Os autores gostariam de agradecer a National Science Foundation Award 1006568 para financiar este projeto.

1. Preparação Nano-VB 2 Nanoscopic VB 2 é diretamente sintetizada a partir de vanádio elementar e boro via bola de moagem em uma toupeira ração 01:02. <ol><li> Limpe a 50 ml de carboneto de tungstênio moagem jar e dez de 10 milímetros de carboneto de tungstênio bolas. Sob ar seco num forno a 100 ° C durante 1 hora para assegurar que toda a água tenha evaporado. </li><li> Limpe o interior do jarro de moagem para garantir que nenhum resíduo permanece, repita o passo 1.1 se resíduo é visível. </li><li> Purgar a antecâmara de um porta-luvas com argônio 3x por 10 minutos de cada vez. Transfira o frasco de moagem, bolas, e espátula limpa no argônio cheio porta-luvas. </li><li> Pesar o vanádio e os pós de boro numa razão molar de 1:2, 0,500 g de vanádio e de 0,212 g de boro dentro do frasco de moagem, adicionar as bolas, e selar o frasco de moagem. </li><li> Retire o frasco de moagem selado do porta-luvas, colocá-lo em um moinho de bolas planetário definido para 600 rpm e moinho para 4 horas. </li><li> Depois completion, permitir que o frasco de moagem a arrefecer até à temperatura ambiente antes da remoção do moinho de bolas. </li><li> Purgar a antecâmara de um porta-luvas com argônio 3x por 10 minutos de cada vez. Transfira o frasco de moagem, balão de fundo redondo, filme de parafina, espátula, e uma barra magnética na caixa de luva. </li><li> Aplicar o revestimento de óxido de zircónio com o preparado nanoscopic VB 2 como se segue: <ol><li> Dentro da caixa de luva recolher o nano-VB 2 previamente preparada usando uma espátula para raspar as paredes do frasco de moagem até que a maior parte da massa de partida foi recuperado. Pesar e transferir o recolhidas nano-VB 2 em um frasco de fundo redondo. </li><li> Pesam-se 3,5 por cento em peso de cloreto de zircónio em comparação com o VB recolhidos 2 e, em seguida, adicionar o pó para o balão de fundo redondo contendo o recolhidos nano-VB 2. </li><li> Adicionar uma barra magnética de agitação ao frasco e usando película de parafina selar a abertura antes da remoção da caixa de luva. Alternativamente, umsepto tem sido utilizado com resultados equivalentes Remover o frasco de fundo redondo da caixa de luva. </li><li> Usando uma seringa de 10 ml, transferir 10 ml de éter dietílico para o balão de fundo redondo. Cobrir rapidamente o buraco criado pela seringa no filme de parafina com uma peça adicional de Parafilm. </li><li> Misture o balão numa placa de agitação durante uma hora, em uma definição média. </li><li> Após uma hora, evapora-se o éter dietílico restante para fora do nano-2 VB utilizando um evaporador rotativo ou outro até que a configuração da bomba revestida de nano-VB 2 parece seco. </li><li> Depois de Zr revestido nano-VB 2 é completamente seco, coletar. </li></ol></li></ol> 2. Preparação de eletrólito <ol><li> Prepara-se uma mistura de uma solução 4 M de NaOH para utilização como electrólito e 4 M de KOH. (NOTA: Faça apenas o suficiente para durar algumas semanas, repita conforme necessário, para formar novas células). Electrólitos solução aquosa de hidróxido de NaOH e KOH foram explorados no passado variando em concentração ranging de 8 M a saturado. A combinação de NaOH 4 M e 4 M de KOH produz melhorou ligeiramente o desempenho da taxa elevada em comparação com os resultados anteriores, utilizando um electrólito de NaOH puro. </li></ol> 3. Desmontagem de zinco / Ar Baterias Consulte a tabela de regentes e materiais para detalhes sobre a fabricante da bateria eo número do modelo. <ol><li> Abrindo a célula de zinco / ar para a fabricação posterior do VB 2 / células de ar. <ol><li> Criar um corte no bordo do invólucro da célula de moedas com um alicate de corte diagonal. </li><li> Crimp fora afiada do lábio para fora. Depois de passar completamente em torno da célula, duas vezes, deve ser fácil de abrir. </li><li> Usando uma lâmina de barbear, empurre para cima nas bordas da tampa lentamente, forçar suavemente abrir a cela. NOTA: Pode demorar algum tempo para obter a célula aberta. Seja paciente e cuidado para não quebrar ou danificar qualquer parte ao fazer este passo. A célula terá de permanecer intacto. </li></ol></li><li> Preparação da bateria para uso <ol><li> Uma vez que a célula é aberta em duas partes (a tampa e a parte inferior) começam a retirar cuidadosamente o material de ânodo de zinco a partir da tampa e no fundo. </li><li> Remover o máximo possível de zinco sólido, com a lâmina de barbear. Não raspe o fundo, é importante para não danificar as peças. O separador (inferior) e os lados () formar uma junta de sobreposição única opaca que pode ser facilmente perfurado pela aplicação de demasiada pressão com a lâmina de barbear. Perfurar o separador irá resultar em danos no cátodo de ar. Adicionalmente, se a junta for perturbado a fiabilidade da célula a ser isolado electricamente é perdida. </li><li> Usando um cotonete, limpe cuidadosamente o zinco eo resíduo restante da tampa, inferior e separador. </li><li> Limpe a tampa e fora da célula com álcool isopropílico. </li></ol></li></ol> 4. Preparação de um 5 mAh eléctrodo de trabalho, com uma mistura de 70/30 seco <ol><li> Usando sintetizado Zr revestido nano-VB 2 como materialmente ativaai, pesam-se 0,0012 g por eléctrodo a ser fabricado (normalmente 5-10 células são testadas ao mesmo tempo) e transferir para um almofariz e pilão. </li><li> Adicionar 30% do VB pesava 2, 0,0005 g de negro de carbono de grafite (por eléctrodo), para o material activo num almofariz e pilão e moa durante 30 minutos. </li><li> Certifique-se de que não existem grandes aglomerados, visíveis de material e recolher pó. </li><li> Pesar aproximadamente 0,0017 g da mistura 70/30-powder per cap eletrodo limpo usando uma espátula. (Se a preparação de células múltiplas de uma só vez, transferir o material para a tampa do eléctrodo). </li><li> Adicionar uma gota de álcool isopropílico para cada tampa e agite em pó com uma espátula ou outra pequena ponta afiada até que não haja grumos e suspensão é distribuída uniformemente em toda a parte superior da tampa. </li><li> Permitir eléctrodos para secar durante 30 min. </li></ol> 5. VB 2-Air Assembléia celular - Método seco <ol><li> Montar células no sentido inverso do zinco / air célula com o eletrodo de trabalho, boné, de cabeça para baixo. </li><li> Organizar cada célula (a 5 - 10 a ser testado), em duas filas, os tampões em uma e os fundos correspondentes na outra. Inspeccionar cada tampa para garantir que o material do ânodo é uniformemente distribuída e não rachado. </li><li> Adicionar 27 uL de 4 M de KOH / 4 M de NaOH mistura de electrólito para cada separador. </li><li> Com cuidado, retire o excesso de eletrólito a partir do fundo usando algodão enxugando apenas uma vez dentro do fundo. </li><li> Retire cuidadosamente cada um dos fundos, entregá-los e colocá-los em cima das tampas de modo que o material anódico está em contato com o eletrólito. </li><li> Aplicar pressão e selar usando um epoxi de secagem rápida. </li></ol> 6. Nano-VB 2 Testing Cell / Air <ol><li> Uma vez que o processo de fabricação é concluído, as células coloque em uma cremalheira de descarga ou suporte da bateria. </li><li> Permitir que cada célula de um passo inicial de repouso de 10 minutos para assegurar que as células se equilibrar antes da descarga. </li><li> QuitaçãoAs células a uma carga constante de 3,000 Ω (ou uma carga desejada alternativa), utilizando um aparelho de bateria. </li><li> Após o passo de equilibração, fazer uma medição do potencial de circuito aberto. </li><li> Depois descarregar sob uma carga constante até que uma voltagem de 0,4 V de paragem ser atingido. </li><li> A eficiência de Coulomb pode então ser calculada a percentagem da capacidade de medição em relação ao ânodo teórico capacidade de descarga de electrões de onze Ah 4,060 kg -1. </li></ol>

<ol>
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J., Qu, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+review+on+air+cathodes+for+zinc+-+air+fuel+cells.">A review on air cathodes for zinc - air fuel cells.</a> Journal of Power Sources. 195, 1271-1291 (2010).</li><li>Yu, X., Licht, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+capacity+alkaline+super-iron+boride+battery.">High capacity alkaline super-iron boride battery.</a> Electrochimica Acta. 52, 8138-8143 (2007).</li><li>Licht, S., Wang, B., Ghosh, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Energetic+Iron(VI)+Chemistry:+The+Super-Iron+Battery.">Energetic Iron(VI) Chemistry: The Super-Iron Battery.</a> Science. 285, 1039-1042 (1990).</li><li>Licht, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+aluminum+batteries:+a+step+towards+derivation+of+superbatteries.">Novel aluminum batteries: a step towards derivation of superbatteries.</a> Colloids and Surfaces A: Physicochemical and Engineering Aspects. , 134-241 (1998).</li><li>Licht, S., Myung, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorinated+Graphites+as+Energetic+Cathodes+for+Nonaqueous+Al+Batteries.">Fluorinated Graphites as Energetic Cathodes for Nonaqueous Al Batteries.</a> Electrochem. Solid-State Lett. 5, A160-A163 (2002).</li><li>Licht, S., Ghosh, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+power+BaFe(VI)O4/MnO2+composite+cathode+alkaline+super-iron+batteries.">High power BaFe(VI)O4/MnO2 composite cathode alkaline super-iron batteries.</a> Journal of Power Sources. 109, 465-468 (2002).</li><li>Licht, S., Myung, N., Peramunage, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrahigh+Specific+Power+Electrochemistry,+Exemplified+by+Al/MnO4-+and+Cd/AgO+Redox+Chemistry.">Ultrahigh Specific Power Electrochemistry, Exemplified by Al/MnO4- and Cd/AgO Redox Chemistry.</a> The Journal of Physical Chemistry B. 102, 6780-6786 (1998).</li><li>Licht, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Aluminum/Sulfur+Battery+Discharge+in+the+High+Current+Domain.">Aluminum/Sulfur Battery Discharge in the High Current Domain.</a> J. 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S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Metal+Borides:+Competitive+High+Capacity+Anode+Materials+for+Aqueous+Primary+Batteries.">Metal Borides: Competitive High Capacity Anode Materials for Aqueous Primary Batteries.</a> Electrochemical and Solid-State. 7, A212-A215 (2004).</li><li>Licht, S., Yu, X., Qu, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+Alkaline+Redox+Couple:+Chemistry+of+the+Fe6+/B2-+Super-iron+Boride+Battery.">Novel Alkaline Redox Couple: Chemistry of the Fe6+/B2- Super-iron Boride Battery.</a> Chemical Communications. 2007, 2753-2755 (2007).</li><li>Licht, S., Wu, H., Yu, X., Wang, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Renewable+Highest+Capacity+VB2/Air+Energy+Storage.">Renewable Highest Capacity VB2/Air Energy Storage.</a> Chemical Communications. 2008, 3257-3259 (2008).</li><li>Light, S., Ghosh, S., Wang, B., Jiang, D., Asercion, J., Bergmann, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nanoparticle+Facilitated+Charge+Transfer+and+Voltage+of+a+High+Capacity+VB2+Anode.">Nanoparticle Facilitated Charge Transfer and Voltage of a High Capacity VB2 Anode.</a> Electrochemical and Solid-State. 14, 83-85 (2011).</li><li>Licht, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nano-VB2+Synthesis+from+Elemental+Vanadium+and+Boron:+Nano-VB2+Anode/Air+Batteries.">Nano-VB2 Synthesis from Elemental Vanadium and Boron: Nano-VB2 Anode/Air Batteries.</a> Electrochemical and Solid-State Letters. 15, A12-A14 (2012).</li></ol>

Os autores, Chris Rhodes, Ruben Lopez, Xuguang Li, Mahesh Waje e Mateus Mullings são funcionários da Lynntech Inc.

A construção da VB 2 / bateria ar, desta forma fornece a capacidade de estudar e investigar os onze elétrons por molécula de transferência de carga que ocorre, permitindo a possibilidade de uma nova bateria de alta capacidade. Se os resultados obtidos não demonstraram resultados reprodutíveis, assegurar que todo o material do ânodo de zinco foi removido a partir da bateria, que existe uma dispersão uniforme do material activo na tampa, e que as células são adequadamente coladas, sem quaisquer fugas...

Diboreto de vanádio como um ânodo tem entre a maior capacidade de carga volumétrico de qualquer material do ânodo. Este protocolo apresenta um método para estudar este material fascinante. Zinco metálico tem sido o material do ânodo predominante em sistemas primários aquosos, devido à alta volumétrica de dois elétrons do metal de zinco e gravimétricos capacidade de armazenamento de carga de 5,8 Kah L -1 e 820 Ah kg -1, respectivamente. * A bateria de zinco-carbono, conhecido como a célula Leclanché, foi introduzido pela primeira vez no século 19, combinando um ânodo de zinco com um dióxido de manganês (carbono coletor de corrente) cátodo em um eletrólito de cloreto de 1. A bateria alcalina comum utiliza o mesmo casal, mas substitui o eletrólito cloreto com um eletrólito de hidróxido alcalino aquoso. Juntos, zinco-carbono e pilhas alcalinas são a maioria de baterias primárias vendido 1. Quando o bióxido de manganês na célula alcalina é substituídopor um cátodo de ar, as capacidades de armazenamento de energia substancialmente mais elevados são atingidos. Esta bateria de zinco-ar utiliza o oxigênio do ar, e é comumente encontrado em baterias de aparelhos auditivos 1-3. A nossa busca de maior capacidade de armazenamento da bateria tem incidido sobre os materiais que podem ser transferidos vários elétrons por molécula 4-11. Entre a grande variedade de pares redox que exploramos, VB 2 destaca-se como um ânodo alcalino extraordinário capaz de liberar 11 elétrons por VB 2, com capacidade volumétrica e gravimétrica de 20,7 Kah L -1 e 4060 Ah kg -1, respectivamente. * Em 2004, Yang e colaboradores relataram a descarga de VB 2, mas também documentou o domínio estendido no qual VB 2 é suscetível à corrosão em meios alcalinos 12. Em 2007, relatou que um revestimento nas VB duas partículas impede essa corrosão 13, levando a demonstração da VB 2 ar / battery em 2008 14. Neste artigo, apresentamos um protocolo usado para investigar novos sistemas de metal / ar que empregam a tecnologia já desenvolvida para a célula de zinco / ar como aplicado ao VB 2 / câmara de ar. Um nanoscopicVB ânodo 2 é apresentado como um ânodo de alta densidade de energia de alta energia capaz de exibir uma reacção de oxidação de onze electrões aproximando a capacidade intrínseca teórica de 4060 Ah kg -1 em aumento da tensão da bateria e da capacidade de carga da bateria. A VB 2 / ar par usa um electrólito alcalino de KOH / NaOH, que emprega o mesmo cátodo de oxigénio do ar extraído a partir da célula de zinco / ar 1. O eletrocatalisador cátodo de carbono não é consumida durante a descarga. Existe uma necessidade para uma maior compreensão da VB 2 / sistema de ar, a fim de melhorar ainda mais o desempenho da célula. As propriedades eo desempenho de nanoscopic VB dois materiais podem ser exploradas usando tele configuração de célula da célula de zinco / ar 15,16. Electrochemical testes podem ser realizados para nanoscopic 2 VB para comparar o desempenho por meio da eficiência por cento em várias taxas.

<table border="1">
	<tbody>
		<tr>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>MATERIALS</td>
		</tr>
		<tr>
			<td>Boron</td>
			<td>Alfa Aesar</td>
			<td>11337</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Diethyl Ether</td>
			<td>J.T. Baker</td>
			<td>9244-06</td>
			<td>4L</td>
		</tr>
		<tr>
			<td>Epoxy</td>
			<td>Loctite</td>
			<td>&nbsp;</td>
			<td>Heavy Duty 5 min setting time</td>
		</tr>
		<tr>
			<td>Isopropyl Alcohol</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Panasonic 675 Zinc/Air cell</td>
			<td>Panasonic</td>
			<td>PR675H</td>
			<td>Made in Japan (not German)</td>
		</tr>
		<tr>
			<td>C-NERGY Super C65</td>
			<td>Timcal</td>
			<td>&nbsp;</td>
			<td>Graphitic carbon black</td>
		</tr>
		<tr>
			<td>Vanadium</td>
			<td>Aldrich</td>
			<td>262935</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Vanadium Diboride</td>
			<td>American Elements</td>
			<td>12007-37-3</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Zirconium Chloride</td>
			<td>Spectrum</td>
			<td>Z20001</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
			<td>EQUIPTMENT</td>
		</tr>
		<tr>
			<td>50-mL round bottom flask</td>
			<td>Fisher Scientific Co LLC</td>
			<td>CG151001</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Diagonal cutting pliers</td>
			<td>Hardware store</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Hot/stir plate</td>
			<td>IKA</td>
			<td>C-MAG HS 7</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Glove box</td>
			<td>Labconco</td>
			<td>Precision Basic</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Ten 10-mm tungsten carbide balls</td>
			<td>Lab Synergy</td>
			<td>55.0100.08</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Tungsten carbide milling jar</td>
			<td>Lab Synergy</td>
			<td>50.8600.00</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Razor blade</td>
			<td>Hardware store</td>
			<td>&nbsp;</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Retsch PM 100 planetary ball mill</td>
			<td>Retsch</td>
			<td>205400003</td>
			<td>&nbsp;</td>
		</tr>
		<tr>
			<td>Stir bar</td>
			<td>VWR International</td>
			<td>58947-140</td>
			<td>&nbsp;</td>
		</tr>
	</tbody>
</table>

fabrication of vb2/air cells for electrochemical testing

Uma técnica para investigar as propriedades e desempenho de novos sistemas de bateria multieletrônicos metal / ar é proposta e apresentada. Um método para sintetizar nanoscopic VB 2 é apresentada, bem como um procedimento passo-a-passo de aplicação de um revestimento de óxido de zircónio para as duas partículas VB para a estabilização no momento da alta. O processo de desmontagem de pilhas de zinco / ar existentes é mostrada, na construção de adição do novo eléctrodo de trabalho para substituir o zinco / ar de ânodo da célula convencional com um a nanoscopic VB 2 ânodo. Finalmente, a alta do VB completou 2 / bateria de ar é relatada. Nós mostramos que a utilização da célula de zinco / ar, como um banco de ensaio é útil para fornecer uma configuração consistente para estudar o desempenho de alta energia de alta capacidade nanoscopic VB 2 ânodo.

Teste electroquímico é realizado para determinar o desempenho de VB 2 / ar baterias. Os resultados obtidos para várias células fornecem evidência para a reprodutibilidade do desempenho da célula. Figura 1 compara a VB 2 / baterias de ar durante uma 3000 ohm (esquerda) e 1000 ohm (à direita) de descarga. Note-se que a tensão de descarga, bem como a fracção de 4,060 kg -1 Ah capacidade intrínseca é maior com a nanoscopic VB 2 ânodo comparado com o ?...

Watch this Scientific Journal Video about Fabrication of VB2/Air Cells for Electrochemical Testing at JoVE.com

Fabrication of VB2/Air Cells for Electrochemical Testing

Um protocolo para o estudo é apresentado de metal multieletrônicos / sistemas de baterias de ar, usando a tecnologia anterior, desenvolvido para a célula de zinco / ar. Teste electroquímico é então realizada nos baterias fabricados para avaliar o desempenho.

Fabricação de VB<sub&gt; 2</sub&gt; / Ar Células para Electrochemical Teste

A technique to investigate the properties and performance of new multi-electron metal/air battery systems is proposed and presented. A method for ...

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Fabrication of VB2/Air Cells for Electrochemical Testing

11.9K visualizações.  The George Washington University. Um protocolo para o estudo é apresentado de metal multieletrônicos / sistemas de baterias de ar, usando a tecnologia anterior, desenvolvido para a célula de zinco / ar. Teste electroquímico é então realizada nos baterias fabricados para avaliar o desempenho.

Vídeo: Fabrication of VB2/Air Cells for Electrochemical Testing

Construction and Testing of Coin Cells of Lithium Ion Batteries

Rechargeable lithium ion batteries have wide applications in electronics, where customers always demand more capacity and longer lifetime. Lithium ion batteries have also been considered to be used in electric and hybrid vehicles1 or even electrical grid stabilization systems2. All these applications simulate a dramatic increase in the research and development of battery materials3-7, including new materials3,8, doping9, nanostructuring10-13, coatings or surface modifications14-17 and novel binders18. Consequently, an increasing number of physicists, chemists and materials scientists have recently ventured into this area. Coin cells are widely used in research laboratories to test new battery materials; even for the research and development that target large-scale and high-power applications, small coin cells are often used to test the capacities and rate capabilities of new materials in the initial stage. 
 In 2010, we started a National Science Foundation (NSF) sponsored research project to investigate the surface adsorption and disordering in battery materials (grant no. DMR-1006515). In the initial stage of this project, we have struggled to learn the techniques of assembling and testing coin cells, which cannot be achieved without numerous help of other researchers in other universities (through frequent calls, email exchanges and two site visits). Thus, we feel that it is beneficial to document, by both text and video, a protocol of assembling and testing a coin cell, which will help other new researchers in this field. This effort represents the "Broader Impact" activities of our NSF project, and it will also help to educate and inspire students.
In this video article, we document a protocol to assemble a CR2032 coin cell with a LiCoO2 working electrode, a Li counter electrode, and (the mostly commonly used) polyvinylidene fluoride (PVDF) binder. To ensure new learners to readily repeat the protocol, we keep the protocol as specific and explicit as we can. However, it is important to note that in specific research and development work, many parameters adopted here can be varied. First, one can make coin cells of different sizes and test the working electrode against a counter electrode other than Li. Second, the amounts of C black and binder added into the working electrodes are often varied to suit the particular purpose of research; for example, large amounts of C black or even inert powder were added to the working electrode to test the "intrinsic" performance of cathode materials14. Third, better binders (other than PVDF) have also developed and used18. Finally, other types of electrolytes (instead of LiPF6) can also be used; in fact, certain high-voltage electrode materials will require the uses of special electrolytes7.

A protocol to construct and test coin cells of lithium ion batteries is described. The specific procedures of making a working electrode, preparing a counter electrode, assembling a cell inside a glovebox and testing the cell are presented.

Construção e Teste de Pilhas da moeda de baterias de lítio

Rechargeable lithium ion batteries have wide applications in electronics, where customers always demand more capacity and longer lifetime.  Lithium ion ...

Engenharia

Fabrication and Testing of Microfluidic Optomechanical Oscillators

Cavity optomechanics experiments that parametrically couple the phonon modes and photon modes have been investigated in various optical systems including microresonators. However, because of the increased acoustic radiative losses during direct liquid immersion of optomechanical devices, almost all published optomechanical experiments have been performed in solid phase. This paper discusses a recently introduced hollow microfluidic optomechanical resonator. Detailed methodology is provided to fabricate these ultra-high-Q microfluidic resonators, perform optomechanical testing, and measure radiation pressure-driven breathing mode and SBS-driven whispering gallery mode parametric vibrations. By confining liquids inside the capillary resonator, high mechanical- and optical- quality factors are simultaneously maintained.

Parametric optomechanical excitations have recently been experimentally demonstrated in microfluidic optomechanical resonators by means of optical radiation pressure and stimulated Brillouin scattering. This paper describes the fabrication of these microfluidic resonators along with methodologies for generating and verifying optomechanical oscillations.

Fabricação e Teste de microfluídicos optomechanical osciladores

Cavity optomechanics experiments that parametrically couple the phonon modes and photon modes have been investigated in various optical systems including ...

Fabrication Process of Silicone-based Dielectric Elastomer Actuators

This contribution demonstrates the fabrication process of dielectric elastomer transducers (DETs). DETs are stretchable capacitors consisting of an elastomeric dielectric membrane sandwiched between two compliant electrodes. The large actuation strains of these transducers when used as actuators (over 300% area strain) and their soft and compliant nature has been exploited for a wide range of applications, including electrically tunable optics, haptic feedback devices, wave-energy harvesting, deformable cell-culture devices, compliant grippers, and propulsion of a bio-inspired fish-like airship. In most cases, DETs are made with a commercial proprietary acrylic elastomer and with hand-applied electrodes of carbon powder or carbon grease. This combination leads to non-reproducible and slow actuators exhibiting viscoelastic creep and a short lifetime. We present here a complete process flow for the reproducible fabrication of DETs based on thin elastomeric silicone films, including casting of thin silicone membranes, membrane release and prestretching, patterning of robust compliant electrodes, assembly and testing. The membranes are cast on flexible polyethylene terephthalate (PET) substrates coated with a water-soluble sacrificial layer for ease of release. The electrodes consist of carbon black particles dispersed into a silicone matrix and patterned using a stamping technique, which leads to precisely-defined compliant electrodes that present a high adhesion to the dielectric membrane on which they are applied.

This manuscript shows the fabrication process for the manufacture of dielectric elastomer soft actuators based on silicone membranes. The three key stages of production are presented in detail: blade casting of thin silicone membranes; pad printing of compliant electrodes; and the assembly of all the components.

Processo de fabricação de base de silicone dielétricos Elastomer Atuadores

This contribution demonstrates the fabrication process of dielectric elastomer transducers (DETs). DETs are stretchable capacitors consisting of an ...

Protocol of Electrochemical Test and Characterization of Aprotic Li-O2 Battery

We demonstrate a method for electrochemical testing of an aprotic Li-O2 battery. An aprotic Li-O2 battery is made of a Li-metal anode, an aprotic electrolyte, and an O2-breathing cathode. The aprotic electrolyte is a solution of lithium salt with aprotic solvent; and porous carbon is commonly used as the cathode substrate. To improve the performance, an electrocatalyst is deposited onto the porous carbon substrate by certain deposition methods, such as atomic layer deposition (ALD) and wet-chemistry reaction. The as-prepared cathode materials are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray absorption near edge structure (XANES). A Swagelok-type cell, sealed in a glass chamber filled with pure O2, is used for the electrochemical test on a battery test system. The cells are tested under either capacity-controlled mode or voltage controlled mode. The reaction products are investigated by electron microscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, and Raman spectroscopy to study the possible pathway of oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). This protocol demonstrates a systematic and efficient arrangement of routine tests of the aprotic Li-O2 battery, including the electrochemical test and characterization of battery materials.

Protocol of Electrochemical Test and Characterization of Aprotic Li-O2 Battery

A protocol for the electrochemical testing of an aprotic Li-O2 battery with the preparation of electrodes and electrolytes and an introduction of the frequently used methods of characterization is presented here.

Protocolo de Eletroquímica Teste e Caracterização de aprótico Li-O<sub&gt; 2</sub&gt; bateria

We demonstrate a method for electrochemical testing of an aprotic Li-O2 battery. An aprotic Li-O2 battery is made of a Li-metal anode, an aprotic ...

Emission Spectroscopic Boundary Layer Investigation during Ablative Material Testing in Plasmatron

Ablative Thermal Protection Systems (TPS) allowed the first humans to safely return to Earth from the moon and are still considered as the only solution for future high-speed reentry missions. But despite the advancements made since Apollo, heat flux prediction remains an imperfect science and engineers resort to safety factors to determine the TPS thickness. This goes at the expense of embarked payload, hampering, for example, sample return missions. 
Ground testing in plasma wind-tunnels is currently the only affordable possibility for both material qualification and validation of material response codes. The subsonic 1.2MW Inductively Coupled Plasmatron facility at the von Karman Institute for Fluid Dynamics is able to reproduce a wide range of reentry environments. This protocol describes a procedure for the study of the gas/surface interaction on ablative materials in high enthalpy flows and presents sample results of a non-pyrolyzing, ablating carbon fiber precursor. With this publication, the authors envisage the definition of a standard procedure, facilitating comparison with other laboratories and contributing to ongoing efforts to improve heat shield reliability and reduce design uncertainties.
The described core techniques are non-intrusive methods to track the material recession with a high-speed camera along with the chemistry in the reactive boundary layer, probed by emission spectroscopy. Although optical emission spectroscopy is limited to line-of-sight measurements and is further constrained to electronically excited atoms and molecules, its simplicity and broad applicability still make it the technique of choice for analysis of the reactive boundary layer. Recession of the ablating sample further requires that the distance of the measurement location with respect to the surface is known at all times during the experiment. Calibration of the optical system of the applied three spectrometers allowed quantitative comparison. At the fiber scale, results from a post-test microscopy analysis are presented.

Development of new ablative materials and their numerical modeling requires extensive experimental investigation. This protocol describes procedures for material response characterization in plasma flows with the core techniques being non-intrusive methods to track the material recession along with the chemistry in the reactive boundary layer by emission spectroscopy.

Emissão espectroscópica Boundary Investigation Camada durante ablativo Teste de material em Plasmatron

Ablative Thermal Protection Systems (TPS) allowed the first humans to safely return to Earth from the moon and are still considered as the only solution ...

Electrochemical Etching and Characterization of Sharp Field Emission Points for Electron Impact Ionization

A new variation of the drop-off method for fabricating field emission points by electrochemically etching tungsten rods in a NaOH solution is described. The results of studies in which the etching current and the molarity of the NaOH solution used in the etching process were varied are presented. The investigation of the geometry of the tips, by imaging them with a scanning electron microscope, and by operating them in field emission mode is also described. The field emission tips produced are intended to be used as an electron beam source for ion production via electron impact ionization of background gas or vapor in Penning trap mass spectrometry applications.

A method for electrochemically etching field emission tips is presented. Etching parameters are characterized and the operation of the tips in field emission mode is investigated.

Electrochemical Gravura e Caracterização de pontas afiadas Field Emission for Electron Impact Ionização

A new variation of the drop-off method for fabricating field emission points by electrochemically etching tungsten rods in a NaOH solution is described. ...

Fabrication of White Light-emitting Electrochemical Cells with Stable Emission from Exciplexes

The authors present an approach for fabricating stable white light emission from polymer light-emitting electrochemical cells (PLECs) having an active layer which consists of blue-fluorescent poly(9,9-di-n-dodecylfluorenyl-2,7-diyl) (PFD) and &#960;-conjugated triphenylamine molecules. This white light emission originates from exciplexes formed between PFD and amines in electronically excited states. A device containing PFD, 4,4&#39;,4&#39;&#39;-tris[2-naphthyl(phenyl)amino]triphenylamine (2-TNATA), Poly(ethylene oxide) and K2CF3SO3 showed white light emission with Commission internationale de l&#39;&#233;clairage (CIE) coordinates of (0.33, 0.43) and a Color Rendering Index (CRI) of Ra = 73 at an applied voltage of 3.5 V. Constant voltage measurements showed that the CIE coordinates of (0.27, 0.37), Ra of 67, and the emission color observed immediately after application of a voltage of 5 V were nearly unchanged and stable after 300 sec.

The authors present a method for fabricating stable white-light-emitting electrochemical cells utilizing emission from exciplexes formed between a blue-emitting fluorene polymer and aromatic amines.

Fabricação de White Light-emitting células eletroquímicas com emissão estável de Exciplexes

The authors present an approach for fabricating stable white light emission from polymer light-emitting electrochemical cells (PLECs) having an active ...

Subsurface Defect Localization by Structured Heating Using Laser Projected Photothermal Thermography

The presented method is used to locate subsurface defects oriented perpendicularly to the surface. To achieve this, we create destructively interfering thermal wave fields that are disturbed by the defect. This effect is measured and used to locate the defect. We form the destructively interfering wave fields by using a modified projector. The original light engine of the projector is replaced with a fiber-coupled high-power diode laser. Its beam is shaped and aligned to the projector&#39;s spatial light modulator and optimized for optimal optical throughput and homogeneous projection by first characterizing the beam profile, and, second, correcting it mechanically and numerically. A high-performance infrared (IR) camera is set up according to the tight geometrical situation (including corrections of the geometrical image distortions) and the requirement to detect weak temperature oscillations at the sample surface. Data acquisition can be performed once a synchronization between the individual thermal wave field sources, the scanning stage, and the IR camera is established by using a dedicated experimental setup which needs to be tuned to the specific material being investigated. During data post-processing, the relevant information on the presence of a defect below the surface of the sample is extracted. It is retrieved from the oscillating part of the acquired thermal radiation coming from the so-called depletion line of the sample surface. The exact location of the defect is deduced from the analysis of the spatial-temporal shape of these oscillations in a final step. The method is reference-free and very sensitive to changes within the thermal wave field. So far, the method has been tested with steel samples but is applicable to different materials as well, in particular to temperature sensitive materials.

This method aims at locating vertical subsurface defects. Here, we couple a laser with a spatial light modulator and trigger its video input to heat a sample surface deterministically with two anti-phased modulated lines while acquiring highly resolved thermal images. The defect position is retrieved from evaluating thermal wave interference minima.

Localização de Defeitos Subsuperficiais por Aquecimento Estruturado usando a Termografia Fototérmica Projetada a Laser

The presented method is used to locate subsurface defects oriented perpendicularly to the surface. To achieve this, we create destructively interfering ...

Focused Ion Beam Fabrication of LiPON-based Solid-state Lithium-ion Nanobatteries for In Situ Testing

Solid-state electrolytes are a promising replacement for current organic liquid electrolytes, enabling higher energy densities and improved safety of lithium-ion (Li-ion) batteries. However, a number of setbacks prevent their integration into commercial devices. The main limiting factor is due to nanoscale phenomena occurring at the electrode/electrolyte interfaces, ultimately leading to degradation of battery operation. These key problems are highly challenging to observe and characterize as these batteries contain multiple buried interfaces. One approach for direct observation of interfacial phenomena in thin film batteries is through the fabrication of electrochemically active nanobatteries by a focused ion beam (FIB). As such, a reliable technique to fabricate nanobatteries was developed and demonstrated in recent work. Herein, a detailed protocol with a step-by-step process is presented to enable the reproduction of this nanobattery fabrication process. In particular, this technique was applied to a thin film battery consisting of LiCoO2/LiPON/a-Si, and has further been previously demonstrated by in situ cycling within a transmission electron microscope.

Focused Ion Beam Fabrication of LiPON-based Solid-state Lithium-ion Nanobatteries for In Situ Testing

A protocol for the fabrication of electrochemically active LiPON-based solid-state lithium-ion nanobatteries using a focused ion beam is presented.

Fabricação de feixe de íon focalizado de estado sólido baseados em LiPON de lítio-íon Nanobatteries para In Situ testes

Solid-state electrolytes are a promising replacement for current organic liquid electrolytes, enabling higher energy densities and improved safety of ...

Fabrication of Superhydrophobic Metal Surfaces for Anti-Icing Applications

Several ways to produce superhydrophobic metal surfaces are presented in this work. Aluminum was chosen as the metal substrate due to its wide use in industry. The wettability of the produced surface was analyzed by bouncing drop experiments and the topography was analyzed by confocal microscopy. In addition, we show various methodologies to measure its durability and anti-icing properties. Superhydrophobic surfaces hold a special texture that must be preserved to keep their water-repellency. To fabricate durable surfaces, we followed two strategies to incorporate a resistant texture. The first strategy is a direct incorporation of roughness to the metal substrate by acid etching. After this surface texturization, the surface energy was decreased by silanization or fluoropolymer deposition. The second strategy is the growth of a ceria layer (after surface texturization) that should enhance the surface hardness and corrosion resistance. The surface energy was decreased with a stearic acid film.
The durability of the superhydrophobic surfaces was examined by a particle impact test, mechanical wear by lateral abrasion, and UV-ozone resistance. The anti-icing properties were explored by studying the ability to repeal subcooled water, freezing delay, and ice adhesion.

We illustrate several methodologies to produce superhydrophobic metal surfaces and to explore their durability and anti-icing properties.

Fabricação de superfícies de Metal Superhydrophobic para aplicações antigelo

Several ways to produce superhydrophobic metal surfaces are presented in this work. Aluminum was chosen as the metal substrate due to its wide use in ...