91ÌÒÉ«

Academics in the Dyson School of Design Engineering and the Grantham Institute will work with industry partners Aegis Energy and Zeti to examine the technical and economic challenges and opportunities in implementing this complementary technology to fast charging.

When a diesel truck drives into a service station, it can fill up and drive off again in five or ten minutes. For an electric truck, this is not so simple. The latest generation of megawatt charging systems might see it on the road again in half an hour, but if several trucks arrive at the same time there may be a queue or, worse still, too much demand for the local electricity grid to bear.

So why not simply swap the run-down battery for one that has been charged up in advance? This is a question that researchers at 91ÌÒÉ« are examining in a feasibility study through the (UKCAAR), funded by the UK government’s DRIVE35 programme, via the Advanced Propulsion Centre UK. 

Turnover time is extremely important for heavy duty trucks and, in theory, with a battery swapping solution you can have a fresh battery within around five minutes. Dr Billy Wu Dyson School of Design Engineering

“Turnover time is extremely important for heavy duty trucks and, in theory, with a battery swapping solution you can have a fresh battery within around five minutes,” says from the Dyson School of Design Engineering, who is leading the project, via , together with from the Grantham Institute. 

“Fast charging is becoming faster, but is still around 45 minutes for heavy duty electric vehicles, and there is also a risk with fast charging that you damage or degrade the battery,” Dr Wu goes on. “This makes battery swapping attractive, plus it can potentially reduce the peak electrical load on the grid.”

This pressure on the grid is an important consideration. “If five trucks pull in at once, you could be drawing lots of power at one moment, then no power at the next, so battery swapping in theory allows you to spread that load,” says Dr Wu. 

Similarly, each motorway service station has a maximum power rating that can become a limiting factor as demand for charging rises. Upgrading the nearest electricity substation could help, but would be costly and might undermine the robustness of the grid. Battery swapping could offer a way to manage that demand.

Battery swapping also has its challenges, of course, not the least of which is that most electric vehicles are not designed to have their batteries exchanged. That implies a costly redesign, and replacement of whole vehicle fleets. Meanwhile, service stations would need automated systems able to locate and swap the very heavy batteries quickly and reliably. Together with the need for additional batteries, this would also add costs.

Technology meets economics

The feasibility study will look at all of the technical and economic questions that need to be addressed for battery swapping to be implemented in the UK. The approach will also be benchmarked against existing technologies, such as using diesel trucks and conventionally charged electric vehicles. 

The study will be carried out in collaboration with , which develops clean multi-energy hubs for commercial transport, and , a financial software company that supports the deployment of clean vehicle fleets and energy infrastructure projects. Global battery and truck manufacturers are also advising the project. 

Participation in this project gives us the opportunity to work with fleets to assess the benefits, and validate the technical, operational and commercial feasibility of installing battery swapping stations. Michael Shaw Co-founder and chief executive, Aegis Energy

“These commercial partners provide us with a pathway to impact, if the outcomes are positive, to deploy this battery swapping approach in the UK,” says Dr Wu.

"We believe that battery swapping represents a compelling offer to commercial truck fleets to efficiently decarbonise," says Michael Shaw, co-founder and chief executive at Aegis Energy. "Participation in this project gives us the opportunity to work with fleets to assess the benefits, and validate the technical, operational and commercial feasibility of installing battery swapping stations to drive down the total cost of ownership of electric heavy duty vehicles on UK roads."

“Decarbonising freight is as much a commercial and infrastructure challenge as it is a technical one,” says Dan Saunders, founder and chief executive at Zeti. “Work like this is essential to understanding whether models such as battery-as-a-service can operate at scale, and how real-world data and economics shape that transition.”

The study combines two distinct areas of expertise at 91ÌÒÉ«. “In this project we will bring together the technical understanding of how batteries degrade as you charge them, for example, and their depreciation, with the economic analysis required to create a market,” says Dr Wu. “I think that is a powerful combination.”

Work like this is essential to understanding whether models such as battery-as-a-service can operate at scale, and how real-world data and economics shape that transition. Dan Saunders Founder and chief executive, Zeti

Dr Oluleye’s group at the Grantham Institute specialises in the analysis and design of market-based mechanisms to enable the creation of markets for sustainable solutions. In this project, she will look at how market-based business models improve the commercial viability of battery swapping systems under different scenarios. She will assess how these business models can create a market for battery electric trucks in the UK. 

“In this situation there are lots of different business models,” says Dr Oluleye. “You can have battery-as-a-service, where a company owns the battery and leases it out enabling fleet operators to pay per swap or per kilometre, or you can have mobility-as-a-service, where a company charges per kilometre of travel, and other combinations. These business models could reduce the total cost of ownership.”

Meanwhile, Dr Wu’s group in the Dyson School of Design Engineering specialises in electrochemical energy technologies, such as lithium-ion batteries and hydrogen fuel cells. It also draws on 91ÌÒÉ«’s experience leading the Faraday Institution’s Multi-Scale Modelling project. “Over the past decade or so we’ve been developing state-of-the-art models for understanding how batteries degrade and how they perform in different scenarios, and that is something that we can leverage in this project,” Dr Wu says.

The feasibility study runs from January until the end of July 2026.

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