Electric Vehicles

Charging capacity vs. charging speed: Which is more important?

The Audi E-Tron is an example of a vehicle that balances charging speed and capacity.

Photo courtesy of Audi AG

Should you be worried about the car's range? How fast it can charge? What does it all mean? Why does it matter? Navigating electric vehicle (EV) terminology and measurements can be tough for industry enthusiasts let along the average consumer.

According to Audi, most electric vehicle charging happens at home or work. Generally speaking, charging time does not play a factor during those periods because the model is parked for an extended period of time. Here, the most important thing to consider is how fast you can charge your vehicle at home. How fast a vehicle charges to full depends on the amount you drive your EV and the type of outlet you plug it into to charge.

Audi charging E-TronThe Audi E-Tron is capable of High Power Charging.Photo courtesy of Audi AG

Your EV may be capable of charging at a high rate of speed. However, if your power outlet doesn't allow for the transmission of energy at that high rate, your car won't charge at that rate. There are three main levels of electric vehicle charging:

  • Level 1 - This type of charting happens via a 120-volt AC plug (a typical household outlet connection) and does not require any additional equipment. Generally, this type of charge can deliver two to five miles of range per hour.
  • Level 2 - These connects are either 240-volt (household) or 208-volt (commercial). This is the type of plug that you would typically use for high-energy appliances like a refrigerator or washing machine. These plugs are typically found inside homes, and not in locations that are easily accessible by vehicle charging cord. This outlet can deliver 10 to 20 miles of range per hour, on average.
  • DC Fast Charge - This type of outlet can conduct 480 volts of AC and requires specialized equipment to utilize. It's called "fast charge" for a reason. Vehicles can get 60 to 80 miles of range in just 20 minutes. Most often, these connections are available at public charging locations.

Charging capacity is measured in kilowatt-hours (kWh). When you are shopping for a new EV, you'll see that it is listed as have a certain kWh battery (example: 16 kWh). The reason that batteries are not listed by size is because they consist of a variety of cells. The size of the cells and the chemistry of the material in those cells determines how quickly they expend energy and how quickly they can be recharged.

This is how Nissan is able to have the same size battery in the Leaf and Leaf Plus but the Leaf Plus delivers more range.

Audi charging speed capacity capabilityAudi has detailed how its E-Tron SUV charges versus its competitors.Photo courtesy of Audi AG

Audi is touting the ability of its vehicles to get energy via High Power Charging (HPC). HPC was developed by Phoenix Contact and dictates how quickly a vehicle can charge. The tech allows cars to reclaim a driving range of 100 kilometers in three to five minutes.

The biggest restriction on fast charging abilities is the transfer of heat. The faster the charge, generally, the higher the amount of heat that is produced. Batteries can only take so much heat before they degrade or malfunction.

This creates a tightrope for automakers and battery providers to walk. They need to have a battery with enough range to make the buying public feel comfortable that will charge as fast as possible without damaging the vehicle or the battery itself. The cost and weight of the battery are two additional considerations.

To achieve this mix, many EV charging systems are designed to allow vehicles to charge to 80 percent quickly, but then throttle off the speed and, correspondingly, the heat. The amount of time a vehicle can charge at this high rate is defined as its charging capacity.

Having a high charging capacity means that you can charge faster for longer. Without high charging capacity, the charging speed matters, but not as much.

The rate at which a vehicle throttles up then throttles back down its charging speed is known as the charging curve. Audi advises that an ideal charging curve with maximum output available for a long period of time is the more substantial area that customers should be concerned about. Having a short charge time means less time plugged in, freeing up public charging stations.

Audi offers up for example its E-Tron 55:

"For a range of around 110 kilometres (68 miles), the customer ideally spends just under 10 minutes at the charging terminal. The Audi e-tron 55 reaches the 80% mark after approximately 30 minutes. Even though it takes much longer, for technical reasons, to fill the remaining 20 percent of a lithium-ion battery, fully charging (5% to 100% state of charge) at an HPC terminal takes around 45 minutes.

The lithium-ion battery of the Audi e-tron 55 has a gross capacity of 95 kWh... Liquid cooling ensures that the battery's temperature remains in the optimum range of 25 to 35 degrees Celsius, even at high stress levels or low temperatures. 22 litres of coolant circulates in the total of 40 metres of cooling lines in the four coolant circuits. During direct-current charging with 150 kW, cold coolant takes away the heat that occurs as a result of electrical internal resistance in the battery."

If you cannot charge to the highest advised limit of the vehicle's capability due to a lack of charging infrastructure, it doesn't matter so much about charging capacity. In that instance, charging speed is most important.

Audi E-Tron charging curveThis is the Audi E-Tron 55's charging curve.Photo courtesy of Audi AG

Is a Level 2 charger enough for your needs because when you charge you often charge for hours at a time? Are you in need of fast charging because you're on a road trip and don't want to wait around for hours while your vehicle charges?

Just as automakers are walking the tightrope, so too are those in charge of installing charging stations.

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VW purchased the rights to the iconic Scout name and plans to make new EVs under the brand.

Volkswagen

Automakers bring back names and brands from the past all the time, but it's not every day that a major company purchases a brand name specifically for the purpose of reviving it. That's exactly what Volkswagen just did with Scout, the name of an ultra-popular off-road SUV that was built by International Harvester in the 1960s and 1970s.

As for the types of vehicles we'll see from the brand, we currently only have the renders to go on. The pickup truck and SUV both feature throwback styling that is reminiscent of the original Scout shapes. Beefy off-road tires and lifted suspension are the only other clues available in the drawings.

Volkswagen has its own EVs, and its other brands like Audi and Porsche have made significant progress with electric vehicles as well. That said, VW doesn't really have a solid off-road option from any of its brands at the moment, so the Scout purchase opens doors for the automaker in that arena.

The announcement sounds exciting, but we've still got plenty of time to wait before there's a Scout-branded EV on the roads. Volkswagen said the plan is to release vehicles by 2026, but it won't be sitting idle between now and then. The VW ID.4 is still very fresh and the automaker says it will launch a total of 25 new EVs in the U.S. by 2030.

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First-year Ford F-150 Lightning production numbers doubled
Ford

Ford has begun serial production of the new F-150 Lightning electric pickup truck, marking what could be one of the most important days in recent automotive history. The first trucks rolled off the assembly line at Ford's Rouge Electric Vehicle Center in Michigan today, so America's best-selling truck has finally gone electric. Ford wants to sell two million EVs per year by 2026 and have half of its global sales volume to be electric by 2030.

Ford F-150 LightningPast meets future: Ford's new electric pickup will be the F-150 Lightningautomotivemap.com

Ford has seen extreme demand for the trucks, with 200,000 reservations since the books opened. To deliver, the automaker plans to increase production to an annual rate of 150,000 units by next year, which involved huge investments in the Rouge Center and created hundreds of jobs. Ford's total investment for the F-150 Lightning crests $1 billion across Michigan alone, and has created 1,700 jobs across various facilities in the state.

Ford F-150 LightningThe first production trucks left the factory today.
Ford Motor Company

Though the Lightning starts around $40,000, the most mainstream models will cost much more than that. The F-150 Lightning Pro, while affordable, is a stripped-down truck intended for commercial buyers. It's still a forward-looking electric truck with amazing capabilities, but it lacks much of the creature comforts and features that everyday drivers expect. Higher trims get the latest driver assistance features, including BlueCruise, which is Ford's semi-autonomous hands-free driving assistant. A 12-inch touchscreen is standard, along with Apple CarPlay and Android Auto, navigation, a Wi-Fi hotspot, and more.

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