Hoverboards: EXPLODE? CATCH FIRE?

[TheBlackAdder]

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Whaaa?

More than 15,000 "hoverboards" have been confiscated at U.K. ports and airports in recent months, after being regarded as "unsafe" for personal use.

Officers from the U.K.'s Trading Standards have inspected over 17,000 self-balancing scooters since October 15 and seized 88 percent of these self-balancing scooters, over fears they could explode or catch fire.

The self-balancing scooter has fast become the "must have" gift for Christmas 2015, with the port and borders teams revealing they'd seen a "significant spike" in the number of these vehicles in recent weeks, as the holidays approach.

However, concerns have been raised over safety issues with the product's design including concerns over plugs, batteries, chargers and cabling. Many of the items apprehended and tested were found to have plugs without fuses, which the watchdog said increases the danger of hoverboards from overheating, catching fire or even exploding.

http://www.msn.com/en-us/money/technologyinvesting/more-than-15000-hoverboards-seized-over-safety-concerns/ar-AAfYJB3?li=BBnbfcL&ocid=mailsignout


UPDATE: The gist is to BUY GENUINE only. Years back, BoingBoing did a piece on how most of the batteries sold in the US are fakes, fallible designs without safety mechanisms in them, labeled so well, their vendors could not tell apart from OEM. That's why, when you see laptop batteries on eBay or other sites, be leery about them because there is no way to tell if they are true factory parts or knock-offs.


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[leftofcool]

1. Well shit! There goes my Christmas!

Meh! Hover boards are like skinny jeans. Not for grandmas!

[TheBlackAdder]

2. Soon, I'm getting a rancher. I don't know how many more falls down the split-level stairs I can do!

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Let alone risking on a hoverboard. I used to skateboard back in the 60's and 70's, I got on one at a toy store and wiped out on the hard floor. I laid there for a little while and my bones hurt for weeks!


Update:

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[jeff47]

3. Sorta

It looks like there's a bit of intermixing of two things here.

First, the minor one: In the UK, most plugs have their own fuse in them. This is because of how many of their houses are wired. A lot of their houses have fewer circuits that can carry more amperage, because it requires pulling less wire through old houses. That means you need a fuse in the plug so that the plug can stop too much current from going down the wire.

In the US, we have a lot more circuits, and just require the plug and device to be able to handle the current those "smaller" circuits carry, allowing us to rely on the circuit breaker in the electrical panel to prevent fires.

The bigger issue is lithium batteries are inherently unstable. If they are not kept within a relatively narrow range of voltage, they catch fire and explode. The batteries are monitored by some electronics in the battery to keep the battery within that range.

Battery manufacturers can do some to help avoid this by using more expensive chemicals within the battery. But when you're talking about cheap knock-offs, they're going to use cheap battery chemistry, monitored by cheap electronics.

(Btw, always buy replacement lithium batteries from the original manufacturer. The cheaper ones you find might be fine...or they might be built cheaply. OEM batteries are the only way to know you're not getting cheap batteries)

[TheBlackAdder]

4. On YouTube, there are US videos of homes burning down, hoverboards burning. nt

[jeff47]

5. That would be the "cheap batteries" part.

Same reason you can find videos of cell phones and laptops burning.

[TheBlackAdder]

6. Yes, and they were addressed by circuitry.

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In the old days, batteries used to have "memory' that is why it was best to deplete them and fully charge them to prevent an accelerated loss of power and possibly the reversal of a cell's polarity.


When the laptops were catching fire, they found that Li batteries were only good for around 1200+ charges before they could fail (update - normally it's between 1,600 and 2,000 charge cycles). There can be circuitry that checks the voltage ranges, but most just have a counter on them to count how many times the battery was charged, as each time it charges the cells degrade. The idea is to disable the battery before an internal short occurs. When that counter hits, it no-ops the battery. (update: they don't have good ways to tell the battery is about to short, so they make a safe guess, at around 1,000 or more charges. They use the charge cycle as an average, just like with printer click charges, to build an estimate of this possibility. Whether you charge it for 5 mins or 1.5 hours, that charge cycle goes against the anticipated battery life.)

Having worked in IT for 30+ years, it is common practice to minimize the charge cycles. I've had family and friends who would go through a laptop battery in less than a year, while we run ours for 3-4 years or more before replacing. They would take their laptop or cordless phone from room to room and plug it in, during the course of a day, they might plug it in a dozen or more times, each time constituting a click charge-in print terminology (don't get me started on how printers are designed to rip off residential customers).

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[jeff47]

7. That's how older lithium batteries worked.

Now the electronics monitor the individual cells directly. That's why chips like this don't include a counter.

These batteries still take their heaviest wear going from 95% to 100% or from 30% to 0%. So constantly re-plugging can cause you to go through that 95-100 a lot more often.

[TheBlackAdder]

8. They're $10 a piece so they aren't in equipment under $100-$200 dollars, inc. residential UPS. nt

[jeff47]

9. Yeah...it's an example not an exhaustive list.

That particular chip is designed for EVs and other heavy loads.

[AngryAmish]

10. Sounds like OP is Jeremy Clarkson.

[GeorgeGist]

11. FAIL TO HOVER!