152 E. F. ROEBER 



namics. There would be no such limitations with a carbon 

 cell. But the trouble is that such a cell is still a dream. 

 Theorists and practical men have attempted the solution 

 of the problem, but have equally failed. 



On the other hand, storage battery engineering has 

 passed with success through an extremely active career and 

 the outlook is bright for the future. As early as 1856 Gaston 

 Plante began his extended investigations on the formation 

 of the lead accumulator. His method was purely electro- 

 chemical. Starting with metallic lead sheets, he submitted 

 them to the action of the electric current in dilute sulphuric 

 acid. But since the cell had to be charged and discharged a 

 great many times, his method of formation required a very 

 long time and was expensive. The technical problem was, 

 therefore, to shorten the time of formation. 



Faure abroad, and Brush ni this country, devised in the 

 early 80's an improvement of the Plante cell, which consisted 

 in mechanically applying active material to a conducting 

 support. They thus produced instantly a plate, the manu- 

 facture of which by the Plante process would have required 

 several months. Immediately afterwards an extreme activity 

 began in storage battery invention, the goal being to avoid 

 the claims of the Brush patent. The outcome was a modifica- 

 tion of the original electrochemical Plante formation by 

 replacing the electrolyte of pure dilute sulphuric acid by an 

 oxidizing electrolyte. Moreover, purely chemical formation 

 without any current was also found practical. 



Along these general lines the successful lead battery of 

 to-day was developed. The number of United States patents 

 on this subject is legion, but the patents generally refer either 

 to details of construction or to composition of the electrolyte 

 for formation. Storage batteries have found very extended 

 use in direct current central stations and substations. In 

 fact, stationary batteries for such work represent at present 

 75 per cent of all the storage batteries manufactured, and for 

 this purpose the position of the lead cell seems secure. 



In recent years, however, the possibilities of electric 

 automobilism have encouraged inventors to search for a 

 battery of light weight and small size. The use of lead was 



