Silbat silicon batteries guarantee uninterrupted power supply for 14 days

Silbat is a Spanish startup developing a long-duration energy storage (LDES) technology based on silicon. The company’s battery technology stores electricity as latent heat in molten silicon, using low-cost, widely available metallic-grade silicon. Silicon has the second-highest latent heat of fusion of any element, after the much rarer boron. In Silbat’s design, metallic silicon is held in a refractory container within a thermally insulated crucible. Electricity is converted into thermal energy through resistive (Joule) heating, and when the temperature reaches 1,410 °C, the silicon begins to melt. The battery is fully charged once the silicon is completely molten.

Silbat recently announced to pv magazine the launch of the Research and Analysis of Long-Duration Energy Storage for Operational Resilience in Critical Military Infrastructure (ARMIC) project. The initiative aims to support resilient and self-sufficient energy supply for critical military installations, addressing strategic vulnerabilities associated with reliance on civilian power grids. The project will run for three years.

“Aim of the ARMIC project is to ensure a reliable electricity supply for at least 14 consecutive days, in line with military resilience standards,” a company spokesperson told pv magazine. “It also offers cost savings while meeting heating and cooling needs through integrated heat storage and cogeneration capabilities. Our goal is to achieve competitive energy storage costs and promote national technological sovereignty, applicable in both military and civilian contexts.” The project focuses on TRL 7–8 for battery technology, representing the stage immediately preceding full commercialization and operational deployment (TRL 9).

The ARMIC project includes the development of multiple pilot projects and brings together several companies and research centers. Key industrial partners are the Manchegan company GFM; Schunk, which provides graphite-based materials for battery manufacture; RBZ, an electronics systems assembler responsible for the TFV module of the batteries; and Esteyco, described by Silbat as a “reference engineering partner, collaborating with us since the company’s inception.”

Participating research organizations include the Institute of Solar Energy at the Polytechnic University of Madrid (IES-UPM), the Institute of Ceramics and Glass (ICV-CSIC), and the Control Robotics Laboratory (Robolabo-UPM), contributing to TFV module manufacturing processes.

The project is co-financed with approximately €3.4 million by CDTI Innovación, the state innovation agency under the Ministry of Science, Innovation and Universities, through the 2025 Science and Innovation Missions call. This initiative promotes research on cross-cutting and strategic challenges, strengthens the technological base of Spanish companies, stimulates public-private R&D&I collaboration, and reinforces Spain’s strategic autonomy in defense. Among more than 300 consortia that submitted proposals that year, the ARMIC Project received the highest evaluation score.

From pv magazine Spain