Hydrohertz’s technology is its patented Dectravalve, a compact, intelligent, multi-zone valve system that delivers incredibly precise heating, cooling, or energy recovery of an EV battery.

“Optimising the operating temperature of an EV battery is crucial to both its short- and long-term performance,” explained Hydrohertz CTO Martyn Talbot. “Unlike traditional systems which treat the entire pack uniformly, the Dectravalve allows for targeted heating or cooling of individual modules within the battery. This means it can keep every part of the battery pack at a consistent, optimum temperature, maximising the performance of the cells across the entire pack.”

In an ultra-fast charging test with leading independent battery experts Warwick Manufacturing Group (WMG), a 100kWh Lithium Iron Phosphate (LFP) EV battery equipped with Dectravalve kept its hottest cell at under 44.5°C, maintaining a temperature difference of only 2.6°C across the whole pack.

This compares favourably to typical fast-charging conditions in today’s EVs, where peak cell temperatures regularly rise to as much as 56°C and the temperature difference across the pack can exceed 12°C. Once cells push beyond 50°C, charging power must be throttled to avoid ‘lithium plating’ (internal damage to cells) and long-term damage to the pack, meaning fast charging tapers off much earlier than advertised, significantly increasing the overall charge time.

In contrast, the Dectravalve-equipped battery never left the optimum high-power zone. It kept every module performing at peak efficiency, with no thermal weak spots holding the system back. Simply put, the Dectravalve-equipped battery stayed cool, even when pushed to its limits.

In the same test, Dectravalve demonstrated that charging times can be slashed by up to 68%, meaning a typical 30-minute 10-80% charge on a 350kW fast charger could drop to around 10 minutes, putting EV charging on a par with conventional petrol/diesel vehicle refuelling times.

And because the cells are operating at optimum temperatures during all conditions – i.e. not just when charging – the efficiency of the battery can be increased, delivering up to 10% more real-world driving range. With a typical mid-sized EV that could mean another 30-40 miles, providing more usable driving distance per charge, reducing EV running costs and energy consumption.

Safety is also significantly enhanced as maximum cell temperatures can be capped, preventing overheating, minimising risks of lithium plating (internal damage to cells) and thermal runaway (overheating leading to thermal incidents). And because the whole battery is operating at optimum temperature, Dectravalve can also extend its life, putting each cell under less strain so it can stay within a safer temperature range, protecting state of health (SoH) and enhancing overall lifespan.

Completely chemistry agnostic, Dectravalve can optimise the performance of any EV battery – and future systems too. It is also incredibly cost-effective, bringing game-changing benefits for a fraction of the cost of developing an entirely new pack. Collectively, Dectravalve from Hydrohertz can help to transform EV useability, while also boosting residual values of used vehicles, and enhancing second-life potential of the battery pack at the end of the vehicle’s time on the road.

Martyn Talbot continued: “The Dectravalve solves a fundamental problem of EV battery thermal management systems – how to achieve true independent zone control of temperature without the complexity, weight, and energy waste of multiple valve arrays. Our innovation is elegantly simple: a single, digitally controlled unit that can manage four or more cooling zones separately. With Dectravalve, each cooling zone is completely independent, so coolant flows from the pump to the battery and back again in a specific loop. There are no unwanted, efficiency-sapping, leaks of warm coolant between zones.

“With Dectravalve, there is no ‘shared circuit’ where one overheated cell group could cause wider thermal contamination. This stops there being a thermal “domino effect” where hotspots quickly spread, and also ensures that each section of the battery receives exactly the cooling it needs. The result is a clean, controlled thermal environment right across the pack, with zero compromise or crossover.

“What makes this genuinely breakthrough technology is the precision it delivers. In our testing, we kept battery cells within just 2-3°C, which translates directly into faster charging, longer battery life, and, critically, enhanced safety. We've essentially

created a thermal management system which thinks and responds as quickly as possible – and one that is completely agnostic to cell chemistry too.”

Paul Arkesden, CEO of Hydrohertz, said: “The automotive industry has been waiting for battery technology to catch up with consumer expectations, but progress has been slow and expensive. A new chemistry can take a decade to develop and require billions in investment. What we've done is take a different approach – we've dramatically improved how existing batteries perform by perfecting the thermal management of them. “This is a cost-effective solution that delivers game-changing results: consistent 10-minute charging, longer range, extended battery life, and enhanced safety. For OEMs, this means better, more useable EVs now, without waiting for the next generation of battery technology. But when that technology does arrive, Dectravalve will optimise it too. The impact for both car makers and consumers is set to be transformative.”

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