PRIMARY BATTERIES


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PRIMARY BATTERIES
PRIMARY BATTERIES143. The standard Daniell cell is a primary cell that has an emf which is practically 1 V when delivering a constant current. There are many forms of Daniell cell, each of which is particularly adapted to certain services, but all have very nearly the same emf (1.07 + V). The emf is not changed appreciably by the degree of concentration of the solutions, by the temperature, by the resistance, or by the purity of the zinc or copper, etc. In short, it makes a very good rough-and-ready standard.A very good model is that used by the British Post Office. The jar is made with two compartments, one containing a porous cup immersed in water, in which are placed a copper plate and crystals of copper sulfate, the other containing a zinc plate and a 5…
Citation
Terrell Croft; Frederic P. Hartwell; Wilford I. Summers: American Electricians' Handbook, Sixteenth Edition. PRIMARY BATTERIES, Chapter (McGraw-Hill Professional, 2013), AccessEngineering Export