Thermal bridges and batteries : Why choosing the right materials can save lives


Pont Thermique: A hidden danger in assembly
Don’t be fooled by appearance. A lithium battery may look safe because it’s new, but its internal design sometimes conceals major risks. One of the most common causes of fire is the choice of insulation materials.
In many assemblies, poor-quality connectors are used or, even worse, polyurethane (PU) foam is used to absorb shocks. To the non-expert, this foam looks a lot like silicone foam. However, PU foam is a cheap, flammable wick, while non-flammable silicone, although three times more expensive, is the only effective barrier.
“If the material between the cells is flammable, it becomes the vector that spreads thermal runaway to the whole pack.”

Common market abuses
We regularly observe practices that favour margin over safety:
- The use of conventional PU foams: they ignite instantly, releasing toxic gases.
- Poor gaskets: under the effect of heat, they melt and leak, causing short-circuits between the various internal equipment.
- Lack of certification: Using components without a fire-resistance standard is taking an ill-considered risk. A cursory test is no substitute for full, rigorous certification.

Our ethics: The standard for non-flammable silicone
We have chosen to make no concessions when it comes to safety. Our added value is based on the systematic use of top-of-the-range materials:
- Extreme-temperature resistance: Silicone remains stable and integrated where lower-end foams disintegrate.
- Self-extinguishing properties: When exposed to flame, our materials do not propagate fire.
- Certified cell supports: We banish homemade joints in favor of rigid, non-flammable cell supports.
- Test traceability: Our metrology equipment generates precise test reports, confirming the conformity and safety of each assembly.
Conclusion: Sustainability for safety
Unlike low-grade materials that degrade with time and equipment vibrations, our standards ensure maximum longevity for your lithium batteries, while guaranteeing absolute safety for users.
Reality in the field: The PL ONE Manifesto
Every day, the Pro Lithium team fights on three fronts to transform market standards:
- Education in the face of technical ignorance.
- Warning against user overconfidence.
- Justify the value of safety in the face of penny-pinching.
We don’t sell components, we sell serenity
This is what makes the PL ONE approach so indispensable. Buying a 10 kW pack assembled with disparate cells means accepting to live with a time bomb under your feet.
Our customers make a radically different choice. They know that every piece of equipment has been designed with one thing in mind: infallibility. We don’t sell products, we sign an insurance contract with you.
The weak link theory
“A battery is like a chain: its overall strength is equal to that of its weakest link.”
Inserting a used cell in the middle of a new pack is like fitting a smooth tire to a Ferrari. In a straight line, the illusion is perfect. But at the first sharp bend – or the first quick charge – everything falls apart.
Compensating for the unpredictable
As experts, “we didn’t know” is an admission of failure that we refuse to accept. We can never predict when a cell might leak, but we can decide what will happen next. That’s why flame-retardant silicone is our standard: so that the unpredictable never becomes a tragedy.
