Solid-electrolyte batteries (SEBs) represent a next-generation energy storage technology that replaces the liquid electrolyte in conventional lithium-ion batteries with a solid-state material. This innovation promises higher energy density, improved safety (eliminating flammable liquid electrolytes), and longer cycle life. However, SEBs face significant challenges, including high manufacturing costs, limited scalability, and issues with interface stability between electrodes and solid electrolytes. Current developments are primarily at pilot and early commercialization stages, with automotive and stationary storage as key target markets. For DSOs, SEBs are not just an incremental improvement but a potential step-change, enabling new types of grid assets with fundamentally different safety and performance profiles.
Highlights
- The global solid-state battery market is projected to grow from approximately USD 1.5 billion in 2025 to over USD 8 billion by 2030, driven by EV and stationary storage demand.
- Europe is a key innovation hub, with initiatives under the EU Battery Alliance and Horizon Europe programs.
- Automotive OEMs and energy companies are investing heavily, but commercial deployment for grid-scale applications is expected post-2030.
- This strong investment pipeline signals a maturing supply chain and creates a clear technology roadmap for DSOs to monitor, with the potential for significant cost reductions beyond 2030.
Opportunities for DSOs
- Unlocking Urban Grid Flexibility & Storage: SEBs could enable high-capacity, safe storage systems for DSOs to manage renewable integration and peak shaving. Their key advantage is enabling the deployment of large-scale storage in dense urban substations or basements, where fire safety regulations and space constraints make traditional lithium-ion batteries difficult or impossible to permit.
- Managing the Impact of Ultra-Fast EV Charging: Faster charging and higher energy density in EVs will impact charging infrastructure planning and load forecasting. More importantly, stationary SEB systems can act as buffer storage at charging hubs. This allows DSOs to offer a lower-capacity grid connection, with the battery handling the extreme peaks of multiple ultra-fast chargers, thereby deferring costly upstream grid reinforcement.
- De-risking Grid-Scale Storage: Non-flammable electrolytes reduce fire risk in urban charging hubs and storage facilities. This fundamentally lowers the operational, public, and insurance risk profile of DSO-owned or operated storage, making it a more viable and socially acceptable grid asset.
- Enhanced Asset Longevity and Reliability: The promise of a longer cycle life means a lower levelised cost of storage (LCOS) over the asset’s lifetime. For DSOs, this improves the business case for using batteries as a long-term alternative to traditional “copper and steel” reinforcement.
Challenges for DSOs
- High Upfront Cost and Economic Viability: Despite long-term promise, the initial CAPEX for SEBs will be significantly higher than for mature lithium-ion technologies. DSOs must carefully assess the Total Cost of Ownership (TCO) to identify the specific use cases where the safety and density benefits outweigh the higher upfront cost.
- Power Electronics and Grid Integration: The performance of any battery system is dependent on its power conversion system (PCS). DSOs will need to understand the specific grid-forming and grid-following capabilities of the inverters paired with SEBs and how the complete system behaves under network fault conditions.
- Supply Chain and Manufacturing at Scale: While investment is high, the supply chain for solid-state electrolytes and components is still in its infancy. DSOs must be aware of the risk of relying on a limited number of suppliers for critical grid infrastructure in the medium term.
E.DSO Considerations
- Develop a Technology Roadmap: Monitor SEB developments for grid-scale storage pilots and EV charging strategies. DSOs should identify specific locations on their network where the unique safety and density features of SEBs would solve a problem that current technology cannot.
- Focus on the Business Case: Assess lifecycle costs and supply chain readiness before large-scale adoption. This analysis must quantify the value of enhanced safety, such as reduced land or infrastructure costs for fire suppression, to properly compare SEBs against incumbent technologies.
- Drive Standardisation Proactively: Address standardization and interoperability challenges early (CIRED Policy Briefs). DSOs must engage with manufacturers and standards bodies to ensure that future SEB systems are not proprietary “black boxes,” but are interoperable and controllable assets.
- Leverage Strategic Pilots: Engage in EU-funded pilots to evaluate real-world performance and safety. Pilots should be targeted to test SEBs in the most challenging and high-value environments, such as densely populated city centres or critical infrastructure sites.
Potential Use Cases
- Urban Substation Deferral: Deploy compact, fire-safe SEB storage inside inner-city substations to manage peak load and defer the need for extremely disruptive and expensive transformer and cable upgrades.
- EV Charging Hub Grid Buffers: Use SEBs in buffer storage systems to enable ultra-fast charging services with a minimal grid connection footprint, absorbing peak demand locally.
- High-Resilience Microgrids: Install SEB systems in critical infrastructure like hospitals or airports, where their enhanced safety and reliability can provide long-duration backup power and black-start capability.
- Enabling Firm Flexibility Services: Offer SEB-based storage to industrial customers. Their enhanced reliability and predictable performance make them a superior asset for providing guaranteed, dispatchable flexibility services back to the DSO.
Ongoing Projects
- SOLVE (2024–2028): Develops Generation-4b solid-state batteries with lithium-metal for sustainable mobility. Aims for circular production and high energy density for electric vehicles.
- SOLiD (2023–2027): Pilot manufacturing of solid-state batteries using sustainable materials and recycling concepts. Emphasis on industrial scale-up and digital quality assurance.
- HELENA (2023–2026): Develops halide-based solid-state batteries for electric vehicles and aerospace. Targets high current capability and fast charging for demanding applications.
- HyLiST (2025–2029): Launching in 2025 to create hybrid lithium-metal solid-state batteries. Focus on scalability, industrialization, and strengthening the European value chain.
Last update: 8 December 2025