Nickelic hydroxide paste

Reagents Nickelic hydroxide-paste Baryta water is treated with bromine water, and the resulting barium hypobromite is mixed with nickel sulfate solution and warmed. The proportions of Ba and Ni should be so adjusted that a gray precipitate is formed. It is filtered and well washed. The wet precipitate is stored in a weighing bottle with a well-fitting stopper. The paste can be kept for a long time. 

A precipitate of nickel hydroxide and a hydrogel of carrier prepared separately were mixed well for 20-30 hours by a kneader and the paste obtained was extruded into small sticks. 

A mixed paste of nickel hydroxide and silica gel was heated with water in an autoclave for 25 hours at 250° under 50 atm and then the product obtained was filtered. 

The sintered nickel substrate for the cathode is similar to that used for Ni-Cd and Ni-MH cell constructions. The nickel active materials are loaded into the sinter plate using either an aqueous (Bellcore) or alcoholic-based (Air Force or Pickett) electrochemical impregnation process. A 5-10% cobalt additive is deposited with nickel hydroxide to improve charge acceptance. These electrodes have a significantly longer cycle life over the standard vacuum impregnated or pasted nickel electrodes used in commercial Ni-Cd cells. 

The sintered-type electrode is formed by filling of the nickel hydroxide active material into the sintered nickel porous layer on the punched steel metal. The pasted-type electrode is formed by filling of the nickel hydroxide active material into the formed nickel substrate with very high porosity. In the sintering layer of the sintered-type electrode, the pore size is around 10 pm and the porosity is approximately 75 %. On the coti-trary, in the formed nickel substrate of the pasted-type electrode, the pore size is around 500 pm and the porosity is approximately 95 %. Therefore, the sintered-type electrode is suitable for a high power use, and the pasted-type electrode is used for a high capacity battery [4]. 

Nickel hydroxide active material is provided by reacting nickel sulfate solution and an alkaline solution. A part of nickel of nickel hydroxide is substituted for Zn and Co for the improvement of the battery performance. The theory capacity of nickel hydroxide is 289 mAh/g by supposing one electron reaction. The utilization of nickel hydroxide of a sintered-type electrode is approximately 100 %, but that of a pasted-type electrode without a conductive additive is around 65 %. The improvement of the utilization is enabled by forming CoOOH conductive networks between nickel hydroxide particles. The cobalt compound (Co, CoO, Co(OH>2) is filled into the formed nickel substrate with nickel hydroxide as an additive. The Co compounds form a conductive network as CoOOH by charging. To improve the conductivity of the cobalt conductive layer, Co(OH)2 layer coating to the surface of nickel hydroxide particles and the oxidation treatment in an alkaline solution of this coated powder are suggested. 

Sintered Versus Pasted Nickel Hydroxide Positive... 

As mentioned previously, one type of niekel hydroxide is by far the most common—a high density spherieal type for use in pasted electrodes which became commercial around 1990. - " High density spherieal niekel hydroxide is made in a precipitation process where metal salts sueh as nickel sulfate are reaeted with caustic such as NaOH in the presence of ammonia. The niekel source may have additives such as cobalt and zinc to enhance per-formanee. The important physieal parameters within this type of nickel hydroxide are ... 

Standard solutions, a solution of nickel in acid with a quoted mass/volume concentration, a solution of sodium hydroxide with a quoted concentration as a molarity and a solution of pesticides with quoted mass/volume concentrations. Matrix RMs - natural materials, river sediment with quoted concentrations of metals, milk powder with a quoted fat content and crab paste with quoted concentrations of trace elements. 

The catalysts were prepared using 50 wt.% of ZSM-5 with varying level of ion exchange. The zeolite was subjected to two- or one-step treatment with ammonium chloride solution. Zeolite was incorporated by.a method in which zeolite and aluminium hydroxide were pasted, mixed and extruded. The catalysts contained 8 or 12 wt % of NiO 4 wt.% were introduced in the course of the carrier forming process, the remaining portion of nickel being loaded by impregnation. 

All coppei -nickel catalysts were prepared from the magnetically pure copper which was itself completely inactive in the hydrogenation of benzene under the conditions described below. Cupric hydroxide was precipitated from a nitrate solution by dilute ammonium hydroxide solution so that the supernatant liquid was faintly colored by the copper-ammonia complex. The precipitate was filtered and washed. Nickel nitrate in water solution was now added in the proportion desired, and the mixture was stirred to a paste of even consistency. It was dried at 95°, ignited at 180° for 36 hours, and finally at 400° for 20 hours. The oxide mixture was reduced in purified hydrogen at 150° for 20 hours. Most finished catalysts contained 1.0 per cent of nickel. 

Batteries that require a liquid electrolyte are called wet batteries. Corrosive battery fluid refers to either acid electrolytes syn. battery acid, like the common lead-acid automobile battery which uses a solution of sulphuric acid, or alkali electrolytes syn. alkaline corrosive battery fluid, like potassium hydroxide (1310-58-3) solutions in nickel-cadmium and other alkaline battery systems. Dry batteries or dry cells, like all primary batteries, use electrolytes immobilized in pastes, gels, or absorbed into separator materials. Some batteries are loaded with a dry, solid chemical (e.g., potassium hydroxide) which is diluted with water to become a liquid electrolyte. The hazards associated with handling and transportation prior to use are thereby reduced. 

The disappearance of the black color of the higher nickel oxides on treatment with hydrogen peroxide affords a means for the detection of the latter. It is best to use a paste made from nickeP i hydroxide and an inert colorless substance, such as barium sulfate. It is not feasible to use filter paper... 

Most silver-cadmium cells contain cadmium electrodes that are manufactured by pressed-power or pasting techniques. Although other methods have been used, such as impregnating nickel plaque with cadrnium salts, as is done for nickel-cadmium cells, the most common method in silver-cadmium cells is to press or paste a mixture of cadmium oxide or cadmium hydroxide with a binder onto a silver or nickel grid. These processes are similar to those used for the pressed and pasted zinc electrodes. 

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