Why We Love Second Life Batteries
I'll admit it – at OnBio we’re obsessed with second-life batteries. There's something particularly satisfying about the battery packs we source from unwanted Tesla cars.
GOLD STANDARD EV CAR BATTERIES
A standard Tesla car battery is a battery pack comprising of 16 modules, each made from 444 battery cells known as 18650s. These big, AA-shaped batteries were specifically developed by Panasonic in collaboration with Tesla. Being designed for the EV market, they have an impressive volumetric energy density which is still excellent even by today’s standards. Each module has its own sophisticated liquid cooling system meaning all cells are kept at a constant temperature and by avoiding temperature extremes the batteries have much longer life expectancies compared to many rival EV car manufacturers. This all means Tesla second-life batteries are absolutely perfect for our portable batteries. While we use 2 modules (888 cells) to make our Orb10s, a staggering 4 whole Tesla car packs (28,416 cells) are used to make our Orb300s.
IN THE EARLY DAYS
When we first started exploring second life lithium batteries, I wondered if we were making the right choice. Would they be reliable enough? Safe enough? How long would they last and could we ever source enough of them? It turns out these concerns were entirely unfounded. Every battery we use has passed rigorous safety testing and there turns out to be a plentiful supply of battery packs still retaining 90% of their original capacity – more than adequate for our applications, and essentially as good as new.
REPURPOSING SIMPLY MAKES SENSE
The environmental case for second life batteries is compelling. Compared to manufacturing new batteries, reusing existing cells can slash greenhouse gas emissions by up to 77%*. When you consider that making a new battery produces substantial CO2 emissions, giving these perfectly good modules a new purpose seems like common sense. We're also reducing the demand for lithium, cobalt, and nickel – materials that require environmentally destructive mining operations to extract.
The Orb300 getting ready for a night shoot on the Millenium Bridge
LONG LASTING
What really excites me is the potential longevity of our second-life batteries. A recent Edinburgh University study* found that these batteries can work in second-life applications for an additional 7-10 years, pushing their total operational life up to 20 years. That's two decades of service from a single battery pack. It’s too early to know for certain, but this is still very encouraging news.
THE CIRCULAR ECONOMY
When our batteries finally do reach the end of their useful life, they're 98% recyclable. We had a few that had water damage and were beginning to rust, so we sent them to Recyclus Group, who operate the UK's first industrial-scale lithium-ion battery recycling facility in Wolverhampton. Recyclus are able to recycle any type of lithium battery using their giant shredding machine that sorts the battery components ready to reuse. The shredded materials go straight back into manufacturing the next generation of EV batteries – a genuine circular economy in action.
A BRIGHT FUTURE IN STore
The projections for 2040 are staggering. Under the right conditions, recycled materials from retired EV batteries could supply 60% of global cobalt needs, 53% of lithium requirements, 57% of manganese demand, and 53% of nickel requirements. That's not incremental change – it's a fundamental transformation of how we think about battery ecosystems.*
For us, second life batteries aren't just a practical choice. They're proof that smart design and circular thinking can deliver both performance and sustainability. And yes, we only have eyes for those beautiful Tesla modules.
The Orb10 recently used during the making Bard Pitt’s F1 movie
* All facts taken from a 2025 a University of Edinburgh research paper entitled; A Perspective on the Challenges and Prospects of Realising the Second Life of Retired EV Batteries.