You have a few options for doing cell renders. Best results are going to be gotten by doing a combination of these.
Zygock made a free plugin called YAToon.
Digital Carvers Guild has a paid plugin called Toon Pro. It does work well in combination with the Parchment plugin DCG also makes and with Zygock’s YAToon.
For info on plugins and link to get them see this post.
See the attached image for a YAToon and ToonPro example I dod when I first got the ToonPro. Lighting isn’t good in it.
Age Armor made some free Toon Shaders
Click thumbnail to see full-size image