Level 3 DC fast charging to power EVs in under 15 minutes, IDTechEx reports
According to IDTechEx, high power chargers (HPCs), or those that provide Level 3 DC fast charging at a rate of 50 kW or more, the time to recharge light-duty electric vehicles is expected to drop to below about 15 minutes to charge to 80%, which is closer to how long it would take to fill up a conventional diesel or gas-powered vehicle. This would improve overall utilization of a commercial fleet, as thety could spend more time working and less sequestered to a charging station.
This is due to increasing vehicle range and battery capacities and an increased ability for vehicles to accept higher charge rates. IDTechEx forecasted this projection off of a variety of industry announcements, using variants of current battery chemistries and battery pack designs. A new report by IDTechEx called “Charging Infrastructure for Electric Vehicles and Fleets 2022-2032” goes deeper into the costs and necessary footprint to accommodate HPCs.
As their batteries are the largest, the Class 8 truck market will likely need the most innovation to appear to reach this 15-minute milestone. Currently, fleets report charging a Volvo VNR Electric truck to 80% with Level 3 fast charging takes 70 minutes.
IDTechEx also noted more vehicle models will be designed to accept the higher electrical output from HPCs in the next several years, though over the next few years, existing low-range electric vehicles will not be able to take advantage of chargers operating at 350 kW. These EVs will rely on a mix of charging speeds available at charging sites.
IDTechEx said that by "controlling power output at a single charger, or sharing power among a group of chargers, will usually satisfy the mix of vehicles that arrive with the ability to charge at their maximum power acceptance rate."
HPCs will come with higher hardware and utility costs than Level 1 or Level 2 charging in most settings.
Infrastructure upgrades will include new distribution lines and the final transformers, along with the installation of separate power cabinets to the charge posts. IDTechEx advised several strategies to mitigate these, including:
- Choosing locations with low grid impacts
- Smart charging
- Combining fast charging with energy storage
- Applying time-of-use rates
The market research firm noted that HPCs are modular and available in 50/75 kW step power units, which are connected to meet the required power demand, and can scale up or down based on utilization.
More considerations
Sending too much power to the battery during charging may cause lithium plating and dendrite formation around the anode, which would permanently reduce capacity. At the pack level, this can cause irregular rates of cell aging at different rates and could create overheating. To compensate, HPCs require cooling technology to ensure optimal performance at high-efficiency levels. Solutions include preheating batteries, liquid cooling, and using intelligent battery and charger-management software.
A lack of standardization exists among DC fast charging plugs, with five options that transmit above 36 kW:
- CHAdeMO
- U.S. Combined Charging System (CCS type 1)
- European Combined Charging System (CCS type 2)
- Tesla
- GB/T (used in China)
According to IDTechEx, CHAdeMO plugs support 1000 V and 400 A and enable a maximum power of 400 kW. Meanwhile, CCS type plugs now support a maximum voltage of 1000 V at 500 A, and they enable a maximum power of 500 kW. The CHAdeMO does not exceed 150 kW, making CCS the preferred connector type for HPCs that offer a 150 kW-350 kW range power range.
Tesla's incrementally increasing V3 supercharger can now deliver 250 kW of peak power. In China, the ChaoJi protocol was enacted to achieve harmonization between GB/T and CHAdeMO standards. A target of 900 kW has been set to allow for the charging of large commercial vehicles such as buses and trucks.
Also of note, the nonprofit CharIn association has developed the High Power Charging for Commercial Vehicles (HPCCV) standard, which will be used for charging in the range of 200 V-1500 V and 0-3000 A enabling up to 4.5 MW of power delivery. The group noted there are 46,000 CCS charging points globally, with 29,000 in Europe, 13,000 in Asia and the Pacific, and nearly 5,000 in North America.
