Two-shot formation

Two-shot formation process. The plates are formed in eells in a battery filled with H2SO4 solution of 1.15—1.10 relative density which serves as the formation electrolyte. After formation, the battery is set to a high current test discharge for 20 s, then it is recharged and the electrolyte is replaced with more concentrated solution of 1.30—1.32 relative density. This highly concentrated solution is diluted by the residual formation electrolyte in the plates and separators, and thus the required final electrolyte concentration of 1.28 relative density is reached. 

The more usual method of formation is to completely assemble the battery, fill it with electrolyte, and then apply the formation charge. This method is used for SLI and most stationary and traction batteries. A variety of formation conditions are used, similar to those for tank formation. The two major formation processes are the two-shot formation process (used for stationary and traction batteries) and the one-shot formation process (used for most SLI batteries). In the two-shot formation, the electrolyte is dumped to remove the low-density initial electrolyte and refilled with more concentrated electrolyte, chosen so that when this is mixed with the dilute initial acid residue which is absorbed in the elements or trapped in the case, the cell electrolyte will equilibrate at the desired density (Table 23.11). Typical values of the electrolyte specific gravity at full charge after formation are given in Table 23.12. 

A velocity shot survey is used to determine if the steam flow pattern is being altered near the well-bore. This survey involves the injection of cold water at the surface and the injection of a water-based tracer (e.g., iodine-131) down-hole. From the time it takes the tracer to travel between two detectors, it is possible to estimate the perforation depths at which the water preferentially enters the formation. 

Freshly prepared SSC was used in a series of one shot polymerizations using both cationic and anionic initiators as shown in Table I. The first entry C50N is a control experiment that demonstrates formation of a stable latex form the cationic monomer, styrene, and VBC with no sulfonate monomer. The next two entries were designed to give approximately equal amounts of (+) and (-) charges after quaternization, but both latexes were unstable at the precursor stage, perhaps because of partial hydrolysis of the sulfonyl chloride. When potassium persulfate was... 

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