl ether (TEGDME) as plasticizer are prepared by rapid UV-photopolymerization. Both types of robust GPEs presented high ionic conductivity at room temperature (1.6·10−4 S·cm−1 and 1.4·10−3 S·cm−1 for single ion or dual ion, respectively). Both types of GPEs, single ion and dual ion lithium conductors, have been compared for the first time on Li-O2 cells. First, their performance was investigated in symmetrical Li|Li cells. In this case, the dual-ion GPE showed an outstanding behavior where the overpotential was <0.2 V vs Li0/Li+ for more than 40 hours at a current density as highs as ±1 mA·cm−2. On the other hand, in full Li-O2 configuration, the single ion GPE cell showed superior discharge capacity, up to 2.38 mAh·cm−2. A dynamic discharge characterization technique is proposed here as a method for evaluating the polarization effect in electrolytes during discharge in an easy, quantifiable and reproducible manner.

This communication reports a family of single-ion lithium conducting polymer electrolytes based on highly delocalized borate groups is reported. The effect of the nature of the substituents on the boron atom on the ionic conductivity of the resultant methacrylic polymers was analyzed. To the best of our knowledge the lithium borate polymers endowed with flexible and electron-withdrawing substituents presents the highest ionic conductivity reported for a lithium single-ion conducting homopolymer (1.65×10−4 S cm−1 at 60 °C). This together with its high lithium transference number tLi+= =0.93 and electrochemical stability window of 4.2 V vs Li0/Li+ show promise for application in lithium batteries. To illustrate this, a lithium borate monomer was integrated into a single-ion gel polymer electrolyte which showed good performance on lithium symmetrical cells (<0.85 V at ±0.2 mA cm−2 for 175 h).

Hybrid solid electrolytes which combine the properties of inorganic and polymeric ion conductors are being investigated for lithium batteries which use lithium metal anodes. The number of inorganic/polymer compositions and their synergy in ion-conducting properties are limited by the hybrid fabrication method and the limited compatibility between both types of materials. Here we report a hybrid solid electrolyte formed by a poly(ethylene glycol) type single-ion polymer network and ceramic garnet-type nanoparticles of Li7−3XAlXLa3Zr2O12 (LLZO) with very high lithium conductivity. The combination of a lithium-single ion polymer matrix with LLZO inorganic particles results in flexible free-standing films by using a fast UV-photopolymerization process with facile control of its composition. This methodology showed excellent dispersion of the LLZO nanoparticles within the gel polymer network with up to 50 wt% ceramic content, as shown in the enviromental ESEM images. These hybrid electrolytes have high ionic conductivity values (1.4 × 10−4 S cm−1 at 25 °C) and high lithium transference number as compared to previous hybrid electrolytes. The effect of LLZO nanoparticle content on the lithium transport was investigated in detail using solid-state nuclear magnetic resonance spectroscopy (NMR). Finally, determination of the critical current density (CCD) before lithium dendrites are initiated has been carried out on both pristine and hybrid electrolytes, so as to assess their potential as solid electrolytes for lithium metal batteries.