Within the last decade, laser-plasma based accelerators have been able to deliver electron beams with Maxwellian energy distributions characterized by effective temperatures in the range of 1–20 MeV. Changing the interaction parameters, the electron beam quality was improved. Especially, matching the interaction length to the dephasing length was crucial to produce an extremely high quality electron beam with a quasimonoenergetic distribution at 170 MeV. The optimization of these distributions is presented, as well as comparisons with three-dimensional particle-in-cell code simulations.