Rapid Strides: Technology trends shaping EV charging infrastructure

The global electric vehicle (EV) char­ging market is poised for significant growth, anticipated to reach $30.4 billion by 2023 and $35 billion by 2026. The future of EV charging infrastructure holds abundant prospects, with the em­ergence of innovative next-gen vehicles and complementary components anticipated in the coming years.

Several new technologies are being de­veloped in the EV charging space, wi­th the expectation of transforming the sector, enhancing efficiency and driving inc­reased EV uptake.

Charging EVs encompasses a range of methods, contingent upon factors such as location and specific needs. As a re­sult, EV charging infrastructure comes in various types, each designed to suit par­ticular use cases. The specifications and standards for EV chargers, also known as electric vehicle supply equipment (EVSE), differ from country to co­untry. These distinctions are influenced by the variety of EV models available in the market and the unique characteristics of the local electricity grid.

The fundamental component of EV charging infrastructure is the EVSE. This unit taps into the nearby electricity so­urce, employing a control mechanism and physical connection to effectively charge EVs in a secure manner. The control system integrated into the EVSE facilitates multiple operations such as user validation, permission for charging, data logging and sharing for network administration, as well as ensuring data privacy and security.

EVSEs vary in power ratings, determining the required input power for charging infrastructure. Standard AC charging is suitable for e-2Ws, e-3Ws and e-cars. Unique to India, normal power DC char­ging serves low-emission vehicles (LEVs) and low voltage e-cars. Single-phase AC (up to 7 kW) is sufficient for LEVs and single-phase e-car chargers, while larger e-cars require three-phase AC (up to 22 kW). Normal power supply from the grid suffices for these cases. High voltage e-cars (30-80 kWh) utilise 50 kW high-power DC charging, currently available up to 60 kW, with higher power options expected. While high-power DC offers faster speeds, it demands more electricity and infrastructure. Normal power ch­arging is suitable for most needs, including overnight e-car charging.

Battery charging methods

Automobile manufacturers are exploring innovative methods of charging EVs with the objective of establishing an ef­fective and elaborate EV charging in­frastructure,

Batteries can be charged in various wa­ys. Conductive charging, commonly kn­own as plug-in or wired charging, stands as the prevailing technology for recharging EVs. The specifications for EVSE in conductive charging are contingent up­on variables such as vehicle category, battery size, charging techniques and po­w­er levels.

EVs equipped with in-motion (dynamic) wireless charging have emerged as a po­tential solution to enable longer service hours, smaller battery packs and en­han­ce autonomous capabilities. Wire­less charging systems can either be stationary, which means that they can only be utilised when the car is parked or in stationary mode, such as in car pa­­r­ks, ga­rages, or at traffic signals; or th­ey can be dynamic.

Meanwhile, bidirectional charging is an­other emerging charging technology and involves channelling energy from vehic­les to various sources such as loads (V2L), other vehicles (V2V), homes (V2H) or the grid (V2G), standardised in ISO 15118-20. Infrequent drivers utilise only a fraction of their EV battery capacity, leaving pot­ential for storing unused PV power or rapidly charging needy EVs. Shi­fting electricity use based on variable tariffs can cut costs and support grid stability, while a network of connected EVs could potentially transfer power back to the grid.

EV charging companies and third-party players are providing software solutions to enhance the end-user experience. Such network management software de­tects the location of different EV charge­rs, generates billing for the charging and provides detailed reports and analytics of charging trends, costs, and even gre­enhouse gas reductions. Some chargers provide V2G support as well.

Charging standards

Standards guarantee that all EVSEs are compatible and can work seamlessly with any EV model. In India, the Bureau of Indian Standards (BIS), the national standards organisation, formulates the country’s EV charging standards. BIS is aligned with the International Electro­technical Commis­sion (IEC), a global entity that develops reference standards to enhance EV interoperability and ease trade barriers.

IS 17017 is India’s primary EV charging standard, divided into three parts and six sections. IS 17017 Part 1 outlines the fundamental features of all EV charging systems. The standard is focused on the general requirements, characteristics, operations and communication connection between EV and EVSE for a conductive EV charging system. It is appli­ca­ble for EV systems with supply voltages of up to 1,000 V AC or 1,500 V DC and output voltages of up to 1,000 V AC and 1,500 V DC.

IS 17017 Part 2, Section 1 covers the ge­ne­ral requirement of plugs, sockets, ve­hicle connectors, and inlets for conductive charging. The standard applies to a system rating of up to 690 V AC at a rated current of 250 A, as well as 1,500 V DC at a rated current of 200 A8.  It covers de­tails such as wiring, terminals, ratings and the connection between the power supply and the EV.

IS 17017 Part 21 standardises the electromagnetic compatibility of EV chargers and provides electromagnetic compatibility of onboard EVSE.

Both AC and DC EVSEs are required to meet the technical standards outlined in IS 17017 Parts 21 and 22. Additional In­dian standards are in place for affordable AC EVSEs suitable for light EVs and e-cars, designed for parking areas.

In April 2023, BIS introduced standards and tests for EV charging infrastructure, as well as criteria for battery swapping sy­stems, including safety standards for such systems. The series consists of 10 parts that define charging modes, communication protocols, electrical safety and performance test requirements for EV charging systems.

Another crucial aspect that requires attention from all charging point operators and original equipment manufacturers is interoperability. Cooperation bet­ween them is essential for managing asset utilisation and capex related to land, power connection and upgradati­on of transformers at the distribution level. Recently, the Bharat Charge Allia­nce and CHAdeMO Association collaborated to develop interoperable charging infrastructure. The specifications for building this infrastructure will be alig­ned with IS/IEC standards. The Alliance intends to implement standards publi­s­hed by BIS, including IS 17017: 25 (based on IEC 61851-25) EVSE standard and IS17017-2-6 (IEC 62196-6) for vehicle inlet and connector.

EV charging technology innovations

A key technology focus area in the EV charging market is fast charging. Fast chargers are beginning to pop up in ci­ties and are a prerequisite for public and on-street charging to minimise waiting time. Currently, the available commercially fea­sible EV batteries require app­roxi­ma­tely 10 hours for a complete ho­me re­ch­ar­ge, while the fastest superchargers available today demand 20 to 40 minutes to achieve a full recharge. Emerging ad­vancements such as 800 V charging and quantum charging, which expedite ba­ttery charging, are anticipated to re­shape the landscape of EV charging.

The majority of EVs currently operate on 400 V batteries. However, experts predict that new EV models after 2025 will adopt an 800 V framework. This transition is driven by advanced higher voltage technologies, enabling rapid-charging batteries by directing more current to cells due to increased voltage and the same resistance. Co­up­led with swift-charging batteries, 800 V charging systems theoretically provide 10-80 per cent charge within 10 minutes. In the near future, public EV charging must also achieve “ultra-high-speed” le­vels, addressing key adoption hurdles such as range and charging concerns. Glo­bally, manufacturers are developing stable lithium-ion and solid-state batteries for faster charging, potentially with­in 20 minutes or less. Despite technological strides, the practicality of co­m­mercialising ultra-fast charging remai­ns uncertain due to grid demands and existing challenges.

Net, net, rapid advancements in battery technologies and charging methods will be crucial in achieving the required pace of transition towards cleaner mobility.