These six folio notebooks were used during the period August 1904-September 1911 to graph the performance of various batteries. The first four books relate to Edison's alkaline storage batteries. Included are tests of experimental cells as well as the A4 and A8 production models. The fifth and sixth books contain data on cells manufactured by competitors of the Edison Storage Battery Co., including the Columbia, Eveready, Exide, National, and Philadelphia brands. Most of the graphs indicate that the data was collected or approved by Walter E. Holland. The plots were drawn by Holland, "A. C." (probably Alvin D. Caskey), and others. Each graph provides information on charge and discharge conditions, and most pertain to several cells or several tests. Titles are stamped on the front cover of each book. The four volumes relating to Edison storage batteries have been selected.