The Development Of The Edison Storage Battery - 5

The Development Of The Edison Storage Battery - 5

  To follow Edison's trail in detail through the innumerable twists and turns of his

experimentation and research on the storage battery, during the past ten years, would not

be in keeping with the scope of this narrative, nor would it serve any useful purpose.

Besides, such details would fill a big volume. The narrative, however, would not be

complete without some mention of the general outline of his work, and reference may be

made briefly to a few of the chief items. And lest the reader think that the word

"innumerable" may have been carelessly or hastily used above, we would quote the reply

of one of the laboratory assistants when asked how many experiments had been made on

the Edison storage battery since the year 1900: "Goodness only knows! We used to

number our experiments consecutively from 1 to 10,000, and when we got up to 10,000

we turned back to 1 and ran up to 10,000 again, and so on. We ran through several series-

-I don't know how many, and have lost track of them now, but it was not far from fifty

thousand."

From the very first, Edison's broad idea of his storage battery was to make perforated

metallic containers having the active materials packed therein; nickel hydrate for the

positive and iron oxide for the negative plate. This plan has been adhered to throughout,

and has found its consummation in the present form of the completed commercial cell,

but in the middle ground which stands between the early crude beginnings and the

perfected type of to-day there lies a world of original thought, patient plodding, and

achievement.

The first necessity was naturally to obtain the best and purest compounds for active

materials. Edison found that comparatively little was known by manufacturing chemists

about nickel and iron oxides of the high grade and purity he required. Hence it became

necessary for him to establish his own chemical works and put them in charge of men

specially trained by himself, with whom he worked. This was the plant at Silver Lake,

above referred to. Here, for several years, there was ceaseless activity in the preparation

of these chemical compounds by every imaginable process and subsequent testing.

Edison's chief chemist says: "We left no stone unturned to find a way of making those

chemicals so that they would give the highest results. We carried on the experiments with

the two chemicals together. Sometimes the nickel would be ahead in the tests, and then

again it would fall behind. To stimulate us to greater improvement, Edison hung up a

card which showed the results of tests in milliampere-hours given by the experimental

elements as we tried them with the various grades of nickel and iron we had made. This

stirred up a great deal of ambition among the boys to push the figures up. Some of our

earliest tests showed around 300, but as we improved the material, they gradually crept

up to over 500. Just about that time Edison made a trip to Canada, and when he came

back we had made such good progress that the figures had crept up to about 1000. I well

remember how greatly he was pleased."

In speaking of the development of the negative element of the battery, Mr. Aylsworth

said: "In like manner the iron element had to be developed and improved; and finally the

iron, which had generally enjoyed superiority in capacity over its companion, the nickel

element, had to go in training in order to retain its lead, which was imperative, in order to

produce a uniform and constant voltage curve. In talking with me one day about the

difficulties under which we were working and contrasting them with the phonograph

experimentation, Edison said: `In phonographic work we can use our ears and our eyes,

aided with powerful microscopes; but in the battery our difficulties cannot be seen or

heard, but must be observed by our mind's eye!' And by reason of the employment of

such vision in the past, Edison is now able to see quite clearly through the forest of

difficulties after eliminating them one by one."

The size and shape of the containing pockets in the battery plates or elements and the

degree of their perforation were matters that received many years of close study and

experiment; indeed, there is still to- day constant work expended on their perfection,

although their present general form was decided upon several years ago. The mechanical

construction of the battery, as a whole, in its present form, compels instant admiration on

account of its beauty and completeness. Mr. Edison has spared neither thought, ingenuity,

labor, nor money in the effort to make it the most complete and efficient storage cell

obtainable, and the results show that his skill, judgment, and foresight have lost nothing

of the power that laid the foundation of, and built up, other great arts at each earlier stage

of his career.

Among the complex and numerous problems that presented themselves in the evolution

of the battery was the one concerning the internal conductivity of the positive unit. The

nickel hydrate was a poor electrical conductor, and although a metallic nickel pocket

might be filled with it, there would not be the desired electrical action unless a

conducting substance were mixed with it, and so incorporated and packed that there

would be good electrical contact throughout. This proved to be a most knotty and

intricate puzzle--tricky and evasive--always leading on and promising something, and at

the last slipping away leaving the work undone. Edison's remarkable patience and

persistence in dealing with this trying problem and in finally solving it successfully won

for him more than ordinary admiration from his associates. One of them, in speaking of

the seemingly interminable experiments to overcome this trouble, said: "I guess that

question of conductivity of the positive pocket brought lots of gray hairs to his head. I

never dreamed a man could have such patience and perseverance. Any other man than

Edison would have given the whole thing up a thousand times, but not he! Things looked

awfully blue to the whole bunch of us many a time, but he was always hopeful. I

remember one time things looked so dark to me that I had just about made up my mind to

throw up my job, but some good turn came just then and I didn't. Now I'm glad I held on,

for we've got a great future."