This notebook covers the period March-June 1905. Most of the book contains notes, primarily by Edison, regarding storage batteries. Most of the entries pertain to electrochemical preparation of nickel flake and to electroplating cell components such as grids and pockets. In addition, there are notes relating to the loss of cell capacity associated with the swelling of the nickel pockets. There are also tests of cells using cobalt preparations, along with assays of nickel and cobalt ores. Several of the entries were witnessed by Frank L. Dyer. One page of notes has been inserted into the book. The pages are unnumbered. Approximately 200 pages have been used.