Why can lithium-ion
batteries catch fire? Causes and solutions

Introduction

Lithium-ion batteries are everywhere: in our smartphones, our electric bikes, our portable tools, and of course, our electric vehicles. While they’re prized for their power and compactness, they also pose a real fire risk, which can be difficult to predict.

In this article, we analyze the scientific causes of these fires and the concrete solutions to avoid them, both in professional and domestic use.

Causes of lithium-ion battery fires

Thermal runaway: a chain phenomenon ⚠️

The main risk is thermal runaway, an uncontrollable reaction caused by overheating. When the temperature exceeds a certain threshold (up to 400°C in a few seconds), a cell can release all its energy and cause an explosion or fire.

Common triggers :

🔹 Shock or physical damage : An internal puncture creates a short circuit.

🔹 Electrical overload : excessive or poorly controlled charging generates metallic deposits (dendrites) which pierce the separator.

🔹 Room temperature too high : exposure to the sun, poor ventilation or proximity to a heat source.

Internal structural failures

The high energy density (250 to 700 Wh/L) makes lithium batteries very sensitive. Organic electrolytes, which are naturally flammable, easily ignite in the presence of oxygen if the cell is compromised.

Deferred risks after impact

An often-overlooked danger: a fire can occur several hours after an impact. Internal damage develops invisibly, and a seemingly stable battery can ignite up to 72 hours later.

How to prevent lithium-ion battery fires ?

🔧 Good usage practices

🔹 Use certified chargers with automatic cut-off systems.

🔹 Avoid excessive rapid charging, which degrades the internal chemistry of cells.

🔹 Inspect your batteries regularly : swelling, odor, and overheating are warning signs.

📦 Secure storage

🔹 Store batteries in a temperate environment (15°C to 25°C).

🔹 Use fireproof containers for transport and storage: 👉 Discover our secure storage solutions for batteries

🔹 Keep away from any flammable products while charging.

🚨 React in the event of an incident

🔹 Flood massively with at least 3000 L of water to cool and stop thermal runaway.

🔹 Immediately isolate the damaged device in a ventilated and safe area.

🔹 Use fire blankets specific to lithium batteries : 👉 Our covers comply with DIN SPEC 91489 standard

Alternative solutions in development

Manufacturers are working on safer batteries, including those based on :

• solid electrolytes (non-flammable),
• ceramic separators (more heat resistant).

But these innovations, although encouraging, remain costly and inaccessible on a large scale today.

What to remember 🔍

➡️ Lithium-ion batteries offer high energy efficiency, but their chemical design makes them susceptible to mishandling.
➡️ 78% of battery fires could be prevented by following simple charging, storage, and visual inspection guidelines.