One cannot talk about exploding batteries without referring to the ill-fated Samsung Galaxy Note 7. As much as we hate seeing a smartphone like the Galaxy Note 7, arguably one of the best smartphones Samsung has ever produced with loads of power and quite a few unique features, we have to accept the battery issues and move forward.
However, Note 7 is not the only smartphone to have gone through such issues. It happened with Nokia in 2007, and we are pretty much sure it may occur in the future again because smartphone vendors are extensively focusing on delivering slimmer devices by compromising on design aspects, which is the case with the Galaxy Note 7.
But is this the only factor or are there any other factors that lead to the explosion of batteries in smartphones? Let's find out.
Before we do that, let's get to know how the batteries in smartphones work in the first place.
Note: Given the fact that most smartphones use Li-ion batteries, we will mostly focus on explaining how Li-ion batteries work.
Li-ion battery and its working
As with the case of most batteries, the Li-ion batteries consists of three parts - the cathode, the anode, and the electrolyte.
The anode (holds negatively charged ions) and cathode (holds positively charged ions) are nothing but electrical terminals located on either side of the battery. These are called electrodes, and the chemical between these electrodes is called electrolyte, which helps conduct electricity. Both the cathode and anode are in the electrolyte but are separated by a physical barrier to restrict them from touching each other.
The cathode pushes positive charge through the electrolyte towards anode which after attracting it, sends power to different components of the phone, which means discharging in other words. And the exact reverse of this process is nothing but charging - something which happens when you plug in the charger.
So, why do they explode
Well, after all, they are batteries and batteries degrade over time. That's precisely the reason why a two-year-old smartphone doesn't deliver the same battery life as a six-month-old smartphone does. Moreover, these batteries are highly temperature sensitive (have very low melting points - around 180-degree Celsius) and can explode mainly for two reasons: heat and physical damage.
Like mentioned earlier, the electrodes are separated by an electrolyte (usually a paste like substance) which is highly volatile. When this paste (full of superheated liquids filled with melted metals) ruptures out of a battery casing due to physical damage, it creates an explosion.
Is there any way to stop smartphone batteries from exploding, you ask?