How 5-minute battery swaps could get more EVs on the road

Charging has emerged as the primary way people keep their EV batteries full of juice while on the go, but some companies have an alternative in mind that they think could be even quicker than the fastest chargers today: battery swapping.

Today, a San Francisco–based startup called Ample demonstrated its new battery-swap system, which it says can exchange a depleted EV battery for a fresh one in five minutes.

Ample joins several other companies, past and present, with similar ideas. Battery swapping aims to match the convenience and speed of visiting a gas station, which proponents say could help strengthen the case for EVs by making it faster to replenish a car’s range. But some experts are skeptical, viewing battery swapping as an expensive solution that will at best serve a narrow niche within the future of electric transportation. 

Ample’s new swapping stations look like Silicon Valley–designed car washes, all gleaming white and rounded corners. “The whole vision is that we want to provide an experience that is as fast, affordable, and convenient as gas,” said Hamid Schricker, Ample’s director of product, as he gave me a video tour.

An Ample station has the footprint of roughly two parking spaces and offers drive-through service. When a vehicle is ready for a swap, the driver motors up to the station. A door slides up, revealing a platform inside. After navigating into position on the platform by following the instructions on screens inside the station, the driver hits a button in a connected app to start the swap. The station’s platform lifts the vehicle and its occupants several feet, and then the internal machinery gets to work, removing the used batteries in the vehicle and installing fresh ones. When the swap is finished, the platform lowers the vehicle back down to the road, and the driver can take off, charged and ready to go.

The depleted batteries can then be charged up over several hours and installed in another vehicle. While the batteries can be charged more quickly, slowing things down helps prevent degradation, says John de Souza, Ample’s cofounder and president. The number of swaps will be limited by the connection to the electrical grid, so a station with a 100 kilowatt connection will be able to charge and swap 48 batteries in the course of a day, each with a capacity of 50 kilowatt-hours.

Ample has a dozen of its first-generation swapping stations installed around the San Francisco area. Together, they’re performing a few hundred swaps each day at roughly 10 minutes apiece, de Souza says. The startup is partnered with Uber, aiming to demonstrate that battery swapping could help in demanding applications like ride-share fleets. But the ultimate vision is a drop-in replacement that allows people on commutes or road trips to swap out their EV battery and be on their way.

Building swapping stations will be more expensive than building superchargers: Ample declined to share exactly how much it planned to spend on each station, saying only that they would be less expensive than other battery-swap facilities that can cost half a million dollars to build and install.

A fork in the road

Ample is far from the first company to pursue battery swapping. Tesla Motors explored the concept, demonstrating the technology in its Model S in 2013 before eventually abandoning the plan in favor of its supercharging network.

Better Place was one of the most well-known battery-swap ventures. The startup was founded in 2007 and worked with automaker Renault, building a network of a few dozen swapping stations in Israel. But after raising some $850 million, the company failed to get more automakers and drivers on board and eventually filed for bankruptcy in 2013.

The specter of Better Place hangs over battery-swap efforts today, but de Souza says Ample’s approach addresses issues that sank previous iterations of the technology.

For a third-party company like Better Place or Ample to gain ground, it must find a way to be compatible with vehicles hitting the road. But getting automakers to converge on a battery is a challenge: companies are increasingly choosing different battery designs and chemistries for different models.

Ample’s solution is a modular system. Rather than take the whole battery out at once and screw on a fresh one, the startup plans to fit several smaller packs into a battery frame. This cuts down on the cost for machinery needed to move batteries, since the pieces are smaller, de Souza says.

And crucially, the modular design could make it easier for automakers to sign on, de Souza says. Ample’s vision is for vehicle makers to deliver their cars with an empty space where the battery should be. Ample can then build an envelope for that specific vehicle and plug in as many modules as will fit.

The number of modules can be customized both to the size of the vehicle (a compact car will hold fewer than a large SUV) and to driver needs—someone might install just a few modules for daily driving but load up when going on a long trip, de Souza says.

So far, Ample’s swapping stations are compatible with two vehicle models that have the company’s special batteries installed: the Nissan Leaf and the Kia Niro. According to de Souza, the system works with 13 vehicle models, though no other automaker partners have been announced.

Some experts are skeptical that even this altered vision of battery swapping is practical. “I think battery swapping is unlikely to be the primary way that we manage batteries for the general vehicle fleet,” says Jeremy Michalek, a professor of engineering and public policy at Carnegie Mellon University.

Every make and model of electric vehicle on the road today has a different battery design, shape, and chemistry. Swapping requires standardization, and even if modules can provide some customization, they would still be a major constraint for automakers. “Putting the same size modules into different vehicles is very limiting,” he says.

In the driver’s seat

While third-party companies like Ample are aiming to create a standardized swapping ecosystem, some automakers are establishing their own infrastructure that gives them more control over the details.

In China, Nio has established itself as a major player in battery swapping. The automaker has about 1,400 commercial battery-swap stations deployed; most are in China, though the company has started expanding operations into European countries like Norway and the Netherlands as well. The goal is to have 2,300 stations installed by the end of 2022. 

The major selling point for customers is convenience, says Fei Shen, senior vice president of power management at Nio. “If we do battery swaps, the time is almost equivalent to refueling,” he says.

Nio’s swap stations move its batteries around all in one piece. The company offers three different battery options with different capacities, with each fitting into any and all vehicles it makes.

Nio’s customers don’t have to swap batteries—the vehicles can top off at fast-charging stations that Nio also builds—but the option is there, and people are using it, Shen says. The automaker has 300,000 vehicles on the road, and about 60% of drivers have used swap stations, according to the company’s data. In total, the company’s stations have performed 20 million swaps, and its newest stations can perform 400 a day. 

Nio isn’t the only company going after battery swapping in China. In total, six Chinese companies including Nio plan to have 26,000 installed battery-swap stations in the country by 2025, according to projections by BNEF, an energy research firm.

Hitting the brakes 

These efforts might succeed at the higher end of the market, but it’s not likely that companies like Nio will be able to serve the vast majority of drivers, says Gil Tal, director of the plug-in hybrid and electric-vehicle research center at the University of California, Davis. “I think it’s a very expensive solution,” he says. 

Not only will battery-swap companies need to build expensive swap stations (which, according to some early estimates, can run roughly double the cost of an equivalent fast-charging station), but they’ll need to maintain the complicated machinery involved. “It’s very difficult to manage a lot of swap stations—all of them have to have a high reliability,” Shen says. 

Nio and some other battery-swap companies plan to charge customers a monthly fee for their batteries and swapping privileges. In Norway, the cost for Nio’s lowest-capacity battery is roughly $135 monthly (owning the battery outright would cost around $8,500).

The marginal time savings of a battery swap might not be worth that extra cost and trouble. “Most EV drivers don’t drive more than the range of the car,” Tal says. For the few who do, he adds, stopping at a fast charger for 15 to 20 minutes won’t be a bigger barrier than stopping for a swap. 

Fast chargers are getting quicker all the time, with the Tesla supercharging network offering up to 250 kilowatts of charging power today—enough to add about 200 miles of range in 15 minutes. Other fast chargers deployed today can hit 350 kilowatts

Companies may be able to deploy battery swapping where people will pay a premium for speed: luxury vehicles, or for fleets of delivery trucks or taxis. It’s more likely to be helpful in the narrow range of cases where stopping at a fast charger is a major inconvenience. But at least for now, once we ditch gas pumps, we’ll be plugging in on road trips.

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