Nyobolt EV Prototype Sets Benchmark for Ultra-Fast Charging and Efficiency

Nyobolt has advanced its high-power density, fast-charging battery technology from the lab to practical application with the debut of its first operational EV prototype.

Collaborating with CALLUM, the design and engineering of the Nyobolt EV aim to validate the performance of the company's batteries in a high-performance setting, while also demonstrating to car manufacturers how this technology can eliminate inconvenient charging downtimes for customers.

Established in 2019 and based in Cambridge, Nyobolt has developed patented materials for its carbon and metal oxide anodes, along with an innovative low impedance cell design, integrated power electronics, and sophisticated software controls. These advancements have resulted in power-dense battery and charging systems tailored to the electrification needs of high-uptime industrial and automotive sectors, including heavy-duty off-highway trucks, EVs, robotics, and consumer devices that require high power and rapid recharge cycles

Recent in-vehicle testing using robust 350kW (800V) DC fast chargers confirmed that Nyobolt EV’s 50Ah 35kWh battery could be charged from 10% to 80% in just four minutes and 37 seconds. A full charge grants the prototype a range of 155 WLTP miles, which is twice as fast as most of the quickest charging vehicles currently available. Notably, the initial four minutes of charging at a constant 500A current deliver 120 miles of range.

Longer lasting performance batteries offer over 600,000-miles life

Nyobolt's technology addresses the common issue of degradation associated with supercharging lithium-ion batteries. Its 24.5Ah cells have demonstrated impressive durability, completing over 4,000 full Depth of Discharge (DoD) fast charge cycles. This performance translates to more than 600,000 miles in the Nyobolt EV pack, while maintaining over 80% of the battery's capacity. This endurance far exceeds the warranties offered for much larger EV batteries currently on the market.

Independent testing by OEMs has validated that Nyobolt's 2.6Ah cells can endure over 4,400 cycles with a 12C charge and 1C discharge at 23°C. Importantly, the internal resistance of the cells increases by only 50% after 4,400 five-minute charge cycles. This rate of increase is below the industry’s end-of-life threshold for EV cells, which is typically twice the initial resistance value.

“Despite some OEMs showing fast charge times in the region of 15 minutes, a closer inspection reveals the charge is usually across a limited SOC region specifically chosen to limit the amount of life taken out of the cell; for instance, between 20-80%,” says Nyobolt’s co-founder and CEO, Dr Sai Shivareddy. “Typically, the charge profile will only hold these peak charge levels for a short amount of the charge time. Nyobolt’s low impedance cells ensure we can offer sustainability, stretching out the battery’s usable life for up to 600,000 miles in the case of our technology demonstrator.”

Enabling lighter EVs for the enthusiast

The 35kWh battery pack in the Nyobolt EV prototype not only extends range rapidly but also offers significant advantages in its compact design. This smaller battery pack benefits both car manufacturers and drivers by facilitating the creation of energy-efficient electric vehicles that are more affordable to purchase and operate, while also requiring fewer resources for production.

The choice of a sports car, weighing in at just 1,250kg, as the Nyobolt EV prototype is deliberate. It demonstrates that Nyobolt's technology can support the automotive industry in producing lighter, more agile sports cars with superior handling, marking a return to high-performance driving experiences.

“We can enable OEMs to build excitement back into the segment, which is literally weighed down by legacy battery technology currently,” says Shane Davies, Nyobolt’s director of vehicle battery systems.

“Our Nyobolt EV demonstrates the efficiency gains facilitated by our fast-charging, longer-life battery technology, enabling capacity to be right-sized while still delivering the required performance,” adds Davies. “Nyobolt is removing the obstacle of slow and inconvenient charging, making electrification appealing and accessible to those who don’t have the time for lengthy charging times or space for a home charger.”

Scalable battery production already planned

While the primary focus of the Nyobolt EV is to showcase and test its advanced battery technology, CALLUM’s engineering team has designed it for potential low-volume production, suitable for both road and track use. Nyobolt's battery assembly plans are well-developed, with the capability to commence low-volume production within a year, scaling up to 1,000 packs by 2025. The company’s adaptable manufacturing model supports the production of up to two million cells annually. Furthermore, Nyobolt’s batteries will comply with the EU's Battery Regulation requirements once they enter production.

Enhancing Existing EVs

The architecture of the Nyobolt EV also demonstrates its potential for retrofitting existing EV platforms, significantly improving charge times and battery life cycles. The battery modules in the Nyobolt EV are cooled using cold plates with a water/glycol mix, an AC compressor, and condenser, along with a battery chiller compatible with other high-performance vehicles. This results in a near-standard module and battery pack. Thanks to its ultra-low impedance cell chemistry, the battery generates limited heat – no more than 60°C during fast charging or high-performance driving.

Pioneering Battery Chemistry from the UK

Nyobolt's technology is the culmination of a decade of battery research led by University of Cambridge scientists Professor Clare Grey CBE and Dr Sai Shivareddy, who previously developed innovative supercapacitors. The key to Nyobolt’s ability to offer ultra-fast charging without compromising battery life lies in its low impedance cells, which generate less heat and facilitate high-power charging. These cells feature an anode material that allows for a rapid transfer of electrons between the anode and cathode, enhancing performance.

Broadening Horizons Beyond Automotive

Nyobolt has garnered strong interest, engaging with eight additional vehicle OEMs about adopting its technology. Beyond automotive applications, Nyobolt’s fast-charging technology is set to be introduced in the robotics sector this year. The technology is also being explored for other applications requiring low downtime and high productivity, such as heavy-duty commercial vehicles.

“Our extensive research here in the UK and US has unlocked a novel battery technology that is ready and scalable right now,” concludes Shivareddy. “We are enabling the electrification of new products and services currently considered inviable or impossible. Creating real-world demonstrators, such as the Nyobolt EV, underlines both our readiness and commitment to making the industries see change is possible.”