Safer Battery Storage: Thermal Management & Fire Protection Trends

Thermal runaway in lithium-ion (Li-ion) batteries has become one of the most pressing challenges for the global battery energy storage system (BESS) industry. As deployments scale from megawatt-hour to multi-gigawatt-hour capacities across residential, commercial and industrial (C&I), and utility sectors, the consequences of thermal incidents are growing more severe. Incidents range from fires, explosions, and toxic VOC release to significant financial and market disruption, as seen in South Korea's 2018 BESS crisis. In response, regulatory scrutiny is intensifying, and safety is becoming a central priority. Reflecting this shift, IDTechEx's latest report, "Thermal Management, Fire and Explosion Protection for BESS 2026-2036: Materials, Technologies and Players", forecasts the combined market for thermal management and fire protection systems and materials for battery storage to exceed US$25 billion by 2036, growing at a CAGR of 12.4% from 2025 to 2036.

 

This latest IDTechEx report provides a critical analysis of the BESS fire safety market, offering technical benchmarking of key materials and suppression systems, alongside reviews of both established and emerging players. It includes a detailed assessment of the evolving regulatory landscape and an evaluation of the technologies and strategies adopted by leading BESS developers, forming the basis for granular 10-year forecasts. The report also examines major material and system suppliers, benchmarking flame retardancy, thermal conductivity, and cooling efficiency against cost to highlight trade-offs and market opportunities.

 

 

The regulatory environment surrounding BESS safety remains fragmented, with countries and regions progressing at different speeds and adopting varying approaches. The US has moved toward a more comprehensive framework, particularly with standards developed under NFPA 855 and UL 9540. Meanwhile, the EU and China are evolving in distinct directions, often influenced by regulations developed for electric vehicles and adjacent industries.

 

This lack of harmonization presents challenges for global manufacturers, particularly when navigating cross-border deployments. At the same time, it also creates opportunities as new standards emerge, offering pathways for safety differentiation and compliance leadership. As BESS capacity expands and the public's expectations of safety increase, regulations will become an even more critical driver shaping technology choices and BESS market growth.

 

 

Thermal management (TM) and fire protection (FP) are expected to account for over 20% of total BESS costs by 2035. With battery cell prices declining, safety-related systems will increasingly dominate value allocation within BESS infrastructure. Active systems, including liquid cooling, advanced sensors, venting, and fire suppression, are forecast to capture most of this market, due to both their higher costs and central role in ensuring operational safety.

 

For developers and integrators, optimizing TM and FP systems offers one of the most effective pathways for reducing overall BESS costs while maintaining regulatory compliance. Innovation in both system design and material integration will therefore likely remain a central focus for the industry. In the current market, battery energy storage systems are adopting a combination of passive and active thermal management and fire safety technologies.

 

 

 

While materials represent a smaller portion of the market by value, they play a vital role in slowing or preventing the spread of thermal runaway. Traditional solutions such as mica and ceramics remain mainstays, providing cost-effective, durable, and proven flame-retardant properties. Their higher density, which can limit adoption in electric vehicles, is less problematic in stationary BESS installations, making them well-suited for this sector.

 

Beyond these, advanced materials are poised to expand their presence. Aerogels, which offer exceptional insulation performance at extremely low thickness and weight, are expected to see increased adoption as production scales and costs fall. Similarly, foams and thermally resistant coatings are being used to contain heat propagation across modules and racks. Intumescent coatings, which form a char when exposed to heat, are gaining traction, though challenges around post-event maintenance remain.

 

 

Cooling remains the foundation of effective thermal management in BESS, preventing hot spots, minimizing temperature gradients, and reducing the likelihood of thermal runaway. This latest IDTechEx report evaluates three key approaches:

 

Each method presents unique trade-offs in terms of cost, efficiency, and deployment suitability. With liquid cooling currently dominating, and likely to continue to, across both grid-scale and C&I BESS.

 

 

Along with cooling, detection and suppression systems are critical to minimizing the impact of thermal events. These range from condensed aerosol and sprinkler-based suppression to sophisticated gas sensors capable of detecting off-gassing in early stages of cell failure. Deflagration venting, which allows gases to be safely released, also plays a key role. Hybrid venting solutions, that combine passive and active features, are emerging to address the unique challenges of compact deployments and high-energy BESS units. Collectively, these technologies highlight the industry's move toward more layered safety strategies.

 

 

Thermal management and fire protection systems are central pillars of BESS system design, cost optimization, and risk management. IDTechEx finds that active systems such as cooling, sensing, and suppression will dominate expenditure, while passive systems such as materials like mica, ceramics, aerogels, coatings, and others, will continue to provide essential protection against the propagation of thermal runaway.

 

For more detail on technology performance, adoption trends for key thermal management solutions, and profiles of leading suppliers and developers, see IDTechEx's report "Thermal Management, Fire and Explosion Protection for BESS 2026-2036: Materials, Technologies and Players". The report also highlights how major players such as CATL, Tesla, and Fluence are each pursuing distinct approaches to thermal management and fire safety, creating a diverse landscape of opportunities for material and system providers.

 

For more information on this report, including downloadable sample pages, please visit www.IDTechEx.com/TMBESS, or for the full portfolio of research available from IDTechEx, see www.IDTechEx.com.