“Dry” Storage Batteries
During the past year or two, so-called “dry” starting and lighting storage batteries have appeared on the market. This class includes batteries having “dry,” “semi-dry,” and “jelly” electrolytes. The claims made for these batteries are that there is nothing to evaporate and that the periodical addition of water is therefore unnecessary, that spilling and slopping of electrolyte is impossible, and that injurious sulphation does not take place.
The “dry” storage battery is not a new idea, for as much as thirty-five years ago, the Oerlikon Company of Switzerland manufactured “dry” electrolyte storage batteries in commercial quantities. These batteries were for a long time a distinct success for work requiring only low rates of discharge. For high rates of discharge the lack of diffusion, due to the absence of a liquid electrolyte, reduces the capacity. The lack of diffusion will cause a rapid drop in voltage when cranking the engine! and a slow recovery after the engine begins to run under its own power.
The manufacturers of the “dry” storage batteries, of course, claim that their batteries are more efficient and satisfactory than the standard “wet” battery, but it has been impossible to get sufficient data from the manufacturers to go into detail on the subject.
Several of the largest of “wet” battery manufacturers formerly made “dry” storage batteries for lighting and ignition service, but when starting motors came into use, discarded the “dry” batteries in favor of the present “wet” storage batteries.