High rate discharge containers

Table 8 shows the results of a comparative study of three types of batteries. One contains polyethylene separators and the other two contain linter pulp separators, but are different sizes. High rate discharge performances of the three batteries under low temperature are shown in Figure 8. The battery with the polyethylene separator outperforms the battery with linter pulp separators which is of the same size, and equals the performance of the one which is larger. 

The Ragone plot shown in Fig. 7.13 obtained from the high-rate discharge curves is totally different from the ordinary one (Fig. 7.1), because it contains the nanosize effects in nanociystalline LiCo02. The Ragone plot clearly suggests that the energy density... 

From these data, the hydride cells contain approximately 30—50% more capacity than the Ni—Cd cells. The hydride cells exliibit somewhat lower high rate capabiUty and higher rates of self-discharge than nickel—cadmium cells. Life is reported to be 200—500 cycles. Though not yet in full production it has been estimated that these cells should be at a cost parity to nickel—cadmium cells on an energy basis. 

Ruidization is common in materials that contain a significant percentage of particles smaller than 100 pm (50). Fluidization segregation is likely to occur when fine materials are pneumatically conveyed when they are filled or discharged at high rates, or if gas counter-flow occurs. As with most segregation mechanisms, the more cohesive the material, the less likely it will segregate by this mechanism. 

Cell Life. Silver—zinc cells are usually manufactured as either low or high rate cells. Low rate cells contain fewer and thicker electrodes and have many layers of separator (up to the equivalent of 10 layers of cellophane). High rate cells, on the other hand, contain many thinner electrodes and have separator systems of the equivalent of three to four layers of cellophane. Approximately 10—30 cycles can be expected for high rate cells depending on the temperature of use, the rate of discharge, and methods of charging. Low rate cells have been satisfactorily used for 100 —300 cycles under the proper conditions. In general, the overall life of the silver—zinc cell with the separator systems normally in use is approximately 1—2 yr. 

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