This notebook covers the period January 1904-February 1905. It contains notes, primarily by Jonas Walter Aylsworth, regarding storage battery experiments. There are additional entries by Edison and by at least one unidentified experimenter. The tests are numbered from 998 through 2204 and pertain to nickel flake for the cells. The entry for test 2195 contains Aylsworth's discussion of reasons for the loss of capacity in the commercial cells, and the tests that follow are attempts to overcome this problem. The front cover is labeled "Storage Battery Experiments #998 to 2204 J W A" and "Somewhat Important." The inside front cover is inscribed "Record of Experiments Edison Storage Battery Co. From Feb 3/04 to ." The pages are unnumbered, and at least one page has been removed from the book. Approximately 190 pages have been used.

Only tests 998-1065, which contain entries by Edison, and tests 2195-2204 regarding the capacity problem have been selected.