Some of the more interesting DC motors use masses of electronics (eg the so-called "Switched Reluctance (SR) Drive) to improve efficiency, but possibly making them difficult to get certified for aircraft use.
I wasn't thinking of the common induction motors which are indeed everywhere and have been for ~ 90 years. I was thinking of 3-phase brushless motors which are controlled from electronic drives, which take in either DC, or AC mains power. These motors are big versions of the 3-phase brushless motors used in model planes, boats, etc. Industry is full of them - conveyor belts, cranes, you name it. One customer of mine has a production line chucking out a motor controller every 10 or 20 seconds, and each of these will be used with a 3-phase brushless motor, with an iron core. There are some fancier designs but they go into less common applications. For an aircraft you would have just a dead simple 3-phase brushless motor driven from a controller using IGBTs or some such.
The technology for this is several decades old and anybody could take an existing plane (my TB20 would do just fine) and stick a 250HP direct drive brushless motor in there (a suitably ruggedised version with a massive shaft and bearings because it has to carry the prop and the axial loads) and an off the shelf variable speed controller, plus a lump of concrete for W&B reasons because the assembly will be so much lighter than the old engine, and ..... sit there and stare at it because it won't be going anywhere
The battery, and how to charge it in practice, will be the major issues.
It goes without saying that certification would be a major project, regardless of what motor is used. The motor will be the easy bit. Demonstrating safety of the battery would be something else. All you need is a defect within the battery, or a short downstream, and you have a massive fire - unless the battery technology is very different to the present LIPO ones.