Over the past year, Nvidia's Shield Tablet has become one of the top tablets for Android users. Today, the company recalled a subset of the devices, saying they're prone to, uh, no easy way to say this, exploding into flames.
There's a very easy way to check if your Shield is involved in the recall, and Nvidia will send you a replacement with a better battery. The problem affects all of the tablets sold between July 2014 and July 2015 — Nvidia is understandably mum on what's causing the problem, saying simply that the batteries are overheating and causing fire hazards. But the company is also careful to note that anyone who bought a tablet within the last year should stop using it now, so the malfunction sounds fairly serious.
It's a sad recall, because the Shield has been a fairly popular and well-received option for people who want to play games on their tablets. Gizmodo's own Eric Limer said "it should probably be your next Android tablet no matter how much button-mashing you do." Still, the review noted that the tablet's battery drained surprisingly quickly — and a cursory Twitter search shows that consumers had plenty of problems with battery drain and heat:
I've been really excited to try the Shield Tablet but every time I pick it up the battery is dead. I've had it 6 months.
— David Ruddock (@RDR0b11) March 23, 2015
@nvidia whilst I am playing half life on my Shield Tablet I have noticed it gets rather hot, so how does the tablet not overheat?
— GameFreak01048 (@GameFreak01048) December 29, 2014
I've recorded new games with my new tablet controller and the tablet gets way too hot (shield tablet) guess over clocking is out the window
— nikbailey( ͡° ͜ʖ ͡°) (@NikOwnzYu) April 29, 2015
So we know that heat was an ongoing issue, though it's unclear if any fires actually occurred.
Why Can't Lithium Ion Batteries Stop Exploding?
The Shield has a lithium ion battery, which means that its battery was susceptible to a hazard known as thermal runway.
Inside a normal lithium ion there are several cells — each containing an anode and cathode, with a liquid electrolyte between them. Ions move from the cathode to the anode, and in reverse when it discharges. When this process happens too quickly, the cells get hot — and sometimes, melt the very important insulators that contain the parts. Then temperatures begin to rise — and the cells next door get hot, too. Soon they're short circuiting. And so on — hence thermal runaway.
As we noted in our review, the Shield's battery life was pretty pitiable. And remember, this was a tablet that was supposed to support battery-intensive gameplay and video use. Which means that users were likely discharging and recharging their devices very quickly and very often in frustration. It's no surprise the batteries couldn't take it. This is a problem that affects a huge portion of lithium batteries, from the compact batteries in tiny smartphones to the massive units that power the electrical systems in the Boeing Dreamliner.
So in the end, this is a great example of a manufacturer mismatching the battery inside a new device to the way users are supposed to use it.