Indian Committee on standardization for EV Charging infrastructure has defined protocols for AC and DC charging of electric vehicles. These are specified as Bharat EV Charger AC-001 and Bharat EV Charger DC-001. An insight into the nomenclature and fundamental knowledge of EV charging infrastructure is discussed in this article.
Charging types and overview of connectors
AC Charging is the most common basic type of EV charging where simply plugging with the ac socket, can charge your vehicle. It requires 5-amp (type D) or 15-amp (type M) inlet connectors in India. As per Bharat EV specifications, most electric vehicles are charged directly using the IEC 60309 and IEC 62196 Type 2 connectors with cable type B for AC type charging. Most of the Indian e-scooters use simple 15-amp 3-pin connectors. This type of charging is categorized into the following types:
- Slow AC Charging:
Under this category, 2-4 kW chargers are available for 2 & 3 wheelers and 4-wheelers or higher vehicles charging in 1-2 hours and 6-8 hours respectively.
- Moderate/Fast AC Charging
A typical EV charger of a 7-25Kw power rating falls under the category. Normally, 4-wheelers electric vehicles are limited to 4 kW chargers. Charging rates may vary depending upon the EVSE charging rate and the vehicle model.
DC Charging bypasses the onboard charger and directly charges the battery. It is the premium option of faster charging. As per Bharat Specifications, India is available with DC Level 1&2 fast chargers that provide output power as 10-15 Kw and 30-50Kw respectively. Globally as well as nationwide, there are four types of DC inlet connectors namely CHAdeMO, SAE Combo Charging System (CCS), Tesla standard Supercharger, and Chinese standard GB/T connector.
This type of charging option is a super-benefactor for the e-fleet services or heavy-duty and medium-duty vehicles and buses which typically require a reasonable recharge time for their larger batteries. Such charging stations are established in public places and are owned by the charging network operators and provide services to the EV OEMs.
Indian EV Charging scenarios
- Public Charging:
A wall-mounted charging connector on EVSE provides a higher rate of charging up to 7 kW of (ac) charging power. Every electric vehicle is equipped with an onboard charger that converts your ac socket supply to dc supply for charging your battery. A public station is a common port connected at any retail shop on corridors/highways, curbsides, malls, or in joint with regular diesel/petrol pump stations. It can provide an option of dc (it is expected in India up to 50KW) or ac charging inlet ports which can vary in charging time from 25-30 mins to 8 hours of full charge depending upon your vehicle type.
- Home Charging:
Unlike traditional vehicles where fuel filling is only satisfied at the petrol or CNG station, an electric vehicle has the advantage of home charging over public station charging. For this, an OEM suggested charging utility is the only requirement. Normally, home charging is available with an option of ac charging with a 15Kw power charger which takes 8-10 hours of charging time, but nowadays dc home charging is entering the houses worldwide and yet to come in India.
- Battery Swapping:
Battery swapping is the most recent alternative to charging technology across the globe. Many Indian start-ups and companies have collaborated with the giants and are coming up with swapping stations across the nation. The primary focus of the battery swapping technology is for 2 & 3-wheeler EV segments.
Different EV segments and their corresponding charging ratings are given below:
Apart from a suitable type of EV charging, reliable communication between EVSE and vehicle is another vital requirement. A well-defined EV charging fundament has always been a key for the adoption of electric vehicles in the nation. There are many policies and strategies are being established to incorporate a dedicated charger in the EV ecosystem.