Thanks for your post, Shishir. It's possible to give vehicles a custom nickname by navigating to Settings > Your Vehicle Profile, but this nickname only appears in the app at this time (it doesn't appear on the web dashboard).
I'm going to change your post from a "Question" to an "Idea" so we can keep track of the request for nicknames to appear in the web dashboard. Thanks for the idea!
Here's a screenshot of where you can assign your vehicle a custom nickname (iOS):
Sound good Tom. It is indeed an idea and not a question. I was able to nickname my cars on mobile device but it would be useful to have the same feature (of nick nameing each car) on web dashboard as well. I use web dashboard more than mobile app. Thanks.