The e-mobility industry has made remarkable advances in electric vehicle (EV) technology and the rollout of charging infrastructure. However, for EVs to become the norm rather than the exception, the charging process at public chargers needs further improvement to deliver a seamless, safe, and secure user experience (UX).
Imagine a world where you could charge your EV as quickly and easily as you can fill up a gas tank. That's the future of EV charging that is being envisioned by engineers and entrepreneurs around the world. But achieving this vision will require significant progress in the area of EV charging to improve the UX. Today's EV charging stations can be slow, inconvenient, and even unsafe. But new technologies and innovations are emerging that promise to revolutionize the way we charge our EVs.
Advancement for seamless experience
To achieve this, new technologies are emerging that aim to further alleviate user concerns surrounding the range and time-to-charge an EV. These advances also seek to play a significant role in transitioning the EV charging UX toward the convenient refueling process consumers have grown accustomed to when filling an ICE vehicle’s fuel tank.
However, key to a positive user experience is the time spent at the charging station. The goal being to reduce EV charging times to compete with a conventional fuel fill-up.
This in turn requires high-powered public DC fast charging stations having more than 50 kW of charging power, operating at 400 or 800-volts - and in future, even higher.
While this high-power charging (HPC) can significantly reduce charging times, it is important that EV charging-system designers plan for safety and security at the outset, ensuring the welfare of the user at all times.
Even though high power EV charging stations do come with inherent risks and hazards, designers and installers adhere to rigorous design safety-standards and operating procedures to ensure the safety of all operators, at all times.
Safety is paramount
Until the advent of DC charging, the public did not have access to power higher than that delivered by a 120 V home wall socket. Now, with high-powered EV fast-chargers operating at 400 to 1,000 V capable of delivering upward of 350 kW, designers have to minimize safety concerns while ensuring long-term reliability under all operating conditions.
This includes making sure that, even though, because of their location they are easily vandalized, stations damaged because of tampering will be safe to operate or automatically shut down.
By their nature, DC fast-charging stations require an electrical connection capable of delivering high power. In these situations, electrical faults, including those that initiate ground faults, can be very destructive - in extreme cases, damaging critical components and exposing bystanders to injury.
While safety labeling is a great way of warning users of the potential risks of improperly handling the equipment, it is nevertheless important that designers and installers of these high voltage chargers consider the user’s safety at all times.
Mitigating electrical shock
One of the largest safety threats in an EV charging station is the risk of a user receiving an electrical shock.
Electrical shock is typically the result of a ground fault, usually an unintended contact between an energized conductor and ground or the equipment frame. This is often the result of a breakdown in insulation or dust and moisture creating unintended pathways for electricity flow.
Wet and dusty environments, such as often encountered at outdoor public charging stations, require designers to consciously design-in safety, with operators conducting frequent maintenance of the equipment to ensure safe operation at all times.
With commercial high-powered EV charging station installations constructed with safety in mind, AC ground-fault protection is installed on the input side of the charger. This not only protects components from destructive faults, but protects consumers from electric shock should the charger’s frame or housing become energized.
Similarly, ground-fault protection is required on the output side to ensure that, when an operator picks up a nozzle capable of 1,000 V, the handle or the frame is not energized. A DC ground-fault monitor is typically installed on the output side to detect any earth leakage and shut off power immediately.
As an additional safety measure, manual emergency shut-off switches are also fitted to all charge points that stop energy flow directly in an emergency.
Connectivity drives efficiency but raises cybersecurity concerns
At the same time, power conversion is crucial for efficient DC fast charging. Minimizing losses in power conversion optimizes power delivery for charging the vehicle’s battery while reducing heat buildup.
What is more, utilizing vehicle and infrastructure connectivity it is possible to monitor and manage the charging event in real-time, thereby enabling the station to adjust its charging parameters to make overheating less likely, ultimately making for a safer UX.
However, this connectivity also introduces a cybersecurity risk that needs to be managed.
To win the user’s trust in charging at public charging stations, operators need to implement processes to combat hacking and other cyber-attacks that could compromise the integrity of the charging station, making it less safe.
User privacy and UN regulations
EV chargers present several significant attack surfaces for hackers to exploit. Unlike ICE refueling, when people plug their EVs into charging stations, it is not just power flowing through the cables. The charging stations communicate directly with the vehicle, transmitting all sorts of data – from charge-rate to payment, and location tracking.
So, by installing malicious software at public charging stations attackers could theoretically gain access to the car’s ID, payment details, even how much battery power is left.
In extreme situations, they could use the connection between the charging station and the car as an entry point to access the car’s internal Controller Area Network (CAN) bus. This could give an individual with ill intent the opportunity to manipulate critical operating systems, endangering both the vehicle and the driver.
Incorporating threat detection and monitoring tools into EV charging infrastructure could limit many of the risks associated with the technology.
Key to managing the ever-evolving cybersecurity threat are regular security patches delivered over the air (OTA).
However, this in itself requires robust security measures to safeguard the entire OTA update process. These include secure communication channels, encryption, and authentication mechanisms to prevent unauthorized access and tampering.
For organizations, using strong authentication mechanisms for accessing EV systems and data will help prevent unauthorized access. Similarly, EV owners should use strong and unique passwords for EV-related applications and accounts, as well as enabling two-factor authentication where possible.
Over and above the functional security of the charging eco-system, user’s information, privacy, and confidentiality has to also be protected when establishing connections between cars and charging stations.
The importance of protecting confidentiality has been highlighted as a key guideline by the UN Regulation No. 155 on cybersecurity.
This compliments the standard IEC 61851-1 (IEC 2017) that defines general and safety requirements for electric vehicle supply equipment (EVSE), but does not specifically define any functional safety requirements in case the safety-related functions in the charging station are implemented through programmable electronic systems.
The scope of the updated IEC 61851-23 standard, was expanded to cover every aspect of the charging equipment, including the design of the charging cables, which must comply with HD 60364-5-52. This also includes the testing of the temperature during one hour of continuous operation.
Conclusion
The EV charging user experience is a critical factor in the widespread adoption of electric vehicles. If EV charging is not safe, secure, and convenient, people will be less likely to switch to EVs.
It is therefore imperative for all stakeholders in the EV-charging ecosystem - from manufacturers to infrastructure providers, policymakers, and consumers - to remain actively engaged in advancing this cause. By doing so, we can ensure that EVs offer a user experience that seamlessly integrates into our daily lives, thereby accelerating the rollout of e-mobility.
