SiC power electronics could slash Tesla Model S cost

August 13, 2014. Wide-bandgap (WBG) materials such as silicon carbide (SiC) and gallium nitride (GaN) are best positioned to address emerging power electronics performance needs in electric vehicles (EVs), with SiC displacing silicon as early as 2020, according to Lux Research.

As silicon struggles to meet higher performance standards, WBG materials are benefiting critically from evolving battery economics. On Tesla Model S, for example, a 20% power savings can result in gains of over $6,000 in battery cost, or 8% of the vehicle’s cost.

“Efficient power electronics is key to a smaller battery size, which in turn has a positive cascading impact on wiring, thermal management, packaging, and weight of electric vehicles,” said Pallavi Madakasira, Lux Research analyst and the lead author of the report titled “Silicon vs. WBG: Demystifying Prospects of GaN and SiC in the Electrified Vehicle Market.”

“In addition to power-electronic modules, opportunities from a growing number of consumer applications—such as infotainment and screens—will double the number of power-electronic components built into a vehicle,” she added.

Lux Research analysts evaluated system-level benefits WBG materials are bringing to the automotive industry and predicted a timeline for commercial roll-outs of WBG-based power electronics. Among their findings:

The power-saving threshold is lower for EVs. At 2% power savings, if battery costs fall below $250/kWh, SiC diodes will be the only economic solution in EVs requiring a large battery, such as the Tesla Model S. However, for plug-in hybrid electric vehicles (PHEVs), the threshold power savings needs to be a higher 5%.

SiC is ahead in road to commercialization. SiC diodes lead GaN in technology readiness and will attain commercialization sooner, based on the current Technology Readiness Level (TRL). Based on the TRL road map, SiC diodes will be adopted in vehicles by 2020.

Government funding is driving WBG adoption. The U.S., Japan, and the United Kingdom, among others, are funding research and development in power electronics. The U.S. Department of Energy is spending $69 million this year on advanced power electronics and electric motors and is defining performance and cost targets; the Japanese government funds a joint industry and university R&D program that includes Toyota, Honda and Nissan.

The report, titled “Silicon vs. WBG: Demystifying Prospects of GaN and SiC in the Electrified Vehicle Market,” is part of the Lux Research Energy Electronics Intelligence service.

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