The 5,700-Year Diamond Battery Turning Nuclear Waste Into Lasting Power

A Tiny Battery With a Lifetime Measured in Millennia

A battery measuring about 10 millimeters by 10 millimeters, with a thickness of up to 0.5 millimeters, offers an unusual answer to a familiar problem: how to keep a device running when replacing its power source is difficult or impossible. Developed by researchers at the University of Bristol and the UK Atomic Energy Authority (UKAEA), the carbon-14 diamond battery produces a continuous, tiny supply of electricity from radioactive decay.

The researchers unveiled their prototype in December 2024. Its defining feature is the 5,700-year half-life of carbon-14, the radioactive material at its heart. After that period, the material would supply about half its initial power through decay. The prospect is a source of energy that could keep working across generations, potentially for thousands of years.

Professor Tom Scott, Professor in Materials at the University of Bristol, leads the research team. His group has spent years investigating how radioactive materials can become useful energy sources. The prototype brings that work into a compact device designed for situations where small amounts of power, supplied reliably, matter more than high output.

The electricity comes at microwatt levels, far below the requirements of a smartphone or an electric vehicle. Medical implants, remote sensors and tracking equipment are among the proposed applications. For these devices, replacing a battery can require surgery, an expensive maintenance visit or access to somewhere people cannot easily reach.

The project also offers a possible use for material left behind by nuclear fission reactors. Carbon-14 recovered from reactor graphite can become part of a synthetic diamond battery, turning a radioactive waste material into an energy resource.

What the 5,700-Year Figure Means

Carbon-14 is familiar from archaeology, where its predictable decay helps scientists estimate the age of ancient organic material. A half-life describes the time required for half the radioactive atoms in a sample to decay. In this battery, that slow process supplies the energy used to generate electricity.

The 5,700-year figure therefore describes a gradual decline in the radioactive energy supply. After nearly six millennia, the battery would retain about half its initial power output from that process. The attraction is a steady source of very low power over a period far longer than the service life of conventional batteries.

Modern rechargeable batteries typically last between 500 and 1,000 charge cycles before substantial degradation. Solar panels depend on receiving sunlight. The diamond battery instead draws continuously on radioactive decay, with its energy source sealed inside the hardest known natural substance.

Researchers see this approach as especially valuable where maintenance is impossible and dependable operation is essential. Their development work stretches from an initial laboratory demonstration toward possible industrial uses:

• Early 2024: Beijing Betavolt New Energy Technology announced its competing BV100 nuclear battery, using nickel-63.
• During 2024: California company Infinity Power also entered the field with a nickel-63 coin cell.
• December 2024: The University of Bristol and UKAEA unveiled their carbon-14 diamond battery prototype.
• The coming decade: The Bristol project is focused on increasing production and improving power performance, while exploring applications with industrial and research partners.

How Diamond Converts Decay Into Electricity

Carbon-14 releases fast moving electrons as it decays. These emissions are called beta particles. The battery captures their energy using a process known as betavoltaics, which resembles the way a solar cell converts incoming light into electricity.

A solar panel receives energy from particles of light called photons. A betavoltaic device receives energy from radioactive decay instead. In the Bristol design, carbon-14 is embedded within layers of manufactured diamond. Diamond acts as a semiconductor, a material whose electrical properties allow the energy deposited by those particles to produce an electrical current.

The diamond also provides protection. Carbon-14 emits radiation with a short range, and the surrounding diamond absorbs the beta particles inside the device. During normal operation, the casing contains those emissions while the battery produces electricity.

Sarah Clark, Director of Tritium Fuel Cycle at UKAEA, described the intended combination of containment and continuous power:

Diamond batteries offer a safe, sustainable way to provide continuous microwatt levels of power. They are an emerging technology that use a manufactured diamond to safely encase small amounts of carbon-14.

The small size of the prototype helps explain its proposed uses. At approximately 10 millimeters square and no more than 0.5 millimeters thick, it is intended for compact equipment with modest energy needs. Its value lies in maintaining a small electrical supply for a long time.

Making a Resource From Reactor Graphite

The carbon-14 for these batteries comes from graphite blocks removed from nuclear fission reactors. The United Kingdom holds approximately 95,000 tonnes of this graphite, creating a substantial requirement for the storage and management of radioactive material over long periods.

Extracting carbon-14 from that graphite offers two potential benefits: reducing the burden associated with radioactive waste and creating a useful source of energy. The extracted material can be incorporated into synthetic diamond, where its decay supplies power inside a protective structure.

Engineers at UKAEA's Culham Campus built a specialized plasma deposition rig for producing the diamond layers. The manufacturing process, called plasma-enhanced chemical vapor deposition, uses a gaseous feedstock to grow diamond under controlled conditions. Precision matters because the structure must contain the radioactive material while capturing energy from its emissions.

UKAEA brought expertise developed through fusion research to the collaboration. Handling radioactive materials, working with plasma deposition and manufacturing specialized semiconductors are skills associated with research on tokamak reactors. Those capabilities helped support a project using material from fission reactors, which generate energy by splitting atoms.

Professor Neil Fox, Professor of Materials for Energy at the University of Bristol, described why the researchers chose diamond as the protective material:

Diamond is the hardest substance known to man; there is literally nothing we could use that could offer more protection.

One gram of carbon-14 can deliver 15 joules of electricity daily. That figure captures the central tradeoff: a small amount of energy delivered repeatedly over an exceptionally long period. At the end of a battery's functional life, it can be returned to its manufacturer for controlled recycling or disposal, with the carbon-14 kept encapsulated through its lifecycle.

Medical Devices Could Avoid Repeated Battery Changes

Medical implants are among the most promising proposed uses because replacing their batteries can mean another operation. Pacemakers, hearing aids and ocular devices are identified as possible applications for a source that supplies electricity continuously without routine recharging.

Traditional batteries in these kinds of medical devices can require replacement every five to ten years. When replacement involves surgery, patients face risks of infection and other complications, along with recovery time. A power source lasting throughout a patient's life could reduce the number of procedures and their associated healthcare costs.

Patients in remote regions could benefit particularly from longer intervals between interventions. Limited access to medical facilities makes repeated replacement procedures more difficult to arrange. A durable power supply would address one recurring maintenance need for suitable devices.

Medical adoption still requires extensive testing and regulatory approval. The battery's diamond containment is central to the proposed safety approach, while an implanted product must meet demanding requirements for reliable operation inside a person over decades.

The immediate development task is to match the battery's microwatt output to equipment able to use it. The researchers are exploring applications with partners; no date has been given for an approved medical product or a commercial carbon-14 battery launch.

Spacecraft, Tracking Tags and Remote Sensors

Space exploration presents a similar maintenance problem on a much greater scale. A spacecraft far from Earth cannot receive a routine battery replacement. Deep space probes and satellites can eventually lose contact as sunlight becomes insufficient for their solar panels or conventional batteries run down.

Voyager 1, the farthest human made object from Earth, relies on a traditional nuclear power source with a limited operating life. The carbon-14 approach offers the prospect of supplying suitable instruments or communications equipment with low levels of electricity for decades or centuries.

Radio frequency tags are another proposed application. These devices use radio signals to help identify or track equipment. Tags attached to spacecraft or payloads could potentially remain trackable for thousands of years, while active tags on Earth or in space could serve equipment for decades, reducing replacement costs and extending useful operation.

The battery can operate at temperatures from minus 60 degrees Celsius to plus 120 degrees Celsius without self-discharge. That operating range makes it a candidate for harsh environments where conventional power supplies can be difficult to maintain.

Arctic monitoring stations, sensors beneath the sea serving oil and gas infrastructure, and security equipment in inaccessible locations are among the terrestrial possibilities. Each shares a practical requirement: modest power consumption combined with long periods of unattended service.

The proposed uses put the technology's strengths into focus. A sensor taking measurements in a remote location has very different energy demands from an electric vehicle. For the sensor, avoiding maintenance visits over decades may matter more than increasing power output.

China, the United States and South Korea Pursue Alternatives

Beijing Betavolt New Energy Technology announced its BV100 battery in early 2024, using nickel-63 instead of carbon-14. The device measures 15 millimeters by 15 millimeters by 5 millimeters and produces 100 microwatts at 3 volts.

Betavolt's proposed operating life is 50 years. The company has also outlined plans to launch a version producing one watt later this year, with batteries connected in series intended to support consumer electronics. Its targeted applications include aerospace equipment, artificial intelligence equipment and micro-robots.

California company Infinity Power entered the field in 2024 with a nickel-63 coin cell, taking an approach similar to Betavolt's. Researchers at South Korea's Daegu Gyeongbuk Institute of Science and Technology have also experimented with betavoltaic cells using different radioisotopes, including isotopes of carbon and hydrogen.

Research teams across China, the United States and Europe are working toward commercial nuclear batteries. Their designs share the aim of reducing or removing the need for battery replacement, although the choice of radioactive material changes the expected service life and potential applications.

The comparison between Betavolt's stated 50-year operating life and carbon-14's 5,700-year half-life helps explain the different priorities. Nickel-63 designs target service measured in decades. The Bristol project focuses on exceptionally long duration applications, including medical devices and deep space equipment, where access for maintenance may be impossible.

Scott established Arkenlight as a commercial venture to develop industrial partnerships and assess markets for carbon-14 technology. The company provides a route for investigating how laboratory research might become products suited to particular customers.

Production Costs and Approval Shape the Next Stage

The gaseous feedstock used to create pure carbon-14 diamond costs approximately $46,000 per liter. That expense is a major challenge for increasing production and bringing the technology beyond a small number of specialized applications.

Manufacturing also requires specialized chemical vapor deposition reactors operating with a static flow, installed within facilities equipped to handle radioactive materials. Such requirements limit production capacity and make expansion more complicated than adding conventional battery assembly equipment.

Researchers are working toward greater production scale and better power performance over the coming decade. Lower manufacturing costs could widen the range of practical uses beyond specialized medical and aerospace equipment.

Regulators will also have a central role. Any device containing radioactive material requires extensive testing and oversight. A sealed diamond structure simplifies aspects of containment compared with other nuclear technologies, while approval still depends on demonstrating that a finished product meets the requirements for its intended use.

Public acceptance is another consideration, particularly for consumer products and medical implants. The word radioactive can cause concern even when the material is enclosed. Explaining how carbon-14 releases energy and how diamond contains its emissions will be part of introducing the technology to potential users.

Scott described the range of applications his team hopes to explore through cooperation with industry and other researchers:

Our micropower technology can support a whole range of important applications from space technologies and security devices through to medical implants. We're excited to be able to explore all of these possibilities, working with partners in industry and research, over the next few years. We want to use this technology for advancing the human race.

The next stage centers on turning that ambition into devices with useful power output, repeatable manufacturing and the necessary approvals. The prototype has demonstrated a route for converting radioactive material into electricity. Its proposed applications depend on making that route practical for equipment expected to work reliably for many years.

Key Points

• The University of Bristol and UKAEA unveiled their carbon-14 diamond battery prototype in December 2024.
• Carbon-14 has a half-life of 5,700 years, allowing an exceptionally slow decline in the energy supplied by radioactive decay.
• The compact battery produces continuous power at microwatt levels, suited to equipment with very low energy needs.
• Synthetic diamond converts energy from beta particles into electricity and contains the emissions during normal operation.
• Reactor graphite provides a potential source of carbon-14. The United Kingdom holds approximately 95,000 tonnes of this material.
• Proposed applications include medical implants, space equipment, radio frequency tags and sensors in remote or inaccessible locations.
• Betavolt and Infinity Power are pursuing nickel-63 designs, while researchers in South Korea are experimenting with several radioisotopes.
• Feedstock costing approximately $46,000 per liter, specialized manufacturing and regulatory approval remain central challenges for commercialization.