Preventing Heat Propagation in Real-World Thermal Runaway Events
The Critical Role of Thermal Cell Barriers in Battery Pack Safety
Understanding Thermal Runaway:
The Reality of a 1,000°C Event
Thermal runaway is a high-consequence event where an internal fault can trigger a rapid spike in cell temperature. In first-hand testing, we’ve witnessed cells subjected to overcharging lead to temperatures climbing almost instantly to above 1,000°C.
Whilst thermal runaway is rare in deployed Electric Vehicle (EV) and BESS platforms, it remains a critical safety challenge for pack development. Whether triggered by mechanical damage, electrical fault, or manufacturing defects, the immediate priority is isolation.
Effectively managing the extreme thermal energy instantly, prevents it from propagating to adjacent cells, which is the difference between a single cell failure and the entire battery pack being compromised.
The Role of Thermal Cell Barriers
To delay and prevent cell-to-cell propagation, a thermal cell barrier has a deceptively simple job: withstand 900°C+ on the active face while keeping the reverse side within the standard temperature range, preventing the next cell from over-heating.
As passive safety precautions, they require no external trigger or reactive response; their value lies in providing immediate, predictable anti-thermal propagation performance.
Optimising Insulation Material Performance
The foundation of effective thermal cell barrier performance is based on its insulation materials. High-performance insulation materials deliver exceptional insulation performance with outstanding insulation to weight ratios.
Developing an optimal thermal runaway barrier typically involves engineering complementary material combinations tailored to the specific design, size, chemistry, and thermal management strategy of the battery pack.
Going Beyond Thermal Insulation to
Cell Compression
However, treating thermal runaway as a purely thermal problem overlooks that it’s also a mechanical one. Through our collaborations with major OEMs to achieve total propagation prevention, we’ve grown to appreciate that cell compression is a critical factor.
When a pouch or prismatic cell enters thermal runaway, it undergoes violent gas expansion. The swelling forces exert immense mechanical pressure inside the cell. This expansion force can completely crush thermal insulation materials.
Once a material is compressed past its design limit, its thermal insulation properties drop significantly. This is especially relevant for pouch cells, which lack a rigid outer casing to contain the swelling.
Updated GB38031-2025 Regulations: 2-Hour Containment Time
Starting on 1st July 2026, China officially enforces its updated EV battery safety standard, GB38031-2025. This introduces a strict "no fire, no explosion" requirement for 2 hours following a thermal runaway event, covering both new approvals and existing models sold in the region.
For any OEM exporting to or manufacturing in the region meeting a 2-hour delay or preventing thermal propagation completely can be achieved with advanced thermal cell barriers designed around your battery pack, that consider all factors required to effectively isolate thermal runaway.
Tecman ATP Pads:
OEM-Approved Performance
Engineered as advanced thermal cell barriers, Tecman’s Anti-Thermal Propagation (ATP) Pads provide the vital thermal delay and mitigation required during a runaway event. Our ATP Pads are already deployed by major OEMs across NMC, LFP, and hybrid chemistries.
Crucially, our ATP Pads can provide passive thermal insulation and are precisely calibrated to meet the exact cell expansion and compression requirements specified by cell manufacturers, without sacrificing performance under thermal load.
Fast Track Your Anti-Thermal Propagation Strategy
Tecman’s ATP Pads are fully commercialised and in serial production for global OEMs. By partnering with Tecman, engineering teams can:
- Accelerate time-to-market for safer, higher-performance battery packs
- Reduce R&D cycles
- Fully customise our ATP pad technology to your pack's unique architecture
- Achieve low-cost regional manufacturing with our high-efficiency, all-in-one manufacturing process
Contact our technical team today to see how our advanced thermal cell barrier technology can extend your battery cell life, optimise performance and improve battery pack safety.
We’re exhibiting at The Battery Show Europe 2026, Stuttgart
Free Sample Pack and Anti-Thermal Propagation Consultation
If you or a colleague are visiting The Battery Show Europe in Stuttgart this year then visit the Tecman booth, on the UK Pavilion (stand E30 in Hall 1), to speak face to face with our technical team. We will be showcasing advanced solutions at the forefront of battery thermal management and anti-thermal propagation technology.
Visit the Tecman booth to take full advantage of our exclusive show offers:
- Free consultation and 50% off a bespoke Thermal Cell Barrier specification and drawing for your project.
- Free Thermal Cell Barrier sample pack: Please note these are limited and must be pre-ordered before the show using this form.
View Our Battery Show Europe 2026 blog
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