Lithium-ion batteries are pretty safe. But sometimes, these batteries burst into flame. It’s no longer unknown that brands like Samsung have recalled 2.5 million Galaxy Note 7 due to allegations that the Li-ion batteries are catching fire. So, why do Li-ion batteries explode?
Lithium-ion batteries explode because of overheating. When cathode and anode come in contact, it causes overheating. As a result, the battery explodes.
However, overheating isn’t the only cause behind this incident. So what’s happening? Why do these batteries explode? What to do and how to prevent this phenomenon. Let’s find out.
How Lithium Batteries Work
Lithium-ion batteries work on the same principle as most batteries. These batteries use a chemical known as “lithium chloride,” evenly spread throughout openings in the anode and cathode.
In these batteries, lithium ions are free to move through a path created by two metal electrodes. Like in other batteries, chemical reactions occur when the electrodes are connected. The reactions release electricity from the battery.
What Happens During A Battery Explosion?
Lithium-ion batteries contain electrolytes in their positive electrode. Lithium ions pass through the separator and polymer layer to the negative electrode. The electrolyte produces hydrogen gas when it reacts with lithium at the negative electrode.
Hydrogen gas is highly combustible and can be ignited when exposed to an ignition source. During an internal short circuit, the separator can’t prevent electrons from reaching the positive electrode, where they react with lithium ions.
Lithium ions move to the negative electrode and create heat and hydrogen gas. The separator is damaged, the plastic case melts, and the pressure ignites the hydrogen gas.
Why Do Li-ion Batteries Explode?
Lithium-ion batteries are safe in normal conditions but can explode for many reasons. Here are some common reasons for exploding –
- Manufacturing Defects
Manufacturing defects are one of the reasons for exploding batteries. This is because of imperfections in the manufacturing process.
Sometimes small amounts of metallic particles remain inside, from where they can get into contact with electrolyte gel and ignite it. Also, there can be physical defects in the batteries, like a bulge at the end of the cell.
- Design Flaws
Designers not experienced in designing batteries might miss some crucial points that can cause an explosion.
For example, sometimes, the thickness of separators is less than the required one. This quickly makes contact between anode and cathode and causes overheating, which leads to an explosion.
- Abnormal Or Improper Usage
Improper usage of batteries like overcharging or using them in the wrong way causes explosions. Also, if a user throws the battery into fire or exposes it to extreme heat, it can lead to an explosion.
- Charger & Charging Issues
A bad charger can also lead to exploding batteries. This is because the charger is not supplying a sufficient current to charge the battery fully, causing overheating, which leads to an explosion. Poorly insulated or damaged batteries can also cause an explosion.
The charging temperature of a Li-ion battery is 5 to 45 °C; keep it in that range while charging.
- Low-Quality Components
Some batteries aren’t made of suitable materials and can explode. In such cases, the battery might be defective or low-quality. Low voltage batteries, designed for toy applications, often need a more powerful charger than those used for mobile phone or laptop batteries.
If a break in the electrical circuit between two cells in a battery, an arc can form and cause the battery to explode.
- Environmental Factors
Environmental factors like heat, cold or pressure can cause batteries to burst into flames.
In a cold condition, the top part of the battery expands more than its bottom part, which is in contact with electrolyte gel. When the internal pressure rises, it contacts the anode and cathode. This causes a short circuit and leads to overheating.
- Thermal Runaway
When the temperature inside a battery rises too high, it can cause the cells to rupture and release explosive gasses.
What To Do If A Lithium-Ion Battery Explodes?
Lithium-ion batteries are more energy-dense. High density makes them ideal for power tools and vapes. Due to their excellent energy density, lithium-ion battery explosions may be devastating.
If your battery has exploded, don’t try to disassemble it. Because the electrolyte is highly flammable, it can catch fire easily and burn you or your house. Never try to extinguish the Lithium-ion fire using water. Since lithium battery fire is a chemical fire, it will be more devastating if you through water on the fire. You should use Class C or Class D chemical fire extinguisher.
Don’t use a blowtorch to heat your battery; keep the fire away from you to prevent fires. Don’t try to put the remains of the exploded battery together again with other pieces of the batteries. Instead of throwing it away, you can call a service center.
How to Prevent a Lithium-Ion Battery from Exploding
You can avoid exploding batteries by taking a few precautions. Here are some things you should do to prevent a lithium-ion battery from exploding –
- Don’t charge the battery for a long time.
- Avoid keeping the battery lying on the bed or the bedside table, and don’t use a phone whose battery is overcharged or is short-circuited.
- Please don’t overload your Laptop or cellphone batteries by using them at least once every month.
- Keep the battery in a cool and dry place.
- Avoid direct sunlight, as heat can increase the risk of stress fractures that can lead to excessive heating and bursting.
- Don’t use a battery if it feels warm; check it using a thermal imaging camera to rule out any abnormalities.
- Avoid carrying batteries in your bags and storing them in your pockets. Also, while charging the batteries, ensure you stay away from children and pets.
Why Do Lithium Batteries Explode On Airplanes?
According to FAA, since January 23, 2006, there have been 373 aircraft accidents involving lithium batteries transported as cargo or luggage.
Lithium batteries can overheat during the flight due to increased cabin pressure. If a metal fragment punctures a partition of the battery, then lithium ions react with air and may catch fire.
- Will a lithium-ion battery explode in water?
No, Li-ion batteries do not explode in water. Chemicals that are put into the battery are not flammable in water.
- What temperature do lithium-ion batteries explode?
These batteries explode at 538 °C (1,000 °F). That temperature is called the auto-ignition temperature of Li-ion batteries.
- How common is it for lithium batteries to explode?
Lithium-ion batteries do not explode as often as people think. They explode on average once per million cell cycles.
We use Lithium-ion batteries in cell phones, laptops, electric cars, wireless headphones, fitness trackers, and e-cigarettes. They’re everywhere. Lithium-ion batteries are good and safe.
Then why do Li-ion batteries explode? It explodes because of overheating and improper usage.
So you must never oddly use a battery; always charge them according to the instructions and use them when fully charged. Protect yourself from accidental explosions by following our tips.