Presence of electron trap states in conjugated semiconducting polymers strongly lowers the performance of devices like polymer light emitting diodes (PLEDs) and organic photovoltaics (OPVs). A major loss process in PLEDs is the recombination of trapped electrons with free holes, which is a non-radiative process. In this study the electron- and hole transport as well as recombination is studied in PLEDs based on blends of the poly(p-phenylene vinylene) derivative MEH-PPV with the wide band gap polyfluorene derivative PFO. Surprisingly, the electron transport in the MEH-PPV phase is strongly enhanced with increasing amount of PFO. Analysis reveals that addition of PFO deactivates the electron traps in the MEH-PPV phase of the blend. For a MEH-PPV:PFO ratio of 10:90 the electron transport in the MEH-PPV phase is fully trap-free and identical to the hole transport. As a result we were able to fabricate for the first time PLEDs with balanced electron and hole transport. In these blend PLEDs loss processes like quenching of excitons at the cathode due to unbalanced transport as well as the non-radiative trap-assisted recombination are strongly reduced. This was independently verified by measuring the light intensity dependence of the open-circuit voltage of the blend PLEDs. Due to the reduction of the loss processes the efficiency of these blend PLEDs is doubled as compared to a standard MEH-PPV PLED.