Breathe’s charging software is unlocking faster charging, longer-lived EV batteries

Charging can be a risky business. Done too aggressively, it will degrade the battery, shrinking its lifespan at best or triggering a fire at worst. So, manufacturers have tended towards conservatively managing charging protocols. But that means slower charging, ever the frustration for electric vehicle (EV) drivers.

Spinout company Breathe has worked out a way around this by zeroing in on an often-overlooked aspect of batteries: the software that controls charging. It has solved a longstanding challenge in battery modelling that, since being implemented in the software, has improved batteries’ longevity and sped up charging. And by eking out every last bit of batteries’ potential, the company hopes to cut costs for manufacturers – with the savings passed on to consumers.

Breathe has raised over £16 million in its latest funding round, and its software, embedded in Volvo EVs, has been shown to speed up charging from 10% to 80% capacity by nearly a third. These are among the achievements that have landed Breathe’s Co-Founder, Dr Ian Campbell, a 2026 Princess Royal Silver Medal from the Royal Academy of Engineering for his leadership in battery technology.

Software-defined charging

Conventional charging protocols rely on batteries’ measurable properties – current, voltage and temperature. But these don’t tell the full story. “The reality of the situation is that everything that matters to the battery is happening inside,” says Campbell.

What further complicates things is the fact that batteries are sealed metal cans and can’t easily be cracked open to see what’s going on. Lithium-ion battery modelling, the field Campbell’s PhD studies was in, aims to decipher their electrochemical, mechanical and thermal behaviour through simulation.

“When you understand what's happening or what's not happening and how they're dying or how they're surviving, you're able to make much better decisions about how to design them and how to control them,” he says. This expertise – coupled with concerns about air pollution and a shared frustration with conventional charging protocols – led Campbell and a lab colleague, Dr Yan Zhao, to spin out Breathe in 2019 from Imperial College London.

With their former supervisor, Professor Greg Offer as Breathe’s Chief Scientist, the team set out to build software to adaptively control charging, through simulating batteries’ internal states. The catch was that this usually involves massively complex, costly computational models that couldn’t run on the electronics normally embedded in EVs, or indeed laptops or phones, another target market.

The team started “with a clean sheet of paper, taking an atomic approach”, explains Campbell, only introducing necessary equations and methods, and building upwards. With this approach, the company has been able to fit effective simulations on battery management systems in electric cars, as well as for small electronic devices.

Volvo Cars, Polestar and Bang & Olufsen are among the manufacturers who have seen the benefits to working with Breathe. “You don’t have to add any extra hardware,” says Campbell. “It’s also incredibly inexpensive.” And it has yielded significantly faster charging – 38% in the case of the fully electric Volvo ES90 – as well as more durable batteries.

De-risking battery design

Following its successes with early adopters, Breathe is working to push out its adaptive charging to more EV customers. But their long-term ambitions lie in improving battery design.

The idea is to de-risk R&D, making it cheaper for manufacturers. Developing a new EV battery currently involves battery engineers testing out numerous physical prototypes, varying the cathode and anode materials and electrolyte mixtures and selecting the best-performing combinations.

Breathe plans to expedite the process with its simulation tools. The company works with materials scientists and engineers to build libraries of each different component. Their customers will be able to virtually test combinations and take forward the candidates that are most likely to perform and cost as needed.

The £16 million series B funding round Breathe raised last year, including funding from the Volvo Cars Tech Fund, will finance expanding its existing software and help the company to bring its design tools to manufacturers earlier in battery development.

Campbell compares this to the way that simulation is now integral to Formula 1, with computational fluid dynamics and stress and strain simulations. “In these industries now, no one would dream of building  the hardware up before they simulate it,” says Campbell. “We think batteries are certainly on track for that same route.”

Batteries have long been the most expensive materials component of EVs. Now, with Breathe’s help, the potential is there for the industry to deliver significantly lower cost, better-performing batteries that help accelerate the rollout of electric vehicles.