He studied zoology and comparative anatomy at the University of Leipzig, where under the influence of Carl Chun (1852–1914), he focused his energies towards research of marine fauna, especially cuttlefish.
[1] After graduation, he worked as an assistant at the Leipzig Zoo, being tasked with scientific design issues concerning its aquarium and terrarium.
[1] He is the taxonomic authority of numerous taxa, including the cephalopod order Vampyromorpha and the families Stauroteuthidae and Chtenopterygidae.
[2][3][4] In 1933 Grimpe signed the Vow of allegiance of the Professors of the German Universities and High-Schools to Adolf Hitler and the National Socialistic State.
With ichthyologist Erich Wagler (1884–1951), he collaborated on a textbook of marine biology titled "Die Tierwelt der Nord- und Ostsee" (Fauna of the North and Baltic Seas), and beginning in 1927, he was editor of the journal "Der Zoologische Garten".