The Max Planck Institute for Medical Research has produced batene fleece, a fine metal fleece, to act as current collectors in batteries, making them safer and more energy dense. Its Batene GmbH spinoff, backed by €10 million ($10.02 million) of seed funding, is now bringing the tech to market.

A new approach developed by researchers at the Max Planck Institute could potentially pave the way for the transition from 2D foil current collectors, which are used in today’s lithium-ion batteries, to fleece current collectors. The innovation could drive the emergence of a new generation of rechargeable batteries with high energy density, faster charging rates, prolonged runtimes, and longer lifespans.

At the heart of the team's innovation is a process developed by Joachim Spatz, the director at the Max Planck Institute for Medical Research. The process results in very fine metallic fibers, which can be used to make thicker battery cells.

The metallic fibers, which have good electrical conductivity, are then processed into a dense, conductive metal mesh and filled with the active material of the anode or cathode. Such electrodes make it possible to increase the thickness of battery cells to more than 2 mm, or 10 times that of cells commonly used today.

The active material, which is important for energy storage, currently accounts for just 60% of lithium-ion battery weight. But the new design developed at the Max Planck Institute for Medical Research reduces the metal content and increases the active material proportion of the total battery weight.

The metal meshes have a significantly larger surface area than conventional current collectors, so the batteries with such current collectors can be charged and discharged much faster. In addition, the metal mesh is said to make the lithium-ion batteries safer by reducing the electrical resistance of the electrodes and increasing their mechanical stability, eliminating unfavorable hotspots in heat generation, as well as electrical and mechanical stress.

The researchers said the new batteries are resource efficient due to “significantly reduced material consumption and an extremely energy-saving manufacturing process.” The millimeter-thick electrodes are said to translate into significantly extended battery life and up to 30% less material costs per kilowatt-hour.

The active material and the batene fleece, as the current collector, are highly elastic and capable of adapting to volume changes during charging and discharging. This reportedly prevents the premature aging of the battery.

While the innovation can function as a drop-in technology for existing production lines, according to the researchers, it is not limited to the lithium-ion batteries of today. The ultra-fine metal mesh electrodes are also said to have great potential for other battery chemistries, such as lithium metal solid-state batteries or sodium-ion batteries.

Batene GmbH, a newly established spinoff of the institute, has licensed the technology through the Max Planck Society’s central technology transfer company, Max Planck Innovation, and is now marketing it. It has already secured initial funding of €10 million.

The startup has also exclusively licensed the corresponding rights to develop and market the technologies. Following successful demonstrators, it is now ready to build up a larger production capacity for electrodes made of metal fleece, to further develop the technology.

As cyber risks rise with increasing deployment of distributed energy resources, the government and industry are defining the steps needed to ensure cybersecurity.

The U.S. Department of Energy (DOE) is working with four national laboratories and industry participants to propose cybersecurity requirements for distributed energy resources, said Guohui Yuan, a program manager with DOE’s Solar Energy Technologies Office, on a webinar. The requirements could involve standards, best practices, and procedures for testing and analysis.

The DOE initiative, which also encompasses cybersecurity for large-scale solar, is known as “Securing Solar for the Grid.” A DOE report on the topic calls for the distributed energy resource (DER) industry to engage in such discussions.

As deployment of rooftop solar, batteries and other DERs increases, the potential damage from a cyberattack on DERs also increases, says DOE’s report. DERs now total 90 GW of capacity in the U.S., and are expected to grow to 380 GW by 2025, the report said.

Past cyberattacks on renewable generation indicate the risk of attacks on DERs, said Meg Egan, a control systems cybersecurity analyst with the Idaho National Laboratory, on the webinar. Three nations are capable of cyberattacks, as are criminal groups, she said, noting 10 cyberattacks on large-scale renewable generators or renewables firms since 2019 worldwide.

In two potential scenarios of a cyber attack, an attacker could use ransomware to take control of multiple DERs, or could use a supply chain attack on an aggregator, or on another party that sends directions or updates to DERs, to influence the operation of the DERs.

In two other scenarios, a “botnet” could infect enough DERs with malware to enable the attacker to create unanticipated power swings on the grid, or a “worm” could spread from one DER to a higher-level distributed energy resource management (DERM) system, which could then send a false command to many DERs and instigate power instability.

To be resilient against attacks, DER systems “should be designed, built and operated by means of an enforced zero-trust model,” where data and commands are validated “using cryptographically secure mechanisms informed by standards, testing and vulnerability assessment,” said the DOE report. A key step toward that goal, the report said, is to publish and implement DER cybersecurity guidelines being developed as IEEE Standard 1547.3, once that standard is finalized.

DERs are increasingly participating in stabilizing regional grids and ensuring reliability, said the DOE report. This role of DERs is the result of both the smart inverter standard known as IEEE 1547-2018, and the Federal Energy Regulatory Commission (FERC) Order 2222 that opens wholesale markets to aggregated DERs. Yet the two-way capabilities that enable DERs to help support the grid also open opportunities for cyberattacks, the report said.

Guohui Yuan of DOE said that both states and FERC will have a role in adopting DER cybersecurity standards.

The DOE report is titled “Cybersecurity considerations for distributed energy resources on the U.S. electric grid.” DOE said it would post the webinar slides on the report’s landing page.