Many who reject the option of an electric vehicle say that they’ll consider one only when EVs have the range for occasional long-distance drives and can recharge about as quickly as you can refill a car’s tank with gasoline. Well, that time is nearly here—a lot sooner than even many experts in charging technology anticipated.
Charging hardware being installed this year will be upgradable to the capability to restore 300 miles or more of driving range in just 10 minutes. In “charging miles per hour,” as the upstart electric-car maker Faraday Future and others have called it, that’s 1800 mph. Although designed to be capable of that rate, few of these new-generation public-charging cabinets will be equipped to do so initially, in part because few cars are ready to swallow electrons as quickly as these devices can pump them into the batteries. The point is, we’re at a place in the evolution of electric cars in which commercial charging hardware is no longer trying to play catch-up to the batteries and the cars. Instead, charging technology is poised to be well ahead of the hardware on most cars, to a point that surprises industry insiders. Current DC fast charging, on either the CHAdeMO or Combined Charging System (CCS, or Combo) interfaces, runs at up to 50 kW—even though some carmakers list higher numbers that are still only theoretically possible. Both systems are in the process of being upgraded to be compatible for up to 150 kW, with the first publicly accessible chargers at that rate expected to be online late this year. Ultrafast chargers with compatibility to 350 kW and beyond—the charging ability that would get us nearly to gas-station fill speeds—are in the works, with a 350-kW test installation underway in Baker, California. 350-kW EVgo station – Baker CA “
If you had told me seven years ago that we would be here talking about 350 kW, I would not have believed it at all—and now we’re talking about much more,” said Johan Peeters, vice president for marketing and sales at ABB, one of the leading producers of charging hardware. 460 kW: Soon, the New Fastest Charging Lane How much more? Within a few years, a new high-powered CCS standard, employing a special liquid-cooled version of the connector that’s backward compatible with today’s vehicles, will be able to provide DC fast-charging power up to 460 kW, 920 volts, and 500 amps. That will surpass even the seemingly unbelievable 800-volt figure that seemed like far-off vaporware in 2015, when Porsche mentioned it in conjunction with its Mission E concept. That would allow more than 250 miles of recovered range in as little as 15 minutes. Even at such rates, experts caution that you’ll need a battery pack with range about 25 percent longer than the distances you seek to drive between charges. No matter the size of the pack, truly fast charging happens only for the first 80 percent of the capacity, Peeters noted, comparing it to pouring a glass of beer. Much depends on the technique and conditions, he said, but “you have to slow down for the last 20 percent or it will foam over.” Part of what has driven these deployment plans for fast-charging systems of 150 kW and higher, according to Peeters, is that lithium-ion battery packs are becoming more affordable—and thus larger—more rapidly than was anticipated some years ago. “Long story short, if you don’t have an EV with a 40-kWh battery, next year you’re out of business. It’s that simple,” he said. With current technology, cars with batteries in the 40- to 60-kWh range, of which there will soon be many, will take most of an hour to regain 80 percent after being fully discharged (or as near to that state as automakers will allow them to get). If drivers are heading out on long weekend drives, that hour is often too long for their purposes, Peeters and other charging-industry representatives argued at a recent panel on the topic. Yet, not everyone agrees that a bigger battery corresponds to the need for more fast-charging capability. “It really comes down to use case,” said Fred Ligouri of General Motors, who pointed out that the Chevrolet Bolt EV with its 60-kWh battery pack is easily capable of handling any daily-driving need for the vast majority of its drivers as well as most weekend-driving chores. Cross-Country Capacity for Premium EVs
Premium EVs will be distinguished from the proletarian versions not only by their larger battery packs but by their ability to charge those packs very quickly, a point Tesla is already illustrating with relatively modest capacities in comparison to what’s being proposed for the future. Tesla CEO Elon Musk has hinted that the company intends to go well beyond 350 kW. Chargers on the company’s Supercharger network today are capable of 145 kW, although Tesla vehicles charge at a maximum of 120 kW. As we discovered during our long-term test of a Tesla Model S P85D, cross-country travel is possible, but 45-minute Supercharger stops prove tedious, making quicker charges an enticing prospect. To accommodate both mainstream models at 50 kW and future premium models at 400 kW, commercial charging-hardware manufacturers and commercial charging networks need a lot of flexibility built in. That’s why several of the leading charging-equipment suppliers are looking at modular upgradable systems. ChargePoint took over all of GE’s commercial charging stations earlier this year and now claims to be the world’s largest charging network. The company has announced a new Express Plus architecture that’s 1000-volt compatible and employs combinations of liquid-cooled power modules and power cubes. The company notes that a car of comparable efficiency would recover 45 miles in 15 minutes from a 50-kW DC fast charger or 370 miles of range in the same time with 400-kW hardware. ABB, too, has designed its chargers—which ChargePoint rival EVgo will implement—with grid stabilization in mind, so that one of its 1.2-MV (AC) substations can power six of these dual-standard ultrafast chargers. new-generation ABB DC fast chargerWith hardware that’s built to be upgraded over time, providers also need to be careful where they locate stations. As Michael Jones, ChargePoint’s vice president of sales, pointed out in a recent presentation, 400 kW equals the power demands of an entire grocery store.Because of improved, next-generation hardware, home charging may move from today’s rates of 3 to 7 kW up to 10 kW or beyond, while up to 50 kW (from 20 kW or less today) will be found at so-called Level 2 commercial charging locations, those found at shopping centers, restaurants, and parking lots. A third tier of commercial chargers will be focused around providing “charging on the road”—at the rapid rates cars need to quickly regain a significant amount of charge. For cars with smaller batteries, that would be up to 150 kW, while mainstream, midmarket EVs would offer 120- to 150-kW rates, and top-segment models would be capable of charging at 300 kW or more. A Host of Expensive Issues As these ultrafast chargers come online, public-charging providers (and automakers) will be faced with new issues. Beyond higher initial costs, these chargers can cost a lot to operate because of surcharges known as demand charges, which are levied by public utilities for energy draws beyond typically expected levels. According to EVgo, these demand fees make up about 80 percent of the operating costs for their chargers. Installing more stalls per site is one way to smooth out usage, bringing the demand-driven expenses down. 2016 Nissan Leaf at DC fast charger Another issue is that—as programs such as Nissan’s No Charge to Charge have illustrated—users tend to opt for the fastest charger their vehicle can use, whether they need that faster rate or not. The Bolt EV’s predecessor, the Chevrolet Spark EV, saw about 80 percent of units sold with optional fast charging. Despite the Bolt’s mammoth improvement in range (238 miles versus the Spark’s 82, per the EPA), GM expects at least that same 80 percent will opt for fast charging on the Bolt EV. Automakers are quick to point out that ultrafast charging won’t come cheaply; it involves additional weight in the cars (for batteries and cooling systems) and research and durability testing to make sure battery packs can take it. Nevertheless, the newest fast-charging hardware paves the way for a handful of vehicles that will be able to make use of it. These include the Porsche Mission E, the Audi e-tron, and perhaps the Lucid Air and the Faraday Future FF91, that will start arriving in 2018 and 2019.
Via Car and Driver