Electric vehicles (EVs) and hybrids are one of the most critical parts of the fight against climate change. Transportation accounts for 29% of all greenhouse gas emissions, so moving away from fossil fuel-powered cars is a must. Automotive semiconductors need some improvement for that to happen, though.
Traditionally, most semiconductors, like those in EVs, are made of silicon. While this material has plenty of benefits, its limits have become increasingly clear as semiconductor use rises. It heats quickly, has limited efficiency, can’t handle higher voltages and tends to lose conduction.
Imperfect semiconductors translate into underperforming EVs and hybrids, limiting their viability as a replacement for traditional vehicles. Wide-bandgap semiconductors provide various advantages over conventional silicon alternatives, and as such, can improve EVs and hybrids.
What Is a Wide-Bandgap Semiconductor?
Bandgap refers to the minimum amount of energy required for an electron to move from the valence to the conduction band. The wider the bandgap, the more power it takes for electrons to act as conductors. Wide-bandgap materials like gallium nitride (GaN) and silicon carbide (SiC) have a bandgap of around 3.2 electron volts, compared to silicon’s 1.2.
Wide-bandgap semiconductors can withstand higher temperatures because of this property. That means they can sustain high voltages or be thinner to sustain the same voltage. Less risk of overheating also means they’re not as likely to malfunction under the same or more strenuous conditions.
Thinner semiconductor materials can operate at the same voltage with fewer conduction and switching losses. This, in turn, improves their efficiency as a power supply. Here’s how these benefits translate into improvements for EVs and hybrids.
Minimizing Costs
Cost is one of the most significant barriers in the way of increased EV adoption. An electric car can cost thousands more than the equivalent gas-powered alternative, at least upfront. This is a multifaceted issue, but automotive semiconductors play a considerable role in that price discrepancy. Wide-bandgap materials can help.
With traditional silicon components, EV or hybrid batteries require more or larger semiconductors to handle more power. Since wide-bandgap semiconductors can sustain higher voltages with less material, they don’t have that problem. Automakers can deliver the same amount of energy without adding as much material. This saves costs and makes EVs more affordable.
Since GaN and SiC semiconductors are also more efficient, they improve EV and hybrid cost-to-performance ratio. This is how the Tesla Model 3, widely recognized as one of the best EVs for its price, can remain both affordable and efficient. These efficiency gains lower charging requirements, too, decreasing lifetime ownership costs.
Extending Ranges
Another issue with many EVs that turns consumers away is their limited range. Older models, and many cheaper new ones, can’t travel very far before needing to recharge. Carmakers can make many adjustments to improve EV range, but silicon’s limits are one of the primary factors behind poor battery efficiency.
Silicon starts to dissipate more energy at higher frequencies, a process called switching loss. That means silicon automotive semiconductors become less efficient as demands climb higher. GaN and SiC semiconductors exhibit switching losses at a much slower rate, so they don’t lose as much power at higher frequencies.
Fewer switching losses translate into EV and hybrid motors that stay efficient for longer. Consequently, cars using these wide-bandgap semiconductors have longer ranges, even when their drivers push them to higher speeds. As more electric and hybrid vehicles feature these semiconductors, they’ll become more efficient as a group, enticing more buyers.
Improving Reliability
Generally speaking, EVs and hybrids have fewer maintenance requirements than gas-powered cars because they have fewer moving parts. There’s always room for improvement, though, and better semiconductors can improve the electrical system’s reliability. On top of reducing lifetime costs, this increases driver satisfaction.
Since GaN and SiC have much higher heat tolerances than silicon, they’re less likely to malfunction from high temperatures. No matter how hard drivers push their motors or what kind of conditions they drive in, these semiconductors can handle it.
More resilient semiconductors prevent issues outside of a car’s engine, too. Electronics like blind-spot sensors and backup cameras all rely on chip technology, which wide-bandgap semiconductors can improve. GaN and SiC’s heat tolerance ensures electrical systems function correctly while multiple features run at once. This reliability is particularly important for EVs since inefficiency in these systems could impact the car’s range or performance.
Reducing Carbon Footprints
While EVs and hybrids are far more sustainable than their gas counterparts, they’re not entirely emissions-free. Electric cars may not release carbon while driving, but they do when charging. Roughly 60% of U.S. electricity comes from fossil fuels, so excessive charging can still do environmental damage.
Wide-bandgap semiconductors help reduce EV and hybrids’ carbon footprints by requiring less frequent charging. Silicon semiconductors typically require large heatsinks because of their low heat tolerance. Wide-bandgap alternatives don’t need them, which reduces weight and improves efficiency.
Materials like GaN and SiC can also sustain the same amount of power with fewer materials, further saving weight. Since these vehicles are so much lighter, they’ll go farther before needing to recharge. This reduces electricity-related emissions.
Wide-Bandgap Semiconductors Could Reshape the Automotive Industry
Silicon is a remarkable material, but now that electronics have pushed it so far, its weaknesses have become more evident. Wide-bandgap semiconductors are the ideal alternative for high-intensity applications like EVs and hybrids, and this will become increasingly clear as more automakers use them. Before long, GaN and SiC will likely replace silicon as the industry standard for automotive semiconductors.
As more EV and hybrid manufacturers embrace these semiconductors, their vehicles will become a more viable replacement for gas-powered cars. They’ll be more affordable, reliable, green and efficient. These benefits will attract more buyers, slowly leading to more sustainable autos worldwide. That’s something worth striving for.
Image Credit: Laura Ockel via Unsplash
Coinsmart. Beste Bitcoin-Börse in Europa
Source: https://datafloq.com/read/how-are-wide-bandgap-semiconductors-improving-evs-hybrids/14868
