A battery that’s safer and cheaper than lithium-ion while offering comparable energy density? That sounds like a pipe dream. But such a battery is in fact in the works, using a chemistry of renewables to store over 220 W/kg. Singaporean startup Flint believes it has the formula for the most sustainable battery the world has ever seen, capable of replacing lithium for applications like EV power and grid storage. Maybe that is a dream. Or maybe it’s the revolutionary eco-optimized battery of the near-future.
A fully sustainable paper battery that can be recycled and dropped in compost at the end of its life cycle sounds too good to be true. It kicks off a major cynicism alert, and the questions flow like water through a burst dam.
Does it offer such low capacity as to be useless for anything outside a laboratory? No, Flint estimates energy density at 226 W/kg, which falls comfortably within the range of existing lithium tech.
Does it have a life cycle measured in hours rather than years? Nope, Flint says the rechargeable batteries will have a life cycle comparable to traditional battery technologies, unlike other single-use paper battery designs.
Will it prove impossible to scale from lab to mass production? Flint has conceived the battery with mass manufacturing in mind and is developing it from the ground up to work within existing lithium manufacturing systems and processes.
Does it seem like Flint has meticulously crafted answers to every pointed question a skeptic might make? Yes, we suppose it does. But that doesn’t mean we’re not hopeful its paper battery can materialize into a commercialized reality, even if it’s in some lesser form than what’s being proposed today.
Flint
Founded by a “team of scientists, technologists, designers and innovators,” Flint aims to take a direct shot at climate change with practical, scalable solutions. In fact, the company wasn’t initiated as a battery startup at all but developed organically from the innate desire to answer the question, “Why are the tools we depend on to power our lives so harmful to the planet?” Predictably, the focus on batteries came not long after digging for answers.
Company founder and CEO Carlo Charles and his team believe that the best solution won’t ever come from merely tweaking existing battery tech but from rethinking the entire system. And Flint’s battery chemistry reflects that – instead of just replacing an element or two, Flint is writing a completely new formula out of renewable and readily recyclable ingredients.
The company’s proprietary battery chemistry relies on cellulose, the structural plant material used to make paper, as the medium for ion transfer between the anode and cathode. Flint then replaces problematic non-renewables like cobalt and lithium with less environmentally impactful, easily recycled metals like zinc and manganese.
Flint
The cellulose also underpins a more versatile, pliable battery structure, allowing Flint to make batteries in different forms. Rather than having to design a vehicle or device around a battery brick, builders could theoretically structure the battery to fit into the optimal space in the vehicle or gadget.
We’ve seen over the years that declaring the next great battery technology on paper and backing the claim up with a few lab milestones is the easy part. The big lifting comes in wresting that next great technology from the white coats and putting it on production lines, and doing so in a time period measured in units smaller than decades. That’s why Flint has been working to create its battery in a form that can be built via the same manufacturing processes currently in use for lithium batteries.
As to cost, the company believes it can eventually build its batteries for roughly US$50/kWh, less than half the average 2024 cost of lithium-ion. That’s thanks largely to the use of those abundantly available sustainable materials and metals that are easier and less costly to mine than traditional battery metals.
Finally, if you still have a little bit of credulity left to offer, Flint claims its cellulose-based battery is significantly safer and more stable than lithium, virtually eliminating the chance of catastrophic fire. The water-based electrolytes are stable and non-toxic and formulated to prevent overheating, sparking and explosion.
Flint
Flint even says its batteries can work for a short period of time when lit with an open flame or damaged, ultimately degrading without causing a catastrophic event. And because of that same stability and non-toxic design, the innards can be removed from their vacuum-sealed casing, the metals extracted and recycled, and the remainder left to degrade naturally in the soil, without environmental harm.
Okay, that’s quite an overflowing mouthful of potential pie-in-the-sky promise to chew on all at once. Flint recognizes it has a serious hill to climb in fulfilling the huge objectives its laid out for itself, but it remains steadfast in its mission. It closed a $2-million seed funding round in late 2024 and plans to purpose that money toward commercial expansion, intellectual property development, and a 2025 pilot production program.
We certainly hope this isn’t the last we hear from Flint, and we don’t believe it will be. Because even if it only comes through on a part of that scroll of breakthroughs and advantages, it will still have a very special product to market.
Source: Flint
