Electric Vehicles are in themselves a huge market–.the unit sales of the Electric Vehicles (EV) market are anticipated to reach 17.07M vehicle units by 2028. With many EVs bound to circulate, charging them is quite the task. There are three primary methods of EV battery charging: battery swapping stations, conductive charging–wired charging stations, and wireless charging.
Wired EV charging typically requires the driver to plug the vehicle into a charging station using a cable. This method offers high charging efficiency and reliability ensuring a secure connection between the vehicle and the charging point. However, it may require more effort from the driver, especially when manoeuvring the cable and plugging it in. Moreover, involving wires brings forth safety issues.
Specifically, wireless charging allows EV batteries to be charged from a distance without requiring a physical connection. This offers greater convenience and ease of use, as drivers must park their vehicles over the charging pad to initiate charging. Wireless charging also reduces wear and tear on cables and connectors, potentially increasing the longevity of both, the vehicle and the charging infrastructure. The discussion comparing wired and wireless EV charging must include consideration of efficiency and charging speed.
To discuss the latest market trends and insights
This consideration stems from the practicality of charging an electric vehicle efficiently. If wireless charging prolongs the charging duration significantly, users may prioritize wired chargers despite the inconvenience of dealing with cables. Thus, the decision hinges on finding a balance between convenience and charging speed.
Efficiency of Wired EV Charging
When discussing charging efficiency, several factors come into play. In wired EV charging systems, efficiency hinges on cable resistance, voltage and current regulation, charging protocol compatibility, and temperature management to prevent overheating or overcooling of the battery. Achieving a high power factor and seamless grid integration are also crucial for minimizing energy wastage and ensuring reliability. Ultimately, the combined efficiency of the charging station and battery determines the overall effectiveness of EV charging, whether wired or wireless.
Efficiency of the ‘State of The Art’ Wireless EV Charging Methods
While wired EV charging system offers high efficiency and reliability, wireless charging technologies are rapidly advancing to bridge the gap. Three main techniques employed for wireless charging are stationary charging, dynamic or in-motion charging, and quasi-dynamic charging.
Stationary charging involves parking the vehicle over a charging pad, allowing for convenient and efficient charging without physical connections. However, alignment between the transmitter and receiver coils is crucial for optimizing efficiency in stationary charging systems. Current prototypes of stationary inductive charging systems have a broad range of efficiency–80-98% depending on the airgap, core and frequencies employed.
Our brochure and sample reports highlighting the scope and coverage of our research solutions.
The Stationary Capacitive EV charging isn’t lenient with its alignment requirements either albeit the safety and reliability it provides which ultimately leads to similar efficiency numbers–74.7-96%. The hybrid stationary EV charging systems are not expected to be any more efficient either.
Dynamic or in-motion charging, on the other hand, allows vehicles to charge while on the move, offering continuous charging without the need for frequent stops. While dynamic charging has the potential to revolutionize electric transportation, it presents technical challenges related to maintaining efficient power transfer while the vehicle is in motion. The main technology used for dynamic charging is electromagnetic induction, where charging pads embedded in the roadway generate magnetic fields that wirelessly transfer power to receiving coils installed on the vehicle.
Dynamic inductive charging systems for electric vehicles require precise alignment and positioning between the charging infrastructure embedded in the road and the receiver installed on the vehicle. Maintaining optimal alignment while the vehicle is in motion presents a challenge, as deviations can lead to diminished charging efficiency and potential disconnection. This challenge also seeps into In-motion capacitive charging systems which however do have an edge over the former since they allow for a reduction in battery size by approximately 20%, leading to lighter and more cost-effective electric vehicles. The efficiency of the dynamic inductive charging systems is expected to be high.
Quasi-dynamic (opportunity) charging aims to combine the benefits of stationary and dynamic charging by allowing vehicles to charge at specific intervals or locations, such as at traffic lights or designated charging zones. This approach offers improved efficiency compared to dynamic charging while providing flexibility and convenience for electric vehicle owners.
However, amongst the three charging methods mentioned above, the overall choice of employment depends not just on the technical efficiency of the charging method so to speak.
Summary
Overall, both wired and wireless EV charging systems have advantages and disadvantages in terms of efficiency, reliability, and convenience. As technology continues to evolve and infrastructure improves, the efficiency gap between wired and wireless charging narrows. This ultimately provides consumers with more choices and enhances the accessibility and sustainability of electric transportation.
About Wired and Wireless Technologies (WAWT)
Wired and Wireless Technologies (WAWT), through its comprehensive research data and insights and market intelligence on the wireless power market. Its service titled ‘Wireless Power Intelligence Service’, covers various types of wireless power technology solutions using different frequency levels – be it inductive, resonance, NFC, RF, or infrared-based.
For our informative & insightful Newsletter “Power Bulletin”
WAWT monitors the use of different types of wireless power technology solutions developed and adopted across 30+ different types of application markets. It covers automotive, consumer, computing, defence, wearables, hearables, medical/healthcare, smart home, industrial, robotics, retail, infrastructure, and other sectors.
WAWT have dedicated coverage of the automotive sector, covering applications like EVs, e-bikes/e-scooters, and ‘in-vehicle’ wireless charging. Reach out to our subject matter experts (SMEs) by emailing analyst@wawt.tech. Also, follow our LinkedIn page (WAWT) for the latest market trends and updates on wireless power and allied technologies.