Auckland lawyer Andrew (name changed) had been keeping his Huawei P10 as a backup phone.
But with the Chinese phone maker losing full access to Google's Android software and app store amid US sanctions, the time had come to dispose of it.
Andrew wiped the phone. Then, as an extra precaution, he decided to smash it to pieces - in the same manner he had physically destroyed hard drives in the past to eliminate any possibility of forensic software being used to restore "deleted" data.
He grabbed a hammer, which he had on hand to hang artwork, then started to deliver a series of death-blows to the Huawei handset.
That's when things started to go south. After a couple of whacks, the phone's lithium-ion battery sparked alight.
"Flames started to shoot out of the sides like a Catherine wheel," Andrew says.
He resorted to smothering the phone with the only item on hand - an expensive blazer that was a gift.
The phone fire was extinguished, but not before there was so much smoke that Andrew feared it would set off his office's smoke alarms. He picked up a bendy sign and desperately waved to spread the particulate. He successfully avoided everything on the floor getting drenched, but was left with ruined blazer and scorch marks on the carpet around his desk.
A Japanese safety institute released a video that serves as a graphic reminder of the danger posed by damaged lithium-Ion batteries.
The batteries are extremely common in portable consumer electronics, providing power for smartphones, laptop computers, smartwatches and many other devices, and are typically safe. But if a battery is damaged, the results can quite literally be explosive.
As part of its work testing electronic components, the Japanese National Institute for Technology and Evaluation (NITE) tested batteries about the size of those used in cellphones. They were struck with a hammer then left on a workbench, unconnected from any apparatus.
Later - the period of time is unclear from the edited footage - one of the batteries ruptures with a bang, flying across the laboratory. A second clip shows a similar battery erupting in a shower of sparks.
The hammer blow to the battery caused deformations in the internal structure of the battery, which led to an internal short circuit. That created heat which sped up the reaction leading to more heat. It's a vicious circle called a "thermal runaway" that results in fire or explosion.
Thankfully, such explosions are rare. Some are due to manufacturing problems, like those that affected millions of Sony laptop batteries in 2008 or Samsung's 2017 Galaxy Note 7 recall, while others are due to damaged batteries. A 2013 incident where a Tesla Model S which packs hundreds of lithium-ion cells, catch fire was blamed on damage caused by road debris.
And in March, a fire investigator warned people to take care when charging products containing lithium-ion batteries following a fire which gutted one house and severely damaged another in Wanaka.
Fire and Emergency New Zealand fire risk management officer John Smalls said the cause of the fire was a lithium-ion battery exploding in a lean-to attached to the garage of the rear house.
Smalls said the battery would have exploded with quite a high intensity and it would have set fire to the plastics around it. He believed it could have been a power tool battery that was being charged.
Fenz has been sufficiently worried that it put out a report last year called "Lithium Batteries - What's the Problem".
Its introduction says, "Their low weight and high energy density have seen lithium-ion (LI) batteries being adopted in markets and devices that were previously not economic in terms of cost, weight or size. However, they have been shown to be susceptible to thermal run-away causing fires and explosions, resulting in significant injuries and loss of property around the world."
The report takes in issues from increasing incident numbers to proper charging techniques to the problem with counterfeits.
Speaking of which, the case of cheap replacement batteries sold online, it can be just down to shoddy design.
The advice from all battery manufacturers is the same. If your battery sustains any kind of damage, replace it.
Wait, it gets worse
Fenz report says lithium-ion battery incidents are on the rise, but also that statistics compiled by WorkSafe NZ unit Energy Safety NZ don't give the full picture.
It says, "There are some notable examples where data appears to be missing from the ESNZ data."
Those include an April 2015 fire that destroyed a home in Stoke, blamed on a lithium-ion battery left charging in the garage.
And it adds, "In February 2018, Fenz was called out to the Rocket Lab facility in south Auckland. Smoke was reported coming from two of the large batteries used in the Electron rocket. Although no one was hurt, this is a concerning incident given that each Electron rocket contains 1 megawatt of battery power."
The report expects lithium-ion battery-related incidents to increase over the next few years, in part because the number of gadgets powered by them is increasing as the likes of vaping devices, e-bikes and e-scooters take off.
Incidentally, thermal runaway is also a problem with electric vehicles.
A US National Transportation Safety Board details a half-dozen EV fires, including one where the car was stationary and battery fault caused the blaze. In another incident, fire offices had extinguished the blaze, but it reignited on a tow truck, thanks to "stranded energy" in the damaged batteries.
So does that mean you should give electric cars a swerve?
The NTSB says, "These fires illustrate what we all know. That severe crashes or component failures create safety risks in any car, be it gas, electric or hybrid."
All up, emergency services in the US attended some 170,000 car fires last year. But although EV fires were a component, they were an issue because fire crews often did not know how to avoid factors like battery re-ignition. A video (above) details one incident where a burning EV was doused in water from above, when in fact the battery compartment on the floor of the chassis needed to be cooled.
Lessons have been learned in Victoria, where a three-day blaze at a Tesla battery bank took 150 fire officers three days to put out. The blaze was extinguished late Monday, but fire crews are still taking temperature readings every two hours "as a precaution against reignition".
Fire and Emergency New Zealand's 2020 report puts the fiery EV issue in context, saying there have been 16 Tesla fires in the history of the vehicle and it quotes Elon Musk saying "Americans drive about 3 trillion miles per year according to the Department of Transportation. That equates to one vehicle fire for every 20 million miles driven, compared to 1 fire in over 100 million miles for Tesla".