Hi Siva, this is definitely an interesting application.
Simscape Electronics and Simscape PowerSystems have several blocks and components that can help you model a battery electric vehicle charger.
As you mentioned, a three phase rectifier can be a good starting point. Check the link below which takes you to an example of how to model an Automotive Alternator - although this is not the exact same thing as a high voltage battery charger, it is still a good baseline for modeling charging operation of a battery in a vehicle. You may have to change some parameters to match your HV system. Depending on the level of fidelity you want, you may even need to add other blocks like the 'Chopper' found in PowerSystems >> Specialized Technology >> Electric Drives >> Fundamental Drive Blocks.
Just be aware that simscape works by domains (electrical, mechanical, specialized technology), and you may not always be able to interface these domains with each other. However, there are some blocks that allow you to interface multiple domains, for instance, the Three Phase Rectifier block lets you interface thermal, mechanical, and electrical domains together. Similarly, there are some other blocks that let you combine power systems domain with electrical domain blocks.
I am sure this example will be helpful to get you started with modeling BEV chargers: