Deflating the Hype Around Super-Fast Charging

The race to build ever-quicker EV charging units continues to accelerate. ABB recently unveiled what it calls the world’s fastest electric charger—the Terra 360 has a 360 kW capacity and can theoretically charge an EV in 15 minutes. The charger also has four connectors, enabling four EVs to charge simultaneously. Sales will begin in late 2021 in Europe, with expansion to North America and other regions in 2022. While the Terra 360 has impressive power capabilities, charging at these levels is not yet realistic or even ideal for most EVs on the road.

Fast Charging Is Not Yet Practical

Several key realities about the EV market make fast charging announcements from ABB, Tritium, and others less compelling than they appear:

• Few EVs have the capacity to utilize a 350 kW plus charge. The two vehicles that come close have yet to make a dent in total EV sales. The Porsche Taycan has a charging capacity of 270 kW, and has sold less than 5,000 units in the US in 2020. The upcoming Lucid Air has 300 kW of charging capacity and is only available for reservations, but deliveries have not yet begun. By far the two best-selling EVs in the US, Tesla’s Model 3 and Model Y are well short of being able to use a 360 kW charge with each having 250 kW of charging capacity.
  
• Real-world charging rates are considerably slower than peak capacity. According to the Dutch EV charging operator Fastned, even at peak speed a 300 kW charger does not reach 200 kW when charging a Tesla Model 3. Charging rates are improved slightly on Tesla Superchargers; Car and Driver found that a Tesla Model 3 Long Range reached a peak of 201 kW on a 250 kW Supercharger.
  
• Fast charging increases EV battery degradation. It is well accepted in the EV industry that fast charging generally increases the rate at which an EV’s battery capacity will decline. Porsche, for example, offers a battery preservation setting on the Taycan, which lowers power consumption from the 270 kW maximum to 200 kW to preserve battery life.
  
• Over 150 kW charging minimally reduces overall charge times. Car and Driver tested charging a 2019 Tesla Model 3 on both a 250 kW Supercharger and a 150 kW charger. The higher power 250 kW system only saved 2 minutes in total compared to the 150 kW model (both scenarios charged from 3%-100% battery). As the figure below shows, the 250 kW charger mostly outperforms the lower power charger in the first 10%-35% of charging. After these initial stages, the two chargers follow similar charge rate paths as the battery level increases.
  

Car and Driver 250 kW and 150 kW Supercharging Test Results: Tesla Model 3

(Source: Car and Driver)

Although a leap is required in charging replenishment speeds and strategies for EVs to truly become mainstream, many of the recent fast charging announcements are misleading in terms of real-world practicality and performance and are bound to leave many consumers disappointed. Over-hyping fast charging technologies could also potentially be counterproductive by distracting from other promising solutions such as battery swapping.

The practical impact of ABB and others’ fast charge announcements is likely best realized by fleets where commercial vehicles have larger batteries better able to absorb higher capacity charging. Another advantage for fleets and super-fast charging is that fleet depots have spatial engineering challenges that can be partially addressed by the power sharing component of ABB’s charger. Pertaining to the consumer market, EV drivers should not expect a significant boost in charging time—that must wait for better EV batteries and 800 V architectures.