Here's the battery tech that gives Digit 5 a 10:1 work-to-charge ratio
One of the key features of Digit 5 from Agility Robotics, coming next year, is the amount of time it can spend on-task. This humanoid robot will do 90 minutes of work and need only 9 minutes to recharge.
But how?
That ratio, baked into Agility Robotics' new Digit 5 humanoid, is the result of a partnership with Nyobolt, the Cambridge battery unicorn, and it is a huge step up from from Digit 4's 2:1 ratio: 5X the operational efficiency in a single generation.
As reported by The Information, Nyobolt has landed its second robotics contract, this time with Agility Robotics. (The first was with Symbotic for its SymBot warehouse robots.) The same battery technology is now heading into a full bipedal humanoid platform destined for manufacturing and logistics deployments starting in the first half of 2027.
What Nyobolt actually built
Nyobolt is a spin-out from the Yusuf Hamied Department of Chemistry at the University of Cambridge, founded in 2019 by Professor Dame Clare Grey and CEO Dr. Sai Shivareddy. The core innovation is a niobium tungsten oxide anode whose crystal structure allows up to 100 times more lithium-ion mobility than graphite.
That means batteries can charge at rates that would destroy a conventional cell without triggering the degradation, heat buildup, or fire risk that typically accompanies fast charging.
And the performance numbers are striking.
Nyobolt's cells charge to 80 percent in under 5 minutes. Cycle life is at least 10 times longer than conventional lithium-ion, and energy density is 20 times that of supercapacitors.
In May 2026, the company closed Nyobolt's $60M Series C at a $1 billion valuation, led by Symbotic, reaching unicorn status just as demand for its technology was taking off in robotics and AI data centers.
What it means for Digit 5
Agility Robotics' Digit 5, the latest generation of its humanoid robot, targets more than 20 hours of productive work in a 24-hour day.
"Digit 5 will deliver more than 20 hours of productive work in a 24-hour day, more than two full shifts," says Daniel Diez, Chief Business Officer at Agility. "That's the kind of gain that materially improves the value customers get from Digit."
For a robot that costs in the range of $30,000 to $50,000, utilization is everything.
The difference between 2:1 and 10:1 run-to-charge is the difference between a robot that spends a third of its time plugged in and one that is almost always working.
The Nyobolt battery package delivers more power from a smaller, lighter pack. That weight reduction also matters for a bipedal robot where every kilogram affects balance, gait efficiency, and joint wear.
The first contract: Symbotic's SymBot
Nyobolt's first commercial robotics win was with Symbotic's SymBot robots, announced September 2025.
For those warehouse mobile robots, the Nyobolt battery provided 6 times more energy capacity and 40 percent lower weight compared to the ultracapacitors previously used, with a cycle life at least 10 times that of conventional lithium-ion. The batteries also proved retrofit-compatible with earlier SymBot generations and backward-compatible with existing charging infrastructure. Symbotic subsequently led Nyobolt's Series C round, making the relationship both commercial and financial.
Agility is the second. Expect more.
Why this matters beyond Agility
Battery performance is one of the major constraints in humanoid robotics.
Every company in the space faces the same arithmetic: a robot that spends significant time charging is a robot generating less value. Tesla Optimus, Figure, Unitree, Boston Dynamics Atlas, and every other humanoid platform needs to solve this problem at scale.
Nyobolt's approach, rooted in a decade of academic research and now backed by Symbotic's commercial validation, positions it as a potential standard-setter for robotic power systems. The combination of fast charging, long cycle life, and high energy density addresses the three variables that matter most for continuous industrial operation.
If Nyobolt's numbers hold in production conditions, they'll set a new benchmark. And they'll be a preferred source for more than just 2 robot companies.
Sources
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I tell stories with data and build startups. I've raised angel and VC funds, led software companies and startups, and chronicled the rise of the mobile economy. Currently I write for Forbes, host several podcasts, and am starting up HumanoidMegaHub. I was TUNE's mobile economist and Singular's VP of Insights, built the research team at VentureBeat, and managed teams creating software for partners like Intel and Disney. In past lives I built websites, e-learning platforms, and mobile apps, and, a long time ago, was named to Folio's top 100 of the media industry's "most innovative entrepreneurs and market shaker-uppers.”