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-Tron The 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 capability Audi 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 curve This 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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The AWD ID.4 model is on its way.

Volkswagen

There was a lot of buzz when VW introduced its 2021 ID.4 all-electric crossover with rear-wheel drive earlier this year, but there's plenty more now that the Wolfsburg automaker has added an all-wheel-drive version. The 2021 VW ID.4 AWD gets another motor onboard this compact SUV that brings all-wheel-drive traction. The SUV appeals to buyers in the snow belt states but will also tickle the fancy of performance enthusiasts. Now with motors on both the front and rear axle, there is nearly fifty percent more power, with impressive gains to horsepower and torque as well as the added battery-electric boost to that scoots the 5-seater from 0-60 mph in 5.7 seconds (the RWD model took 7.5 seconds to achieve the same).

2021 VW ID.4 AWD An extra motor brings AWD to the ID.4.Volkswagen

On sale now, the 2021 VW ID.4 AWD Pro starts at $44,870, before federal or other incentives; this is a $3,680 premium over the rear-drive model. The AWD Pro S starts at $49,370; both models are eligible for $7,500 income-tax credits. It's worth noting that current delivery estimates for the AWD Pro are running into 2022. The AWD Pro trim has been rated by the EPA at 249 miles (only 11 miles less than the Pro RWD) while the AWD Pro S has been validated at 240 miles (as compared to 250 miles). The AWD Pro has been rated at 102 MPGe for city driving/90 highway/97 combined; the Pro S gets 93/98/88. Both are rated at 2,700 towing. Competitors include the Ford Mustang Mach-E and Tesla Model Y.

While the AWD and RWD look the same outside, one exterior badge designates the newest variant with an "AWD" badge, plus it gets 0.6 inches of added ground clearance, slightly bigger brakes and sway bars. From the front, the electric SUV has smoothed jelly-bean styling that is highlighted by standard LED headlights and standard black roof rails that sit atop the body-colored roof. From the rear, it wears hatchback-like looks.

2021 VW ID.4 AWD The ID.4's cabin is tidy and upscale, no matter the model.Volkswagen

We drove both the Pro and Pro S versions, with different premium interior trims and found the Gradient Package ($1500) visually upscale and appealing. It brings a black roof with silver rails, along with 20-inch wheels and the availability of King's Red Metallic paint, as a $395 option. The Pro is well-equipped with attractive trim elements and an impressive collection of communication and infotainment technologies. Pro S comes with a glass roof with an electrically-retractable shade and front seats with leatherette upholstery and 12-way power adjustments (including four-way lumbar support and a massage system).

We drove the new ID.4 AWD over a course of 160 miles along a variety of roads to sample its handling and ergonomics. The interior has a clean and open feel with good visibility. Controls and gauges are well-placed and the seatbelts are height-adjustable, while a configurable console holds different drink sizes and has removable cupholders. A futuristic LED "Light" strip with 10 different ambient lighting selections extends across the dashboard and pulses with directional signals, incoming phone calls, navigation prompts and other in-cabin inputs (optional is 30-color lighting selection on the Pro S). Driving is also a bit futuristic with no stop/start button; the vehicle senses the approaching key and can start climate control, unfold side mirrors, unlock doors and illuminate door handles at night, among a number of other high-tech features. There is 30.3 cubic feet of stowage behind the rear seats and up to 64.2 cubic feet with the second row folded. Under the floor storage holds the charging cable and small items. Pro S has an adjustable trunk floor that can be raised and lowered and a ski passthrough.

Pushing the brake pedal triggers the ID.4 to begin motoring, with the option of a "D" mode for typical driving or "B" for a more regenerative driving experience. Travel Assist brings semi-autonomous driving. Notable is the fun and responsive torque-on-tap, well-balanced direct steering and a suspension system that allows the small compact to maneuver well through traffic and along twisty roadways, as well as an impressive turning radius. The vehicle dynamics control system is integrated with the stability control system and an electronic differential to seamlessly engage the front axle, when needed. Volkswagen has added a different asynchronous motor to the front with a permanent-magnetic synchronous motor at the back for a combined 295 hp. and 339 lb.-ft. of torque.

2021 VW ID.4 AWD The ID.4 AWD will start shipping in early 2022.Volkswagen

Carried over are 82-kWh battery packs and the 5 to 80 percent fast-charging time of 38 minutes, when using 125kW fast-charging. VW says it can add 62 miles of range in 10 minutes; home charging on a Level 2 charger is projected to take approximately 7.5 hours for a full charge.

Of note: VW includes three years of complimentary charging up to 125 kW, with any ID.4 purchase or lease; VW Group's Electrify America charging network has over 650 stations and more than 2,700 fast chargers.

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Electric sports car

Porsche Taycan has outsold the 911 in 2021

The Taycan has outsold a few Porsche models so far this year.

Porsche

The Porsche Taycan is an impressive EV with speed and build quality to shame almost anything else on the road. As we learned from Porsche today, those attributes resonated with buyers, as the Taycan outsold the Porsche 911 during the first nine months of 2021.

Porsche Taycan The Taycan's steep starting price doesn't seem like much of a sticking point for buyers.Porsche

Yes, the electric car that starts at almost $83,000 outsold the most iconic sports car of all time. However, Porsche's had a good year, and it's not all thanks to the Taycan. In today's SUV-crazed world, it's not surprising to see that the Cayenne is still Porsche's most popular model. The automaker sold 62,451 of its flagship SUV in the first nine months of the year. The Macan sold a respectable 61,944.

Now, consider that the Taycan – a brand new, expensive, all-electric car – sold almost half as many units as those two iconic SUVs. Further cementing its place in the Porsche lineup, the car outsold the 911 by almost 700 units and decimated sales of the 718 Boxster and 718 Cayman, which combined sold 15,916 units. The Panamera, which offers a similar body style to the Taycan, sold 20,275.

Porsche SUVs The Cayenne and Macan both sold very well.Porsche

Porsche has had a good year in all markets it serves, but the U.S. market showed the strongest sales growth, climbing to 51,615 vehicles sold in the first nine months of the year. That's a 30 percent jump from 2020, and the rest of North America was just as strong with a combined 29 percent increase in growth. China did the most to propel Porsche's sales skyward, with almost 70,000 cars sold there.

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