🌱 What if you could just bury your used batteries in the garden?
In about 6 weeks, they'd naturally decompose into the soil. No toxic waste, no recycling headaches, no fire hazards. This isn't science fiction—it's happening right now. A Singapore startup called Flint has started mass-producing "paper batteries" that could revolutionize how we think about energy storage.
Who Is Flint? A Young Founder's Mission to Reinvent Batteries
Flint is a Singapore-based deep tech company founded by Carlo Charles, who was named to Forbes' "30 under 30 Asia 2025" in the Industry, Manufacturing & Energy category. The company first previewed its technology at a TechCrunch event in San Francisco in late 2023, immediately attracting attention from the tech industry.
In December 2024, Flint raised $2 million in seed funding from angel investors spanning nine countries, including France, Germany, Hong Kong, India, Singapore, Sweden, Switzerland, the UK, and the US. AI-focused venture capital firm Hatcher+ also participated in the round.
From CES Award to Mass Production
Flint's paper battery technology received the "Best of CES Sustainability Award" at CES 2025 in January, recognizing its innovative approach to safer, lower-carbon energy storage.
On January 2, 2026, the company officially announced that production had begun at its new 8,000+ square foot facility in Singapore. This marks a significant milestone—the transition from laboratory prototypes to manufactured cells ready for real-world deployment.
"Reinventing batteries isn't only about chemistry, it's about building something you can manufacture," said Charles. "Entering production is a turning point because it means our paper batteries can move beyond prototypes and into real devices, at real volumes, with quality controls that customers can validate."
The Science Behind the Paper Battery
Materials and Structure
Flint's battery technology uses cellulose—the natural polymer that forms plant cell walls—as its core material. Unlike traditional batteries, every major component incorporates this plant-derived substance:
- Anode: Zinc
- Cathode: Manganese
- Electrolyte: Water-based solution such as Hydrogel
- Separator: Cellulose paper
Crucially, the battery contains no lithium, cobalt, nickel, or PFAS (per- and polyfluoroalkyl substances, often called "forever chemicals")—materials that have raised significant environmental and health concerns.
Safety Performance
Because the battery uses water-based electrolytes, the risk of fire or explosion is dramatically lower than conventional lithium-ion batteries. In Flint's demonstrations, the battery continued operating even when bent, punctured, or exposed to an open flame—with no leaks or explosions. This damage-tolerant design represents a fundamental shift in battery safety.
Environmental Impact
When disposed of, Flint's paper batteries can be buried in soil, where they biodegrade within approximately 6 weeks. The decomposition process leaves no harmful residues. While some components like plastic parts still require traditional recycling, about 80% of the battery naturally breaks down.
Cost Advantage
According to Flint, their paper batteries cost roughly half as much per kWh compared to lithium-ion batteries. The manufacturing process is also designed to integrate seamlessly with existing lithium-ion production lines, enabling rapid industrial adoption without requiring entirely new facilities.
Product Lineup: From AA Batteries to Ultra-Thin Pouches
At CES 2026, Flint showcased products in familiar formats that consumers already know.
AA and AAA Format Batteries
Standard-sized batteries made from renewable and sustainable materials. Expected lifespan is comparable to conventional alkaline batteries, with market release planned for later in 2026. At the CES booth, Flint demonstrated these batteries powering a toy train running on tracks.
Ultra-Thin Pouch Cells
Available in 1.5V and 3V configurations with 80mAh capacity. These cells are remarkably thin—just a few strands of hair thick—and flexible enough to bend. They're also rechargeable.
This flexibility could enable entirely new product designs. As Flint envisions: smartphones that fold more seamlessly, or EVs with more flexible battery placement creating roomier interiors.
Partner Companies and Applications
Flint has already initiated pilot programs with several global brands:
Confirmed Partners
- Logitech: Selected Flint as a winner of their Future Positive Technology Challenge 2025
- Amazon Devices: Exploring integration into handheld devices like Kindle and Fire TV
- Nimble: Already using Flint batteries in their tracking-enabled luggage tags for Apple accessories
- Dassault Systèmes: Providing support through their 3DEXPERIENCE Lab program
Target Applications
Initially, low-power devices are the primary focus: IoT sensors, wearable devices, remote controls, and tracking tags. Future applications could extend to home energy storage systems, medical devices, EVs, and even satellites or spacecraft.
Future Plans: European Expansion and Solid-State Development
Flint's ambitions extend far beyond its Singapore factory.
The company is in active discussions with one of the world's largest contract manufacturers to expand manufacturing capacity in Europe, with plans to diversify its supply chain. Charles explained: "Starting production in Singapore was an intentional choice. It shows the world that there's a credible path to making batteries without relying on the same centralized lithium supply chains the industry has depended on for decades."
In parallel, Flint is developing a solid-state derivative of its cellulose-based chemistry, targeting higher-density rechargeable applications. This next-generation technology aims to address markets currently dominated by lead-acid batteries and other legacy energy storage systems. Production plans include building a factory in Europe capable of producing 300 million batteries annually.
Breaking Free from Lithium Dependency
Modern society is deeply dependent on lithium-ion batteries. Smartphones, laptops, e-bikes, electric vehicles—countless devices that power our daily lives rely on lithium chemistry.
However, lithium mining has caused water depletion in South America's Atacama Desert, while cobalt extraction has been linked to child labor issues in Africa. According to Flint, if battery demand continues growing at current rates, raw materials could face shortages by 2030.
Paper batteries offer one answer to these structural problems. Cellulose is the most abundant organic polymer on Earth, available from plants worldwide. Flint currently sources cellulose from local Singapore plants but envisions future production using regional plant materials—including invasive species that are often considered ecological nuisances—creating locally-sourced manufacturing models.
Limitations and Challenges
In the interest of balance, it's important to acknowledge the current limitations of paper battery technology.
Energy Density: Compared to lithium-ion batteries, paper batteries have lower energy density, requiring larger volumes to store the same amount of power. Significant technical breakthroughs are still needed before they could power long-range EVs from manufacturers like Tesla or BMW.
Limited Applications: For now, low-power devices remain the focus. High-output applications aren't suitable targets. This positions paper batteries not as a "complete replacement for lithium-ion" but rather as an "alternative where lithium-ion is overkill."
Unproven Track Record: With mass production just beginning, long-term durability and performance stability in real-world conditions still require verification.
Conclusion: A New Option for the Battery Conundrum
Flint's paper batteries represent a simple yet powerful proposal addressing the environmental, safety, and resource challenges facing the battery industry. While they won't replace all lithium-ion batteries, they prompt us to ask: "Do we really need lithium for everything?"
Battery recycling rates remain low in many countries, and disposal of used batteries is an everyday environmental issue. If batteries that return to the earth become widespread, our very concept of "throwing away" could transform.
How does your country handle battery disposal and recycling? Would you be interested in trying batteries that decompose into soil? We'd love to hear your perspective.
References
- https://www.flintlabs.com/blog/flints-paper-batteries-are-here
- https://www.prnewswire.com/news-releases/flints-paper-batteries-are-here-now-in-production-now-available-302651613.html
- https://eetimes.itmedia.co.jp/ee/articles/2601/23/news084.html
- https://www.gizmodo.jp/2026/01/flint-paper-battery-1.html
- https://cleantechnica.com/2026/01/02/one-step-closer-to-the-compostable-ev-battery-of-the-future/
- https://www.techspot.com/news/110870-paper-batteries-made-plants-want-replace-aa-aaa.html
Reactions in Japan
I've been following this for a while, and it's finally in mass production. At CES 2025, I thought 'just another lab project that'll go nowhere.' Flint really delivered on their promises.
Looking at this objectively as an industry insider, 80mAh limits the applications significantly. Fine for IoT tags or remotes, but nowhere near smartphone territory. That said, do we really need lithium for those limited uses? Honestly, no.
Smart move releasing in AA/AAA format. The approach of keeping the standard form factor while making the internals eco-friendly lowers the barrier for consumers. Would love to review the actual product.
It says it decomposes in 6 weeks, but is it actually safe to bury in your garden? What about zinc and manganese leaching into the soil? I want to know if that's been fully verified.
I always felt guilty throwing away batteries from my kids' toys. We change batteries weekly for things like Plarail trains... If the cost is comparable, I'm definitely switching!
No cobalt or nickel is huge from a supply chain perspective. Not many people know about the cobalt mining issues in Congo, but the child labor situation is truly terrible.
Low energy density means it's just 'a battery with limited uses.' Can't replace lithium. Well, maybe it's fine for remote controls.
I want to read the papers. Has the durability of the cellulose separator and stability of the aqueous electrolyte been academically verified? Can't judge from just press releases.
Battery stockpiling at evacuation shelters is always a concern. Considering leak and fire risks. If this is safe, it might be ideal for emergency reserves. Wonder about the long-term storage capability.
As someone who wants to minimize possessions, I love the concept of 'returns to the earth after use.' Battery disposal is such a hassle, so this convenience is revolutionary.
The fact that it works even when punctured or torched is actually great for Arduino and electronics projects where you handle things roughly. I was scared to touch LiPos before.
Partnering with Amazon probably means it's for Kindle. We'd like to carry it too, but who's going to be the Japanese distributor? No information coming in at all.
Being able to write 'adopted biodegradable batteries' in corporate SDGs reports is strong marketing. Can also appeal to ESG investors.
Wait, is it okay to bury this in farmland? Won't it affect organic JAS certification? If we need soil analysis, that's a hassle...
2 million seed, CES award, mass production in a year. This speed is incredible. Japanese deep tech doesn't have this kind of breakthrough momentum.
Good news, but again from overseas... What are Japanese companies doing? I wish Panasonic would develop something like this.
There are situations in mountainous areas where you can't carry out trash, so batteries you can bury are welcome. But I want more info on whether there's truly no negative impact on natural environments.
Zinc-manganese system. Similar composition to old manganese dry cells, but the cellulose separator is key. Would love to cover this topic in class.
Finally, a CES sustainability award winner that actually made it to production. Every year we see inventions that end with 'cool but impossible to scale,' so I'm rooting for Flint. Will be first in line when the AA batteries come out.
In the Netherlands we have battery collection boxes at supermarkets, but honestly not many people use them. If you can just bury them, a 0% collection rate wouldn't be an environmental problem. A paradigm shift.
Curious how CATL and BYD view this technology. Chinese battery companies dominate global market share, but they must recognize the risks of lithium dependency. Will they acquire or develop their own?
Worried about how paper-based batteries would hold up in Ireland's damp climate. Wouldn't they be vulnerable to humidity? Guess it depends on the sealed packaging.
Chile is a major lithium producer, but the Atacama Desert water issue is serious. As a local, I have mixed feelings. I welcome alternative technologies, but I also think about the impact on our economy.
In rural India, battery recycling infrastructure is almost non-existent. Many end up thrown into rivers. If biodegradable batteries spread, we could reduce groundwater contamination. Depends on the price though.
Wonder if it complies with Germany's strict battery regulations (BattG). Even if biodegradable, certification is needed for sales. I think EU market entry has high hurdles.
Sweden is aiming for carbon neutral by 2030. If this technology could be used for home storage batteries, combined with renewables it would be even cleaner. What if they partnered with Northvolt?
In Nigeria, with unstable power, everyone uses dry cell batteries for flashlights and radios. Cheap and safe batteries could change lives. Hope they come to the African market.
Honestly, the energy density is too low to be practical. Good marketing, but technically I wouldn't call it a breakthrough. Feels overhyped to me.
In France, EV adoption is progressing, but we still use dry cells for remotes and toys. Making this 'invisible battery consumption' eco-friendly is a good approach.
I'm Japanese living in Singapore. I live near Flint's factory, but it's not really talked about locally. Strange that foreign media covers it more thoroughly.
Waste management is a challenge in Brazil's Amazon region. Some people even burn batteries. If they can be buried, I'd like to spread this along with environmental education.
Interesting to see how Samsung SDI and LG Chem respond. If paper batteries succeed in niche markets, they'll probably enter too. M&A for technology acquisition is possible.
My grandmother in Poland hoards batteries in drawers for years because she doesn't know how to dispose of them. How easy would it be if I could just say 'bury them in the garden.'
In Dubai's heat, lithium-ion batteries degrade quickly. Would water-based electrolytes be more heat resistant? I'd like to see test results from desert regions.
Mexico's e-waste problem is serious. Cheap Chinese batteries are being discarded en masse. If biodegradable batteries are available at the same price point, things could change.
Living in remote Australia, battery disposal is a real problem. The nearest collection point is over 200km away. If this becomes practical, life would be easier.