to mine the ore body were not successful, and he abandoned his mining claim in 1903. A street in Falconbridge, as well as the Edison Building, which served as the head office of Falconbridge Mines, are named for him. Rechargeable battery In the late 1890s, Edison worked on developing a lighter, more efficient rechargeable battery (at that time called an "accumulator"). He looked on them as something customers could use to power their phonographs but saw other uses for an improved battery, including electric automobiles. The then available lead acid rechargeable batteries were not very efficient and that market was already tied up by other companies so Edison pursued using alkaline instead of acid. He had his lab work on many types of materials (going through some 10,000 combinations), eventually settling on a nickel-iron combination. Besides his experimenting Edison also probably had access to the 1899 patents for a nickel–iron battery by the Swedish inventor Waldemar Jungner. Edison obtained a US and European patent for his nickel–iron battery in 1901 and founded the Edison Storage Battery Company, and by 1904 it had 450 people working there. The first rechargeable batteries they produced were for electric cars, but there were many defects, with customers complaining about the product. When the capital of the company was exhausted, Edison paid for the company with his private money. Edison did not demonstrate a mature product until 1910: a very efficient and durable nickel-iron-battery with lye as the electrolyte. The nickel–iron battery was never very successful; by the time it was ready, electric cars were disappearing, and lead acid batteries had become the standard for turning over gas-powered car starter motors. Chemicals At the start of World War I, the American chemical industry was primitive. Most chemicals were imported from Europe. The outbreak of war in August 1914 resulted in an immediate shortage of imported chemicals. One of particular importance to Edison was phenol, which was used to make phonograph records—presumably as phenolic resins of the Bakelite type. At the time, phenol came from coal as a by-product of coke oven gases or manufactured gas for gas lighting. Phenol could be nitrated to picric acid and converted to ammonium picrate, a shock resistant high explosive suitable for use in artillery shells. A telling of the phenol story is found in The Aspirin Wars. Most phenol had been imported from Britain, but with war, Parliament blocked