Fisker Karma's catch fire underwater

[Captain Awesome]

Originally Posted by Scalded Dog

Of course... my point precisely, in response to the claim of 300 volts found in the FizzCar... massive voltage CAN be a moot point.

I didn't understand that you were not aware that the 300V is the main circuit that drives the electric motors. It's not a little spark. It's the whole enchelada.

[ModBargains.com]

Wow that's insane... Sucks for those guys.

[upflying]

Originally Posted by Scalded Dog

A regular ol' car or truck has something north of 20,000 volts running through it. Ask anybody who has ever pulled the plug wire off of a running lawn mower, or tried pulling the wires off of a '76 Cutlass at idle and has gotten permant nerve damage done to his hand... those folks will be happy to testify that there's a lot more than a 12 volt trickle running through them dang things!

Don't forget the 50,000 volt Tasers cops use. It hurts but doesn't kill you. As noted, Tasers have no amps.
Electric chairs use about 2000 volts at 8 amps.

[Number 3]

Originally Posted by Scalded Dog

A regular ol' car or truck has something north of 20,000 volts running through it. Ask anybody who has ever pulled the plug wire off of a running lawn mower, or tried pulling the wires off of a '76 Cutlass at idle and has gotten permant nerve damage done to his hand... those folks will be happy to testify that there's a lot more than a 12 volt trickle running through them dang things!

Also you are talking about ignition voltage on a running car. Sitting in a puddle of water it's still 12 V.

Yes, I've had the experience of lying on my back on the other side of the garage checking the old points on a pre 75 ignition system. :(

[DGthe3]

Originally Posted by Captain Awesome

A 12V lead acid battery in the typical normal car only has a few amps of current. The LiIon battery in a hybrid battery can supply hundreds of amps. The Fisker battery nominally has 336V and amps in the hundreds if not more.

Voltage is like electrical pressure. A large volatage is like a higher pressure. Amperage is like the size of a pipe.

So, if you have a 1/4" pipe with 12PSI in it, you could easily stop it by sticking your finger over the end of the pipe.

The same 1/4" pipe with 336PSI in it you could probably stop with your finger as well, but it would be painful.

Increase the size of the pipe to 1" diameter (more amps) and at 336PSI it would probably take your arm off.

People think these batteries are so wonderful, but they demand a lot of respect. They contain all of the potential energy needed to move a vehicle for the rated distance in a form that is very much ready to be released in an instant.

The battery wants to get rid of all that stored energy and it takes only a small problem to unleash it.

A whole tank of gasoline contains all the stored energy to drive 300-500 miles (depending on the car) and you can unleash it with a fire, but it is released in a relatively slow manner because it needs to combine with oxygen to burn and this reaction is limited by the surface area of the gas.

You would have to convert all of a tank of gas into a vapor and mix it with oxygen and contain the vapor mixture somehow and ignite it to achieve the same effect as shorting out a massive battery.

The battery discharge is really only limited by the internal resistance and so it wouldn't be able to fully discharge instantly, but a dead short would release a huge amount of it all at once. A lot more than a 12V car battery or some dino juice that leaked out.

I know all about voltage and amperage and how batteries work. Amperage is a function of the voltage supplied and the resistance of the circuit, not a driving element of the circuit. The maximum amount a battery can supply has little to do with how much it actually supplies in a given circumstance. If the circuit needs 5 amps, the battery supplies 5 amps -not 60 amps (or whatever) it could supply. It will only do that if the circuit is needs 60 amps.

Now, back to the burnt down Karmas. While its true that the battery is in the 300V range, not every single component of the electrical system operates at that voltage level. In fact, about the only thing that does is the drive motors. Most of the remainder is at the same voltage as any other car. Afterall, it is an awful lot easier to bring down 300V to 12V (or 60 or 3.87 or 189) and use a standard component (like a power window motor) at a normal voltage than it is to redesign all those other components to run off of 300V. Consequently, the vast majority of the wiring on hybrids and EVs is no more dangerous than it is in a conventional car (and keep in mind that those conventional systems cause tens of thousands of fires per year). And that also means that unless there was a failure within the battery or some other problem with drive circuit, the fire cannot be attributed to the high voltage system of the car.

I still say that the problem will be traced to some conventional component that failed due the the fact that it was submerged in salt water for an extended period of time. No car should be expected to survive that, and the fact that so many did is impressive. The fact that some Karmas didn't is more of a reflection on how poorly the cars were engineered/built than it is on the nature of their power-train.

[Number 3]

Originally Posted by DGthe3

I know all about voltage and amperage and how batteries work. Amperage is a function of the voltage supplied and the resistance of the circuit, not a driving element of the circuit. The maximum amount a battery can supply has little to do with how much it actually supplies in a given circumstance. If the circuit needs 5 amps, the battery supplies 5 amps -not 60 amps (or whatever) it could supply. It will only do that if the circuit is needs 60 amps.

Now, back to the burnt down Karmas. While its true that the battery is in the 300V range, not every single component of the electrical system operates at that voltage level. In fact, about the only thing that does is the drive motors. Most of the remainder is at the same voltage as any other car. Afterall, it is an awful lot easier to bring down 300V to 12V (or 60 or 3.87 or 189) and use a standard component (like a power window motor) at a normal voltage than it is to redesign all those other components to run off of 300V. Consequently, the vast majority of the wiring on hybrids and EVs is no more dangerous than it is in a conventional car (and keep in mind that those conventional systems cause tens of thousands of fires per year). And that also means that unless there was a failure within the battery or some other problem with drive circuit, the fire cannot be attributed to the high voltage system of the car.

I still say that the problem will be traced to some conventional component that failed due the the fact that it was submerged in salt water for an extended period of time. No car should be expected to survive that, and the fact that so many did is impressive. The fact that some Karmas didn't is more of a reflection on how poorly the cars were engineered/built than it is on the nature of their power-train.

Not likely as the ignition was not on so you would have to believe that simply submerging a 12V battery would cause fires.

The 12V fires you are refering to are generally caused by a short that creates heat not simply 12V of current passing.

Now 300 V getting submerged? If not designed properly that can be a problem.

[DGthe3]

Originally Posted by Number 3

Not likely as the ignition was not on so you would have to believe that simply submerging a 12V battery would cause fires.

The 12V fires you are refering to are generally caused by a short that creates heat not simply 12V of current passing.

Now 300 V getting submerged? If not designed properly that can be a problem.

A battery itself might not fail, but something attached to it can. And we can't forget the fact that even with the ignition off, some systems are still drawing power. They're waiting in standby mode (computers, clock, remote locks, etc) but there is power. And these sorts of components are also the least likely to be resilient to salt water intrusion.

We can't forget that its not as if these cars got a little splash of rain water. They were submerged under salt water who knows how deep for hours. The combination of pressure (by water depth) and time would cause places that were never supposed to get wet to be surrounded by a highly conductive solution, then become encrusted with salt after the water receded. I cannot think of a more nightmarish scenario for electronics.

And yes, I am aware that its usually a short that causes a fire. In fact, thats what I'm counting on in this case. Salt water corrosion causing a short, leading to a fire.

Number 3, I am not an automotive engineer -you are, so please correct me if I'm wrong with this next part. The way I see it, the battery and high voltage wires for the Karma are going to be at least partially exposed to water in every day usage. The battery is mounted low, which means it'll get wet from road spray when it rains. Any reasonably competent engineer is going to take steps to seal the connections against water intrusion. I wouldn't be surprised if they make sure that when submerged its still fine. Thats just prudent engineering. But there are other electrical systems, the normal every day things, that are tucked away in spots that are supposed to stay nice and dry at all times. Probably dealing with some humid air, but not really anything more than that. As such, they might have a protective cover to guard against a bit of a splash (and to keep dust out), but nothing water tight because they aren't supposed to see anywhere near the amount of water to justify such measures. Consequently, those low voltage systems would be more prone to salt water exposure in a submergence event than the high voltage battery -its just too far beyond their design envelope.

[Captain Awesome]

Originally Posted by DGthe3

I know all about voltage and amperage and how batteries work. Amperage is a function of the voltage supplied and the resistance of the circuit, not a driving element of the circuit. The maximum amount a battery can supply has little to do with how much it actually supplies in a given circumstance. If the circuit needs 5 amps, the battery supplies 5 amps -not 60 amps (or whatever) it could supply. It will only do that if the circuit is needs 60 amps.

You almost have it right. We're talking about a deviation from normal operating conditions here and the results of the deviation. Obviously these cars don't "need" all the amps in the battery all at once under normal conditions. But if you're a fire rescue type guy and you're trying to cut some person out of a car in a hurry so they don't bleed to death or something, then you need to know that battery doesn't know you don't NEED 200A of current when your saw cuts through the insulation on that battery wire. The battery only sees a low resistance path to complete the circuit and it pushes as many electrons into that path as it can fit.

Now, back to the burnt down Karmas. While its true that the battery is in the 300V range, not every single component of the electrical system operates at that voltage level. In fact, about the only thing that does is the drive motors. Most of the remainder is at the same voltage as any other car. Afterall, it is an awful lot easier to bring down 300V to 12V (or 60 or 3.87 or 189) and use a standard component (like a power window motor) at a normal voltage than it is to redesign all those other components to run off of 300V. Consequently, the vast majority of the wiring on hybrids and EVs is no more dangerous than it is in a conventional car (and keep in mind that those conventional systems cause tens of thousands of fires per year). And that also means that unless there was a failure within the battery or some other problem with drive circuit, the fire cannot be attributed to the high voltage system of the car.

Since we know that a smaller diameter wire weighs a lot less than a thicker one, and that you can use thinner wires the higher the voltage goes, we can fully expect that there will be many common electrical parts running off high voltages in these so-called "efficient" cars. If not already in place, it will only be a matter of time before saving 3 pounds of wire will be the difference between being able to sell a car or having to take it off the market due to external pressures.

[Russell James]

That is probably the expected result. If it were a battery powered submarine, I'd expect no issues. But a high voltage device never intended to be submerged.... expect an event.

Ever see a transformer blow up? High voltage, lots of stored energy... shorts out. Kaboom.

Putting a car like that under water is pretty much shorting out everything. Shorting out that much stored energy is going to be a big event.

[midnighter]

Last week I saw a Tesla sedan, by the time I pulled out my cell cam to shoot a pic it took off making not one sound. I like noisy cars. Electric ones scare me.

[pyr0b0y]

Originally Posted by midnighter

Last week I saw a Tesla sedan, by the time I pulled out my cell cam to shoot a pic it took off making not one sound. I like noisy cars. Electric ones scare me.

Been seeing them more and more around town. (I work near Tesla). But those fiskers are damn sexy. I'm looking into getting one sometime next year. Great commuter for sure, plus work has electric charging stations!

[trewyn15]

Interesting...

At least I saw a set of good tail lights

[DGthe3]

Originally Posted by Autoblog

Port Newark Incident – Fisker Automotive Follow-Up Statement

On October 30, following Superstorm Sandy, several electric hybrid and non-hybrid cars from a variety of manufacturers caught fire and were damaged in separate incidents after flood waters receded at Port Newark (NJ), including 16 award-wining Fisker Karmas. Port Newark is one of the largest vehicle handling facilities in the U.S., and many thousands of vehicles of many makes and models were severely damaged as a result of the unprecedented flooding.

After a thorough inspection witnessed by NHTSA representatives, Fisker engineers determined that the damage to the Karmas was the result of the cars being submerged under five to eight feet of seawater for several hours that left corrosive salt in a low‑voltage Vehicle Control Unit in one Karma. The Vehicle Control Unit is a standard component found in many types of vehicles and is powered by a typical 12V car battery. This residual salt damage caused a short circuit, which led to a fire that heavy winds then spread to other Karmas parked nearby. There were no explosions as had been inaccurately reported. The Karma's lithium-ion batteries were ruled out as a cause or contributing factor.

The Fisker Karma meets or exceeds all safety requirements for markets in North America, Europe and the Middle East. Fisker Automotive is the leading manufacturer of luxury Electric Vehicles with extended range and will continue to develop and market vehicles that deliver an unmatched combination of style, performance and economy.

autoblog.com

[Captain Awesome]

They did a good job of blaming the Volt fires on other things too, and even had "help" in the cover up from the "watchdog" that's supposed to make safety rules. I do not trust the Praetorian Guards of the green agenda.