Safety might not be the first consideration when selecting a charging station, but safety is actually the most important thing to consider. The primary function of the best EV charging stations is to provide electrical safety for the operator and electrical infrastructure throughout the charging process and specifically to address the risks of fire and electric shock.

The good news is, charging an electric vehicle is actually very safe and easy when done with proper, independently safety-certified equipment. The challenge is that NOT ALL charging stations on the market are independently safety tested and certified.

When a charging station manufacturer develops a new product or makes even a minor change to an existing product, they should send samples to a Nationally Recognized Testing Laboratory. Safety engineers at these labs perform months of extensive safety testing that the products must pass before they can be safety certified and made available to the public for sale.  EVSE (Electric Vehicle Supply Equipment) manufacturers invest heavily in this third-party safety testing. The laboratory safety engineers test the products against thousands of applicable electrical codes and safety standards.

 

AC Charging Stations

An AC charging station is used to transfer AC power from the grid into an EV. Once transferred, the vehicle’s onboard charger converts the AC power into DC power to charge the battery. Due to EV space and weight constraints, onboard chargers and AC charging stations are typically limited to lower amounts of power (22 kW or less), resulting in slower charging times (read more). Though the actual “battery charger” is on the vehicle, a charging station implements several layers of redundant safety features to protect the user from potential electrical and fire hazards while connecting, disconnecting, and charging the vehicle. Once connected to the vehicle, the station informs the vehicle that power is available and at what level. The vehicle then takes over, initiates, and takes full control of the power transfer. If an electrical fault occurs the station will stop the power transfer immediately and de-energize the cable.

Also, certified stations protect the system from overloads. Fast charging is often used to arrange night charging hubs, thus solving 2 problems at once: load distribution on the electrical system (due to charging at night, which avoids the network peak load time), and night parking with a charger, which is extremely important, especially in the case with an electric car.

GO TO-U uses AC stations KEBA (Austria). These chargers have all the necessary European quality certificates, meet safety standards, have a manufacturer's warranty of 2 years, are equipped with a system of protection against incorrect connection, energy leakage sensors, are certified by Renault and Nissan), exclusively recommended by Mercedes and Smart, used by Volvo, Tesla, and BMW.

 

DC Charging Stations

If we emphasize the importance of AC charging safety (up to 22 kW), then with high-speed stations this factor can be multiplied by 10! It's quite simple: the power of a fast-charging station can reach up to 350 kW. Obviously, the requirements for the materials of which these stations are made, and hence for the safety level, must be significantly higher. A reliable and high-quality DC station should not only deliver the proper charging speed but also guarantee protection against damage to both the car battery and the car itself. The fast chargers that GO TO-U works with have an integrated communication protocol with the car, which means that the station not only monitors the charging power and speed but also can detect technical problems of the car and notify about it to avoid danger (eg, battery failure, electric shock, power leakage, etc.).

GO TO-U also provides users with a unique opportunity - a VIP connector. This feature allows you to use the full power of the DC charging station even if it has two high-speed ports. It's quite simple: if the user has booked a VIP connector (regardless of which DC connector he needs), then no one will be able to use the second DC connector at this time (which normally would be available to another user, and the maximum power would be distributed between these two connectors). Thus, drivers can charge their EVs, focusing on the maximum power indicated at the charging station (obviously, if it corresponds to the capacity of the car - read more here).

 

An essential remark! If you have access to AC and DC charging and need to charge the car 100%, then it is better to follow this scheme: charge the battery up to 80% from the DC connector, and the remaining 20% ​​- from the AC connector. This will significantly increase the EV battery life. Thanks to the TO-U application, you can efficiently plan the charging time and book the nearest station with AC and DC connectors for the right time.

 

Difference between 400 Volt and 800 Volt battery architecture

Any charging infrastructure must be tailored to typical user behavior during long trips and offer an appropriate ratio of driving time to rest stops. During a typical break of 15 to 20 minutes, drivers expect to be able to charge an EV battery for roughly 400 kilometers.

There are multiple challenges in significantly reducing the charging time, not least of all being the voltage at which the current generation of EVs charge.

The powertrain and various auxiliary components of the electric vehicle are powered by a high-voltage battery, which is usually located at the bottom of the electric vehicle. Most existing EVs use battery configurations in the 150-450 V DC voltage range, often referred to as the "400 V system". In the electrified trucks and construction vehicles, the maximum DC voltage can reach 870 V - "800 V system".

There are currently few electric models that use an 800 V battery system, including Porsche Taycan, Audi e-tron, Hyundai Ioniq 5.

One of the 800V system advantages is the ability to get more power in kW with less current. Consider the charging of two systems on the example of a Kostad high-speed station.

To obtain a power of 120 kW with a 400V system, we need a current of 300A (300A*400V=120,000 Watts, or 120 kW). This voltage requires special cables that can withstand such a current, which naturally increases the cost of a high-speed charging station. Such cables are bulky and water cooling is usually installed at this voltage.

For a power of 120 kW with an 800V system, only 150A will be enough (150A*800V=120,000W, or 120 kW). Therefore, in this case, it is much easier to ensure parallel charging of more cars with less voltage.

The second and most important advantage of the 800V system is to save money on charging equipment, which makes it possible to increase the number of charging stations.

Currently, most charging station manufacturers only support 400V battery charging systems. In terms of price-quality-functionality, the leader is Kostad - the Austrian manufacturer of high-speed charging stations.

For example, the CPC 120, CPC 150, CPC 180, and CPC 300 are suitable for use in public places (malls, supermarkets, parking lots, and gas stations). The Kostad charging station allows you to charge cars at 400 V and 800 V. GO TO-U is the official importer and distributor of the entire line of Kostad charging stations. These charging stations work perfectly with software from GO TO-U (see more).

 

About GO TO-U

From the very beginning of the EV charging infrastructure development, the main focus for GO TO-U has been equipment safety and reliability. Initially, cooperation with charging station manufacturers was built around these values, and now the platform itself is being successfully developed. On the map of the TO-U mobile application, you will find exclusively safe EV charging stations - more than 300,000 worldwide already. We are approached by businesses from all over the world for advice on the selection and installation of reliable equipment, connection of a smart charging process control system, and monitoring of safety indicators during the charging station usage. Reliable equipment cannot be cheap, as it is made of high-quality materials and undergoes multiple production stages: from design to inspection and certification by the relevant authorities. Therefore, when choosing charging stations for home or business, you should pay special attention to these aspects and understand that the life and safety of the EV driver (as well as the car itself) directly depends on the charging equipment quality.

If you need a detailed consultation on the best EV charging stations - contact us, and we will answer all your questions!

 

Sources: chargedevs

Jun 18, 2021
Latest news
JOIN OUR COMMUNITY
Subscribe for newsletter