Enabling Reversible (De)Lithiation of Aluminum by using Bis(fluorosulfonyl)imide-Based Electrolytes

Aluminum, a cost-effective and abundant metal capable of alloying with Li up to around 1000 mAh g^-1 , is a very appealing anode material for high energy density lithium-ion batteries (LIBs). However, despite repeated efforts in the past three decades, reports presenting stable cycling performance are extremely rare. This study concerns recent findings on the highly reversible (de)lithiation of a micro-sized Al anode (m-Al) by using bis(fluorosulfonyl)imide (FSI)-based electrolytes. By using this kind of electrolyte, m-Al can deliver a specific capacity over 900 mAh g^-1 and superior Coulombic efficiency (96.8 %) to traditional carbonate- and glyme-based electrolytes (87.8 % and 88.1 %, respectively), which represents the best performance ever obtained for an Al anode without sophisticated structure design. The significantly improved electrochemical performance, which paves the way to realizing high-performance Al-based high energy density LIBs, can be attributed the peculiar solid-electrolyte interphase (SEI) formed by the FSI-containing electrolyte.

Towards High-Performance Aqueous Sodium-Ion Batteries: Stabilizing the Solid/Liquid Interface for NASICON-Type Na2 VTi(PO4 )3 using Concentrated Electrolytes

Aqueous Na-ion batteries may offer a solution to the cost and safety issues of high-energy batteries. However, substantial challenges remain in the development of electrode materials and electrolytes enabling high performance and long cycle life. Herein, we report the characterization of a symmetric Na-ion battery with a NASICON-type Na₂ VTi(PO₄ )₃ electrode material in conventional aqueous and "water-in-salt" electrolytes. Extremely stable cycling performance for 1000 cycles at a high rate (20 C) is found with the highly concentrated aqueous electrolytes owing to the formation of a resistive but protective interphase between the electrode and electrolyte. These results provide important insight for the development of aqueous Na-ion batteries with stable long-term cycling performance for large-scale energy storage.

Complementary Strategies Toward the Aqueous Processing of High-Voltage LiNi0.5 Mn1.5 O4 Lithium-Ion Cathodes

Increasing the environmental benignity of lithium-ion batteries is one of the greatest challenges for their large-scale deployment. Toward this end, we present herein a strategy to enable the aqueous processing of high-voltage LiNi_0.5 Mn_1.5 O₄ (LNMO) cathodes, which are considered highly, if not the most, promising for the realization of cobalt-free next-generation lithium-ion cathodes. Combining the addition of phosphoric acid with the cross-linking of sodium carboxymethyl cellulose by means of citric acid, aqueously processed electrodes with excellent performance are produced. The combined approach offers synergistic benefits, resulting in stable cycling performance and excellent coulombic efficiency (98.96 %) in lithium-metal cells. Remarkably, this approach can be easily incorporated into standard electrode preparation processes with no additional processing step.

Study of Water-Based Lithium Titanate Electrode Processing: The Role of pH and Binder Molecular Structure

This work elucidates the manufacturing of lithium titanate (Li₄Ti₅O₁₂, LTO) electrodes via the aqueous process using sodium carboxymethylcellulose (CMC), guar gum (GG) or pectin as binders. To avoid aluminum current collector dissolution due to the rising slurries' pH, phosphoric acid (PA) is used as a pH-modifier. The electrodes are characterized in terms of morphology, adhesion strength and electrochemical performance. In the absence of phosphoric acid, hydrogen evolution occurs upon coating the slurry onto the aluminum substrate, resulting in the formation of cavities in the coated electrode, as well as poor cohesion on the current collector itself. Consequently, the electrochemical performance of the coated electrodes is also improved by the addition of PA in the slurries. At a 5C rate, CMC/PA-based electrodes delivered 144 mAh·g^-1, while PA-free electrodes reached only 124 mAh·g^-1. When GG and pectin are used as binders, the adhesion of the coated layers to the current collector is reduced; however, the electrodes show comparable, if not slightly better, electrochemical performance than those based on CMC. Full lithium-ion cells, utilizing CMC/PA-made Li[Ni_0.33Mn_0.33Co_0.33]O₂ (NMC) cathodes and LTO anodes offer a stable discharge capacity of ~120 mAh·g^-1_(NMC) with high coulombic efficiencies.

High Temperature Stable Separator for Lithium Batteries Based on SiO₂ and Hydroxypropyl Guar Gum

A novel membrane based on silicon dioxide (SiO₂) and hydroxypropyl guar gum (HPG) as binder is presented and tested as a separator for lithium-ion batteries. The separator is made with renewable and low cost materials and an environmentally friendly manufacturing processing using only water as solvent. The separator offers superior wettability and high electrolyte uptake due to the optimized porosity and the good affinity of SiO₂ and guar gum microstructure towards organic liquid electrolytes. Additionally, the separator shows high thermal stability and no dimensional-shrinkage at high temperatures due to the use of the ceramic filler and the thermally stable natural polymer. The electrochemical tests show the good electrochemical stability of the separator in a wide range of potential, as well as its outstanding cycle performance.

[Analysis of scientific production of nurses from Minas Gerais published in nursing journals]

This is a descriptive, exploratory and retrospective study on the scientific production by nurses from Minas Gerais in BDENF Nursing journals from 1989 to 1998. The main objective was to characterize the scientific production by nurses from Minas Gerais published in the national nursing journals which comprise the BDENF. The names of 5.613 nurses from the records of COREn/MG were included in the database in order to find authors and their writings. Fifty-four authors and 87 writings were found with an average of 1.6 writings per author. The authors and co-authors who produce and publish are university professors working in collaboration with their peers.

[The labor force for elementary level nursing in the Belo Horizonte District]

This study refers to a survey on Nursing labor force without specific qualification, in the city of Belo Horizonte, aiming at offering help to Nursing Organizations (ABEn, COREn, Syndicates), Minas Gerais State Health Secretary Office and MG District Health Secretary Office, for the elaboration and release of professional purposes programs for this Nursing team. The research has been accomplished in 82 hospitals, having 2,662 respondents as sample, which corresponds to 74.6% of the studied population.

[Basic human needs--an identification of the need for continuing education based on a content analysis of nursing records]

Este estudo refere-se a uma análise do conteúdo das anotações de enfermagem contidas no formulário de observações de enfermagem, de pacientes de unidades médicas e cirúrgicas, de um hospital geral de grande porte de Belo Horizonte. O presente trabalho teve como objetivo geral a identificação da necessidade de um programa de educação continuada, sobre anotações de enfermagem, com ênfase nas necessidades humanas básicas. Constatou-se a necessidade urgente de se implementar um programa de educação continuada.

[The problem of orientating patients under diuresis control]

Neste estudo são verificados os tipos de orientação dados aos pacientes sob controle de diurese e o que eles sabem a respeito. O interesse demonstrado pelo paciente em saber do seu controle também é abordado.