Nickel sealed

Exceptions were found, for example. Rolls Royce RB 199 engines from the Tornado contained many particles from the abradable nickel seals. In instances such as these, it is imperative that the exceptions are included in future analyses. 

Storage. For receiving glycerol from standard 30.3-m (8000-gal) tank cars (36.3-t), a storage tank of 38—45-m ((10-12) x 10 — gal) capacity should be employed. Preferably it should be of stainless steel (304 or 316), of stainless- or nickel-clad steel, or of aluminum. Certain resin linings such as Lithcote have also been used. Glycerol does not seriously corrode steel tanks at room temperature but gradually absorbed moisture may have an effect. Therefore, tanks should be sealed with an air-breather trap. 

Odon acetate Odon, Saran polyethylene Teflon steel wood amber sealing wax hard mbber nickel, copper, brass, silver, old platinum sulfur acetate rayon polyester... 

The aimual production value of small, sealed nickel—cadmium cells is over 1.2 biUion. However, environmental considerations relating to cadmium are necessitating changes in the fabrication techniques, as well as recovery of failed cells. Battery system designers are switching to nickel —metal hydride (MH) cells for some appHcations, typically in "AA"-si2e cells, to increase capacity in the same volume and avoid the use of cadmium. 

To complete the assembly of a cell, the interleaved electrode groups are bolted to a cov er and the cover is sealed to a container. Originally, nickel-plated steel was the predominant material for cell containers but, more recently plastic containers have been used for a considerable proportion of pocket nickel-cadmium cells. Polyethylene, high impact polystyrene, and a copolymer of propylene and ethylene have been the most widely used plastics. 

Tlie cover assembly usually contains a safety v ent. Tlie most common type consists of a steel or nickel diaphragm built into the cov er and a bent point cut from the cov er. At a certain internal cell pressure, the diaphragm niov es to the bent point and is pierced. Some cylindrical sealed cells use one or more temiinal feed-throughs employing glass-to-metal or ceramic-to-metal techniques. 

Fig. 7. Section of disk-type cell where 1, is the cell cup 2, is the bottom insert 3, is the separator 4, is the negatwe electrode 5, is the positive electrode 6, is the nickel whe gauze 7, is the sealing washer 8, is the contact spring and 9, is the cell cover.

Lower cost and lower weight cylindrical cells have been made using plastic bound or pasted actwe material pressed into a metal screen. Tliese cells suffer slightly in utilization at high rates compared to a sintered-plate cylindrical cell, but they may be adequate for most applications. Tlie effect of temperature and discharge rate on the capacity of sealed nickel-cadmium cells is illustrated in Figure 8 and Table 3. 

Fig. 8. Discharge capacity of small sealed nickel—cadmium cells where the hiitial charge is 0.1 C x 16 h at 20°C and the discharge is 1 C at temperatures of...

CeU terminal connections are usuaUy brought out by two-threaded terminals that protmde through the ceU jar cover. They are usuaUy steel, brass, or copper with a hoUow coastmctioa. The plate leads are soldered ia place ia the ceater hoUow portioa of the terminal to effect an electrical contact and ceU seal. The terminal itself is potted iato the jar cover usiag epoxy-type pottiag compouads. NormaUy, terminal hardware is sUver-plated. However, for corrosioa resistance nickel-plating has been used. 

Some efforts toward sealed battery development (76) were made. However, a third electrode, an oxygen recombination electrode was required to reduce the cost of the system. High rate appHcations such as torpedo propulsion were investigated (77) and moderate success achieved using experimental nickel—zinc ceUs yielding energy densities of 35 W-h/kg at discharge rates of 8 C. A commercial nickel—zinc battery is considered to be the most likely... 

A number of manufacturers started commercial production of nickel—MH cells in 1991 (31—35). The initial products are "AA"-size, "Sub-C", and "C -size cells constmcted in a fashion similar to small sealed nickel —cadmium cells. Table 6 compares the Ovonics experimental cell and a similar sized nickel—cadmium cell. Ovonics also deUvered experimental electric vehicle cells, 22 A-h size, for testing. The charge—discharge of "AA" cells produced in Japan (Matsushita) are compared in Figure 22. 

A. Charkey, "Sealed Nickel—Zinc Cells," Proceedings of the 2Sth Annual Power Sources Conference Adantic City, N.J., 1972. 

H. Ogawa, M. Ikoma, H. Kawano, and I. Matsumoto, "Metal Hydride Electrode for High Energy Density Sealed Nickel—Metal Hydride Battery," Proceedings of the 16th International Power Sources Conference, UK, 1988. 

The bipolar plates are made from either Type 310 or Type 316 stainless steel, which is coated on the fuel side with nickel and aluminized in the seal area around the edge of the plates. Both internally and externally manifolded stacks have been developed. 

Fig. 14-6 Circuit diagram for a dc decoupling device with nickel-cadmium cell. (KE) insulated cable end sealing, (E) grounding installation, (1) grounding side bar (2) NiCd cell, 1.2 V (3) breakdown fuse (4,5) isolating links.

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