EV DC charging: the SiC revolution

This market holds long-term viability due to the continual expansion of charging infrastructure and the coming need for infrastructure replacements. AC chargers will persist alongside OBCs in vehicles until DC infrastructure becomes universally established, a process anticipated to take 10-15 years, announces Yole Group in its DC Charging for Automotive report, 2024 edition.

The total EV DC charging system market will soar to $23 billion by 2029. While chargers between 50 and 150 kW dominated the market in 2023, there is a noticeable surge in demand for higher-power chargers, particularly those exceeding 150 kW. By 2029, the highest market value, estimated at $9.2 billion, will be attributed to very high-power chargers (150 kW ≤ x ≤ 350 kW).

Milan Rosina, PhD., Principal Analyst, Power Electronics & Battery at Yole Group, commented: “The integration of 1,000 V chargers is expected. The objective is clearly to simplify the charging experience for EV owners, irrespective of their battery pack voltage (400V or 800V), thereby streamlining the process of ‘plug and go.’ At Yole Group, we think this advancement will alleviate concerns for OEMs with EVs utilising 800 V battery systems. Indeed, it will eliminate the need to adapt batteries to 500V chargers. Ultimately, this technological shift promises reductions in volume, weight, and cost at the vehicle level.”

Hassan Cheaito, PhD., Technology & Market Analyst, Power Electronics at Yole Group, added: “The primary trends observed in EV DC chargers involve two key advancements: the increase in maximum charger voltage from 500 to 1,000V to accommodate both 400V and 800V batteries and an escalation in power levels to above 350kW for exceedingly rapid charging. However, chargers with nominal power exceeding 350 kW exceed the current charging capabilities of most electric vehicles.”

“These ultra-fast chargers are increasingly engineered to charge multiple vehicles concurrently through dynamic power allocation features. Bidirectional chargers are not anticipated to become mainstream until V2G technology gains traction,” says Yu Yang, PhD., Principal Analyst, Automotive Semiconductors.

Silicon transistors, specifically discrete IGBTs and MOSFETs, remain prevalent in EV DC chargers. The adoption of SiC MOSFET devices is driven by factors such as a smaller charger footprint, enhanced thermal capabilities (resulting in simpler and more cost-effective cooling systems), and a higher breakdown voltage of 1,200 V. The collective impact of these parameters, coupled with a favourable return on investment particularly in high-utilisation charging stations, is promoting the widespread adoption of SiC technology.

Liquid cooling systems are increasingly utilised in ultra-fast chargers, with growing interest extending even to lower-power applications in residential or enclosed settings where noise reduction is a critical consideration.