#TIL: What are the EV Charging keywords
by Shilpi Samantray
Simply put, an EV charging station is an infrastructure that supplies electrical energy for charging vehicles. Formally called Electric Vehicle Service Equipment (EVSE), it could be a fixture connected directly to an electrical outlet or to an electric distribution panel. At a basic level, a charging station comprises a charging cable that connects the EV charging socket to a battery via a connector (like a gas pump nozzle), and a button for starting or stopping the charging operation. A station may have additional features like energy meter, electronic payment system, card controlled access system, internet access, and more.
The time taken to charge an EV varies due to factors like: size of the battery, state of the battery (empty or full), maximum charging rate of the vehicle (which is the maximum charge rate the vehicle can accept), maximum charging rate of charge point (which is the capacity of the charging plug point), or environmental factors (battery performance during hot weather and cold weather is different!).
Accordingly, different types of EV charging are as follows :
- Slow charging: It is usually associated with home/office/overnight charging. The charging time varies between 4 and 12 hours. With slow charging, the EV battery is connected to the grid for a longer period of time, increasing the possibility of providing flexible services to the power system. The chargers used in slow charging are typically up to 22 KW. Today most chargers installed at public or private premises are slow chargers.
- Fast charging: If the charger charges a battery in one hour, it is referred to as a fast charger. These are likely to be used in direct current (DC) systems, often along highways and street chargers. The chargers used in fast charging are typically 50KW and above. With the increase in power demand, this mode of charging can have an adverse impact on the grid, which in turn can be mitigated by installing charging points integrated with renewable energy sources or in areas that have low peak demand and congestion.
- Ultra-fast charging: If the charger charges a battery in 30 minutes or less, it is referred to as an ultra-fast charger. The chargers used in ultra-fast charging are above 150 KW. This mode of charging is expected to help overcome the range anxiety of customers of electric vehicles. In addition to adversely affecting the grid, fast and ultra-fast charging may also cause battery degradation.
- Battery swapping: Battery Swapping as the name suggests is a charging technique where the battery is charged outside of a vehicle and a fully charged battery can be swapped quickly (less than 3–4 minutes) with a discharged battery. This mode of charging is one of the ways to accelerate the faster adoption of EVs (especially for the 2W and 3W segments). It can mimic the experience of existing fuel pumps, eliminate wait time and can help in balancing the electricity demand load during peak hours.
- Wireless charging: Wireless charging uses an electromagnetic field to transfer electricity to an EV without a cord. A charging pad is connected to a wall socket and a plate is attached to the vehicle, and the system uses electromagnetic waves to charge the battery. It can provide power up to 11 KW.
In India, most of the existing charging stations use slow charging technology while a handful of them use fast charging and battery swapping. As the country focuses on scaling EVs, it is imperative to establish a robust charging network that is easily accessible and convenient, and uses technology that is future-looking and relevant for Indian conditions and use-cases.
Today I learnt (TIL) is a weekly series by OMI that brings you interesting nuggets of information that you didn’t know you needed.
