This notebook contains one dated entry for August, with no year given. It was probably used in 1905 or 1906. All entries are by Edison. Most of the book consists of a log of storage battery cell tests. Included are notes regarding which cells used nickel or cobalt, the number of tamps used to pack the metal flake, and whether the cells were run hot (with heated solution) or cold. Near the end of the book are two pages of ore assays. The front cover is labeled "Storage Battery Important Data." The pages are unnumbered. Approximately 40 pages have been used.