Tata Motors has already launched Tigor EV with a range of 142kms and it takes 6 hours to charge from 0 to 80 percent via a normal charger. Earlier it was for commercial use only but now one can register for personal use too. Moreover, we would suggest you to test drive the vehicle in order to check the performance and comfort. You can click on the following link to see the details of the nearest dealership and selecting your city accordingly - Car Showrooms.
It would not be possible to install an additional battery in order to extend the range of the Tata Tigor EV. The Tigor EV now uses a 21.5kWh powertrain that drives a 72V 3-phase AC induction motor. According to ARAI, the Tigor EV has a range of 213km compared to the 142km before. The increased range of the Tigor EV is due to the 21.5kWh battery pack, compared to the 16.2kWh battery pack offered before.