Electrode iron sulfide

At the same time, A1 helps NaAlCl4 melt to penetrate into the pores in electrode. Iron sulfide is added in order to stabilize the Ni particle size. The plateau can be found in the potential region in 2-1.6 V. 

Solubility data (pA sp) for two dozen hexacyanoferrate(II) and hexacyanoferrate(III) salts, and Pourbaix (pe/pH) diagrams for iron-cyanide-water, iron-sulfide-cyanide-(hydr)oxide, iron-arsenate-cyanide-(hydr)oxide, and iron-copper-cyanide-sulfide-(hydr)oxide, are given in a review ostensibly dedicated to hydrometallurgical extraction of gold and silver. " The electrochemistry of Prussian Blue and related complexes, in the form of thin films on electrodes, has been reviewed. ... 

The upper electrode is grounded to ihe vessel and any conductive material between ihe electrodes can cause a short circuit. The charged electrode can also short to the vessel or to the oil water interface. Any accumulation of water, bsltw, iron sulfides, or similar material can result in a short circuit. The most common cause of short ing is an interface buildup. 

In these cells readily available substances are used as active materials -molten sodium and sulfur working in contact with a solid electrolyte (sodium beta-aluminate). Sulfur-sodium storage cells show rather large values of specific electrical energy. Their working temperature is 350 C, i.e. before use they must be heated up to this temperature. Storage cells with electrodes from iron sulfide and lithium alloys with a melt of chlorides as electrolyte exhibit similar properties. The working temperature of these cells is about 400°C. 

Resistance to current flow also occurs as a consequence of solid corrosion product buildup on the metal surface. This phenomenon is most pronounced in environments containing H2S. Iron sulfide is a semiconductor whose conducting properties depend on the nature of the environment. It had been observed [39] that the anodic and cathodic polarization curves on iron sulfide covered electrodes are linear rather than exponential. In this case, the current flow is entirely controlled by the charge transfer across the interphase (not interface) consisting of FeS. The polarization admittance (1/Rp) becomes... 

Shustova SI, Ravdel BA, Tikhonov KI. (1985) Electrode-Reactions in the Reduction of Iron Sulfides in Propylene Carbonate. Sov Electrochem 21 524-527... 

In order to circumvent safety problems and to reach a longer cycle life, lithiated iron sulfide, Li2FeS2, was proposed as electrode material. ... 

The lithium/iron sulfide rechargeable battery system is another high-temperature system and must be operated above 400°C so that the salt mixture (LiCl-KCl) used as an electrolyte remains molten (see Chapter 41). The negative electrode is lithium, which is alloyed with aluminum or silicon, and the positive electrode can be either iron monosulfide or iron disulfide. No development is being performed on these technologies at this time because room temperature battery systems are showing comparable performance. 

The main interest in high temperature batteries such as lithium/iron sulfide, sodium/ sulfur, and sodium/nickel chloride is for electric vehicle applications due to their high specific power and energy possibilities. The replacement of the liquid lithium electrode with a solid LiAl alloy alleviated many of the safety concerns that plagued the other two systems, which are based on a liquid sodium electrode. In 1991, the United States Advanced Battery Consortium (USABC) selected the bipolar molten-salt LiAl/FeS2 battery to be developed as... 

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