The number of electric vehicles (EVs) on our roads will continue to increase, slowly transitioning the transport system from combustion engines to electric motors. The uptake of EVs will put a strain on the electric charging infrastructure and will see many travellers at charging points along the motorway for many hours. EV charging technologies have slowly improved and decreased the charging time along with improvements in battery efficiency in EVs.

Some manufacturers on the other hand are experimenting with the concept of swapping EV batteries out with a fully charged one. Nio, a Chinese EV manufacturer has rollout battery swapping stations across China. These swap stations enable their customers to swap out their discharged batteries with brand-new batteries without the need to wait around to charge their current battery.  

How Does Battery Swapping Work?

When the EV battery is low, you can drive into a swap station that reassembles a car wash facility. You drive in and the swap station will lift the car to uninstall the depleted battery. Once the depleted battery is taken away, the station will then install a fully charged battery in the vehicle. When successfully installed the EV can be driven away to the next destination. NIO suggests that their process takes between 3 to 5 minutes complete.  

Video: Is Nio Battery Swapping Superior to Charging?

Positives of Using Battery Swapping

The main strength of battery swapping is that drivers can be on their way within a shorter time frame when compared to charging an EV. The depleted batteries that get taken out are charged for the next EV. Companies that run the swap stations can take advantage of clean energy sources such as solar power to charge up the batteries. As these batteries are charged slowly this can extend the lifecycle of the battery. Battery swapping can be used for general users but would also benefit a fleet of vehicles such as large vehicles.

Weaknesses

Money

A huge downside is a lot of money would be needed to purchase the land and build the station themselves to provide adequate coverage for EV users. Swap stations take up a lot of space and an efficient charging infrastructure will need to be built to charge the batteries at an efficient rate.

Extra Batteries

To cater for swap stations more EV batteries will need to be produced which will use up natural lithium resources that are already low due to increased EV production. Some companies offer different battery capacities which will add the number of different capacities available for users. Producing extra batteries for one manufacturer will be exhaustive on resources. If all companies start implementing swap stations, there will be swap stations everywhere with their bespoke batteries floating around on the market. A universal battery with the same construction will need to be agreed upon with all manufacturers to prevent manufacturer-dedicated swap stations.

When a swap station has swapped out all available fully charged batteries, the station can no longer serve other EV cars until the batteries are charged. To serve a large volume of EVs, swap stations will need to stock enough batteries. Sufficient battery stocks will be greatly needed if a swap station is located on a road with heavy traffic flow.

Battery Ownership

Batteries are normally owned by the EV owner. However, swapping batteries means that you are no longer the owner of the battery, and it is owned by the battery provider. The depreciation of the battery lifecycle will vary depending on previous uses and charge cycles, EV owners will not be able to maintain the efficiency of the battery like a traditional EV owner would.    

Summary 

Swappable car batteries are a good concept to speed up the charging process when travelling. To make swap stations a tangible service, EV owners will require an extensive swap station network and many available batteries ready to swap for depleted batteries.

As swap stations require more production of batteries for EVs available this could run the risk of depleted natural resources to produce batteries for EVs in current production. Depletion of natural resources could prevent the development of battery and charging technologies as well as stall the uptake of EVs.

Swap stations could benefit large vehicles like trucks as they would require large battery capacity that would take longer to charge than smaller EVs. Swap stations have a lot of potential and cater for the need to reduce charging wait times. There are also a lot of weaknesses to consider such as the number of batteries needed to be produced to set up a swap station as well as the natural resources needed. It will be interesting to see whether swap stations can be sustainable in the long run, especially when batteries need to be renewed once they hit their charge cycle limit and depreciation of holding its charge.