This folder contains correspondence and other documents relating to the use of Edison's storage battery in submarines and warships. Some of the documents refer to experiments by Edison on how to avoid the potentially dangerous discharge of hydrogen gas from submarine batteries. There are also references to plans to install Edison storage batteries on the Navy's E-2 submarine and to the sea tests that were conducted near the Brooklyn Navy Yard in November. An explosion aboard the E-2 on January 15, 1916, caused by excessive hydrogen created during the discharging and recharging of the battery, resulted in the death of five men. A Naval Board of Inquiry subsequently ruled that Edison batteries were too dangerous for use on submarines. Most of the documents are by Edison's chief engineer, Miller Reese Hutchison. Other correspondents include Secretary of the Navy Josephus Daniels, Undersecretary of the Navy Franklin D. Roosevelt, and Admirals Albert W. Grant and Robert S. Griffin. A few items bear marginalia by Edison.

Approximately 50 percent of the documents have been selected. The items not selected consist of unsolicited correspondence, letters of introduction, newspaper clippings, and routine documents pertaining to contracts between the U.S. Navy and the Edison Storage Battery Co.

A letter from Hutchison to Madeleine Edison inviting her to christen the new L-8 submarine (the first to be equipped with an Edison battery) and mentioning the E-2 battery contract can be found here.