Vintage Radio Equip
The RX hi-voltage batteries were used in hearing aid's as were most of the subminature thyratron and hard tubes.
I remember opening up a 45 volt Burgess battery and being very impressed with the manner in which the multiple cells were stacked in order that the voltage could be delivered to the snap terminals.
Strangely enough the B batteries were very reliable I can never remember one failing. Not so with the rest of the components.
Richard Smith