This type of battery was once very popular in communication devices. In local battery (magneto) service, a pair of them, designed for intermittent service, was used to supply local battery. Because replacement was a maintenance expense, they were expected to last a long time.
At Western Union, they were used in various ways, but a major application was to wind the springs of the very popular Western Union Clock*. In 1955, WU bought 75,000 No. 6 dry cells a year (as well as 75,000 "D" batteries).
Because of the widespread use, WU developed automated tests to determine battery life. Precise loads were imposed on the battery at periodic times and the voltage output tested.
An interesting article describing the batteries, their applications, and testing procedures may found in the telecom archives at:
(page forward or backward to see other articles from 1955).
*In the 1950s and 1960s Western Union began an aggressive modernization program to improve it services, the appearance of its offices, and its public image. Yet the synchronized clock network retained a very old fashioned looking clock that looked very out of place in a modern office. The Bell System stretched the life of some old telephone sets by simply adding a modern case over old apparatus (the 302 -> 5302, which looked like a modern 500 set). WE could've repackaged the clock case and clock face, maintaining the internal mechanism.