A California-based startup called NDB Inc. says it is poised to offer a nanodiamond-based alternative to current battery technology that will be more efficient and sustainable for electric aircraft. On August 25, the company announced that it has completed proof-of-concept tests on its self-charging nanodiamond battery, achieving what it claims is a breakthrough 40 percent charge, compared with charge collection efficiency rates of just 15 percent with commercial diamonds.
NDB also announced that it has signed up two undisclosed launch customers for a beta version of the technology. It says that one is a leading aerospace, defense, and security manufacturer, and the other is a Europe-based leader in nuclear fuel cycle products. Electric aircraft and vehicles are among the anticipated early adopters of the technology.
The privately-owned company is now working on the first commercial prototype of its nanodiamond battery and aims to have this available before the end of 2020. It says that the proprietary self-charging process will provide a charge for the full lifetime of any device or machine, with up to 28,000 years of battery life.
The power source for the nanodiamond battery is intermediate- and high-level isotopes that a shielded for safety by multiple levels of synthetic diamond. According to NDB, the energy is absorbed in the diamond through a process called inelastic scattering, which is used to generate electricity.
Since the battery is self-charging, it requires only exposure to natural air, and any excess charge can be stored in capacitors, super-capacitors, and secondary cells. It does not require any external power source, and it incorporates a DC-to-DC converter to control the current.
“A 40 percent [charge] efficiency has never previously been achieved due to [previous] material choices, and our proprietary technology has achieved this breakthrough in efficiency,” NDB’s CEO and cofounder Nima Golsharifi told FutureFlight. “What we have achieved competes with what is available from traditional fossil fuels in terms of energy density, and it is not climate- or light-dependent [like other sustainable power sources].
A 40 percent charge rate means that 40 percent of the charge generated by the radio isotopes was collected using the diamond technology. By comparison, solar power cells typically have a charge collection efficiency rate of around 15 to 20 percent.
NDB believes that it will be able to achieve a 90 percent rate of charge. This further progress could result in smaller, lighter batteries.
The company says it is now engaged in research work aimed at supporting the use of nanodiamond batteries to power eVTOL aircraft. The work is supported by the U.S. government’s defense and energy departments.
According to Golsharifi, the batteries will provide sufficient power to support cruise flight for unmanned aircraft. The company expects to build a commercial prototype of the battery within the next three years.
The proof-of-concept testing was conducted at the Lawrence Livermore National Laboratory in the U.S. and at the Cavendish Laboratory at the UK’s Cambridge University. The experiments were led by professor Sir Michael Pepper, a pioneer in semiconductors and winner of the Institute of Physics Isaac Newton Medal.