Lew Urry developed the small alkaline battery in 1949 using a version of the alkaline battery that�. Thomas Edison invented in 1901 and set out to make it more practical for everyday use. Urry was working for the Eveready Battery Co in the USA at the time.
Duracell manufacture alkaline batteries under their own tradename.
I imagine that you are looking for Thomas Edison, though there are some who believe that batteries were developed as far back as 300BC.