Hoverboards Overloading their batteries?

[Dauntless]

So the airlines are starting to forbid them on planes. The culprit is fire issues from those firebomb lithiums. There's the beginnings of discussions that they are overloaded in normal use on a hoverboard. Well, it does make since trying to keep the batteries to a minimum, with much said about the batteries that can't handle their full rating.

Time for the experts here to solve the problem.

http://www.wired.com/2015/12/why-hoverboards-keep-exploding/

 

[dogman dan]

Pushing the c rate is a good way to drive a battery out of balance, which can lead to an overcharge if the bms is primitive enough.

My suspicion is the problem is more just the same old one, cheap construction, a bit of movement of the battery in the container, then you chafe through something getting the usual cause of battery fires, a short circuit.

 

[KarlJ]

must be crap cells to catch fire doing 6mph....
how much power can it possibly use!

 

[dogman dan]

I'm still betting on crap assembly.

 

[nicobie]

Looks like Amazon banned all of them. It appears that the bigger problem is folks ending up in the emergency room after falling off the things.

 

[999zip999]

Hoverboards go the way of lawn darts ?

 

[danielrlee]

Looks like Amazon banned all of them. It appears that the bigger problem is folks ending up in the emergency room after falling off the things.

Nonsense! If that were the reason, none of us would be allowed to ride bikes.

 

[aroundqube]

http://www.usatoday.com/story/tech/personal/2015/12/14/amazon-stops-selling-some-hoverboards-over-safety/77275814/

 

[mistercrash]

Good companies building good hoverboards are loosing business because the crappy Chinese knock offs catch fire. So what else is new.

 

[Dauntless]

Bicycles get the grandfather clause from back when it was legal to be an adult and take responsibility for yourself. No such luck for the hoverboard.

 

[Chalo]

Bicycles get the grandfather clause from back when it was legal to be an adult and take responsibility for yourself. No such luck for the hoverboard.

I think the hoverboards' problems are mostly attributable to them being crap.

Through a combination of sound engineering and the legislative process, Segways are not only safe, but legal just about everywhere. These hoverboard things are not Segways.

 

[ejonesss]

more than just overloading the batteries it is possible that they are omitting the bms thereby over charging some cells due to them being out of balance.

if i was to get one i would replace the battery with one from hobbyking and get a bms or battery alarm for low battery and use hobby charger for charging since they have proper balancing.

 

[Hillhater]

Through a combination of sound engineering and the legislative process, Segways are not only safe, but legal just about everywhere. These hoverboard things are not Segways.

Hmm?, maybe for your area, but too much of a generalisation.
There are large parts of the western world where Segways are illegal in public areas.

A lot of speculation about these hover boards, cheap batteries, BMS, Chargers, bad wiring, etc....
Somebody on here must have one they can dismantle and see if there is anything obvious .
Personally , I am with Dogman, from the videos I have seen, the battery location and physical protection leaves much to be desired.....even with reputable Samsung batteries they have been known to flame !

EDIT.
More digging shows that at least some of these packs (9s 2p ?) have a circuit board inside the shrink wrap..a bit like the laptop packs...presumably to manage cell balance etc.
Don't see what other protections it may provide though, for overload /over voltage/ LVC , etc.
So maybe the problem is not with the packs themselves but other build factors or components.

 

[999zip999]

The fire boards or hoover boards where were they purchased ? For how much ?
They need to be certified just because of these. We need government ? Look at the gas leak Porter Ranch California

 

[dogman dan]

You want to make any battery get really hot, short it. I've very little doubt the real problem with the flaming hoverboards begins with a shorted battery.

A cheaply assembled battery will not have the extra paper insulation between the can and the nickel strips on the positive side of the cells. Then if one cell has a short bit of shrink, the positive nickel strip eventually touches the negative can. Even the very best quality cells get hot as hell if they are allowed to short. Other places can short as well, but I'm betting it's the assembly of the battery itself.

 

[Dauntless]

That was supposed to read:

Through a combination of sound engineering and the legislative process, Segways are not only safe, but legal just about everywhere. These hoverboard things are not Segways.

Hmm?, maybe for your area, but too much of a generalisation.
There are large parts of the western world where Segways are illegal in public areas.

[youtube]ACGeWm8dcu8[/youtube]

 

[nutnspecial]

Nice one with mike, good timing since there's that show coming soon.

I have seen a hoverboard used improperly, used by a naked chick doing porn,
It overloaded my mind, and yes I actually am serious :lol:

 

[Hillhater]

Another house fire last night (in Melbourne) attributed to a "hover board" exploding 10 mins after being plugged in.
A lot of miss information now being spoken about non balancing chargers, etc by quasi battery experts
In reality, these are no different to laptop packs with internal control circuits ( same cell type, similar configure, etc), and a simple external charger.
To me it seems the problem is just quality of components, design and construction.
If a product doesn't have the correct standards testing certification and associated markings, then it's probably a high risk product to be avoided !.
If we learn nothing else, this reconfirms the misconception that 18650 cells are "safe".

 

[mxer]

I have one of these which I think the battery is faulty?...

Board just cuts out no warning? Takes a minute or two for it to switch on again..

Next time it happened I checked the motherboards main voltage in from battery and it shows very low voltage (lowest I've seen is 8v) gotta be quick to open up when it cuts out, then the voltage climbs upto 35v and the unit switches back on...

if I unplug the battery to check voltage when it cuts out, straight away it shows 35v?, is the bms resetting as soon as I unplug it? Or is the motherboard faulty?..

It's a difficult one to solve?..help!

I'm betting towards a faulty cell, shutting of the bms?...but it's a guess?

Anyone else experiencing this?....

Many thanks in advance...

 

[parabellum]

I have one of these which I think the battery is faulty?...

Board just cuts out no warning? Takes a minute or two for it to switch on again..

Next time it happened I checked the motherboards main voltage in from battery and it shows very low voltage (lowest I've seen is 8v) gotta be quick to open up when it cuts out, then the voltage climbs upto 35v and the unit switches back on...

if I unplug the battery to check voltage when it cuts out, straight away it shows 35v?, is the bms resetting as soon as I unplug it? Or is the motherboard faulty?..

It's a difficult one to solve?..help!

I'm betting towards a faulty cell, shutting of the bms?...but it's a guess?

Anyone else experiencing this?....

Many thanks in advance...

Can you use the board after it switches ON or it switches Off right again under load? If you have access to cell groups, check the voltage of every series after shut down. Inspect integrity of "balancing " wires, connections and solder joins from every cell group till BMS. Report back your findings and we all love pictures.

 

[mxer]

Thanks for the input..

Yes board is fine fresh off the charger for a good while, the board is supposed to let you know when it's getting low ie, green flashing battery red flashing etc, but it doesn't just shuts off with no warning (solid green light) so you can imagine it's quite dangerous...so we limit ourselves to about 20 minutes or so and not load it too much.

Did originally think the motherboard was faulty, but after voltage checks to the board it's making me think it's the battery shutting down to early? Unless the motherboard bms is faulty but unsure if it manages voltages?

Thanks again for the input..really appreciate it.

 

[parabellum]

This behavior appears to be the result of low cell group. My primery suspicion is, battery level SOC is measured by the main board but cell level protection is made by discrete BMS board. It also looks like logical shortcut in cheap production, just take available COTS and connect in to system.
As result, main board may not know the moment where particular (damaged: can be low capacity or higher R) series reaches LVC and is shot down by BMS it just expects healthy pack. Do you have warranty on this board?

 

[mxer]

No warranty, as it was second hand?

I do have another none faulty hoverboard, so I'm thinking when that warns me it's low, transfer it over to see if that does the same to eliminate the motherboard?. Or vise versa?.

I'll report back my findings, with photos

Thank you for your quality input..great stuff.