What’s in Store for Next Generation EV Charging Stations?
Recent extreme weather events have highlighted the need to shift towards more renewable sources of energy. We have also seen how this extreme weather can significantly impact outdated power grids, leaving cities in the dark for extended periods. The new administration has ambitious plans to tackle climate change threats and aging infrastructure in order to build a reliable foundation for the future.
If enacted, a large part of The Infrastructure Investment and Jobs Act focuses on furthering electric vehicle adoption for both personal and commercial applications. In 2021, sales of new vehicles have continued to increase due to pent up demand and government stimulus packages. In order to increase the percentage of EVs on the road a few issues need to be addressed, mainly cost and range anxiety.
Range anxiety is impeding rapid growth for electric vehicles
The biggest hurdle for electric vehicle adoption is range anxiety and the uneven distribution of EV charging stations. While many EV owners charge their vehicle at home, drivers that live in apartments or housing complexes may need to rely on public charging infrastructure. According to the Department of Energy, there are about 44,000 public EV charging stations in the U.S. that provide 120,000 charging ports. However, these EV charging stations are not evenly distributed throughout the U.S – over 30 percent are located in California. With over 130,000 gas stations in the U.S. and a lagging charging network, drivers are concerned that they will not find a place to recharge before they reach the end of their range.
Another disadvantage is the amount of time it takes to charge an EV versus filling a tank with gasoline. There are currently 3 levels of charging – Level 1 (L1), Level 2 (L2), and DC Fast. Many L1 chargers are used at home and charge the slowest – about 4-6 miles of range per hour of charging. Public EV charging stations typically employ either Level 2 or DC Fast charging speeds.
A growing need for DC fast EV charging stations
While Level 2 equipment is sufficient for overnight charging or when drivers can afford longer stopovers, long distance road trips present a challenge. DC fast chargers with 50kW output are capable of topping off a vehicle in about an hour – but this is still too long compared with refueling internal combustion engine vehicles. Many vehicles are limited by their acceptance rate – current EVs typically max out at 50kW with a few models capable of higher power ratings. As technology improves, and charger output and battery acceptance levels increase, charging speeds will accelerate. This presents new challenges for design engineers such as vehicle compatibility, robust component selection and heat management.
Thermal considerations for rapid EV charging stations
New Extreme Fast Charging (XFC) technology is on the horizon however, charging at that 350kW and higher generates a massive amount of heat. If not properly managed, this leads to battery degradation over time and also carries inherent safety risks. Excessive heat can also present a problem during component selection – many parts are prone to failure when thermal conditions fall outside of a defined range. Through a combination of liquid cooling in the cable and active cooling in the station body, design engineers have been able to achieve faster charging speeds while maintaining expected safety and reliability standards.