Why Lithium Batteries Catch Fire (And What You Can Do About It)

If you own a smartphone, laptop, or electric vehicle, chances are you rely on lithium-ion batteries every day. But did you know these batteries can unexpectedly catch fire and cause injury or property damage?

It’s a disturbing fact, but why lithium batteries catch fire is an important question for consumers. In this guide, as a professional lithium battery packs supplier, I’ll explain the science behind lithium battery fires, look at some recent examples, and share tips to prevent fire risks.

Why Lithium Batteries Catch Fire?

Lithium-ion batteries are everywhere these days for good reason – they pack a lot of power into a small, lightweight package. However, certain flaws make them prone to overheating and fire under the right conditions.

Here are the main culprits behind lithium battery fires:

Thermal Runaway

The biggest danger is something called “thermal runaway.” This is a chain reaction where heat causes chemicals inside the battery to destabilize.

As temperatures continues rising inside the battery, pressure builds up. Eventually the battery’s casing ruptures, exposing the flammable electrolyte liquid to oxygen.

When the electrolyte ignites, the resulting fire is intense and difficult to extinguish. Fires can reach 1,000+ degrees Celsius in seconds!

Thermal runaway is more likely to happen when batteries are overcharged, punctured/damaged, or exposed to excessive heat.

Internal Short Circuits

Lithium metal plating during charging can lead to hair-like structures forming inside the battery. Over time, these metallic dendrites penetrate the separator and create an internal short circuit between electrodes.

The large current flow from a short circuit generates intense heat. Thermal runaway and fire can occur if temperatures spiral out of control.

Manufacturing Defects

Sometimes contaminants make their way inside lithium batteries during production. These metal particles floating around can cause short circuits and fire risks.

Thin or defective separators are another factory flaw that allows dendrites to penetrate more easily. Rigorous quality control is necessary to prevent unstable batteries from leaving the assembly line.

External Factors

External factors, like physical damage, can directly trigger battery failures.

For example:

1. Exposing the battery to high ambient temperatures
2. Penetrating or crushing the battery enclosure
3. Attempting DIY disassembly/repair

All these actions can damage the battery internally and cause catastrophic overheating.

Issues With Charging

Using faulty or incompatible chargers is another common cause of lithium battery fires.

Problems include:

1. Poor insulation causing sparking/heating near battery
2. Unofficial chargers overcharging/damaging battery over time
3. Modern li-ion batteries have overcharge protection baked in. But it’s still unsafe to use unapproved chargers.
4. Stick to OEM adapters.

Low-Quality Components

With falling EV battery prices, some manufacturers cut corners on critical components:

1. Battery Management Systems (BMS)
2. Internal wiring
3. Cooling systems

This seriously impacts safety and makes failure during normal use more likely.

Recent Lithium Battery Fires in the News

We’ve all heard reports about phones, laptops, or electric vehicles bursting into flames recently. Why does this seem to be happening more often?

For one, demand for lithium batteries is skyrocketing globally. More devices than ever rely on lithium technology, upping the odds of fire incidents.

Population density is another factor, especially in cities where electric bikes and scooters are popular. The infrastructure often isn’t equipped to handle charging millions of devices simultaneously.

Let’s look at some notable recent lithium battery fires:

New York City E-Bikes

Hundreds of fires in New York City have been connected to e-bike and e-scooter batteries in the past few years. These incidents resulted tragically in over a dozen deaths so far.

The city has over 10,000 delivery cyclists relying on lithium batteries daily. Improper charging practices in crowded apartment buildings with inadequate electrical systems have mainly fueled this crisis.

Tesla Vehicle Fires

Electric vehicles clearly supply the most power-hungry lithium batteries consumers own. It’s no surprise these high-capacity batteries occasionally fail, although Tesla maintains fire risks are still lower compared to gas cars.

In a few disturbing cases, Teslas have combusted into flames spontaneously while parked and turned off. Thermal runaway from factory flaws or minor collisions likely caused the fires.

Energy Storage Systems

Large-scale batteries provide backup electricity for buildings and the grid, but they’ve also been behind some massive fires. One notable example saw a 2 megawatt battery explode at an Arizona Public Service facility in 2019, injuring several firefighters in the process.

These examples underscore why enhanced regulations and fire prevention standards are needed for lithium battery technology.

4 Tips to Prevent Lithium Battery Fires

Luckily there are a few key steps consumers and manufacturers can take to minimize fire risks from lithium batteries:

1. Avoid Knockoff Chargers & Accessories

Many fires start from using substandard or incompatible chargers. Always use the charging cord that came with the device, or an authentic replacement recommended by the manufacturer.

2. Don’t Overcharge

While lithium batteries have protection against overcharging built-in, it’s still best not to leave devices plugged in all night after the charge cycle completes. Overcharging strains batteries over time.

3. Handle With Care

Dropping your phone or laptop can damage lithium batteries in ways that aren’t visible. Any dents, odd smells or hissing, or signs of leaking are red flags. Safely dispose batteries exhibiting these warning signs.

4. Store Properly

Don’t leave lithium-powered devices in direct sunlight or other hot locations for extended periods. High ambient temperatures accelerate the chemical reactions inside batteries, increasing fire risks.

With global demand doubling in the next few years, the lithium battery industry clearly has work to do improving standards. But a bit of consumer awareness regarding best practices goes a long way too.

Understanding why lithium battery catches fire is the first step towards safety. With increased diligence from manufacturers and users alike, we can feel confident our devices won’t literally blow up on us!