Charging a Prius Blamed for Starting Fire

Actually quit common than you think, even to maker of other brand cars. In the world of the exotics since people don't drive them everyday they are usually hooked up to a "tender", or "maintainer". (low amperage charger to keep the battery fully charged) Numerous cars fires have been started this way, but typically caused by a short somewhere, or a faulty battery.

People have been discussing this for years questioning if to leave the car on maintainer or not. But of course despite of these isolated incidences there are millions of them that's on the maintainer without any issue.

For me, I choose not to. So I have to force myself to drive it once a week.

 

Aftermarket nimh battery caught fire, we don't even know if it was the cause. Nothing to see here, but the sfist seems to think there is

Toyota Prius Accused Of Killing A Cat, Setting Fire To Condo: SFist

 

While a large enough NiMh battery when overcharged could go on fire but I doubt it would explode. However, a Li-ion battery's energy density is much higher than a NiMh battery pack and Li-Ion battery packs are an entirely different story. Overcharging a Li-ion battery can cause it to explode. One of the reasons - the Prius NiMh battery has a very long lifespan( normally >10 years) is that Toyota's on-board computer doesn't allow the battery to ever get above an 80% state of charge - the Prius computer works very hard to prevent the NiMH battery from being overcharged or undercharged. On of the reasons, the Prius Plug in has only an 11 mile range is that the Plug in's manages the Li-ion battery in the same way so Toyota prevents the Li-ion battery from being overcharged or undercharge - so I find it inconceivable that an unmodified OE Prius battery would explode or even catch on fire... However, the aftermarket Plug-in kits are a different story all together , Li-Ion battery systems like Enginer and Hymotion run their add-on Li-ion battery packs to very low levels [ e.g. 10% State of Charge(SoC) ] and top off the state of charge to their add-on battery systems during recharge to achieve the highest possible electrical only range for their kits. One of the reasons, the aftermarket Li-Ion battery packs have a limited lifespan - about six to eight years before needing to be replaced - is that the aftermarket PiP kits do allow for more than 80% of the state of charge to be expended before shutting down the Li-ion pack for recharging. During recharging, a battery pack will have a very very high load as it recharges from 10% to 50% of its rated state of charge - the heat and gas buildup created during this fast recharge phase can cause the battery canister or seal to fail. The recharging rate of a battery does not occur in linear fashion. Recharging from 50% to 70% state of charge is safer but it goes about twice as slow . Recharging from 70% to 100% takes about 50% of the remaining recharging cycle time and is very very slow process - normally a recharging system has a voltage level cut off switch that senses when the battery is at 100% SOC and this prevents overcharging which could cause the battery to fail or explode . By only allowing a battery to discharge and charging between 40% to 70% - the OE Prius battery not only recharges faster but its lifespan and safety is increased. However, the aftermarket Li-ion PiP kits has no margin for error in its installation or maintenance - this is very important. This incident looks like one of those add-on Lithium ion battery kits have failed. As Star Trek's Scotty might have said to Captain Kirk - She given you all she has, if you push her any further and she's goin' blow.

BTW: Inanimate objects like guns and and cars don't kill. It is the person who is controlling the gun or car that is responsible.

 

The NYT reported that the prius had was a 6.1 kwh nimh pack from plug in conversions, a California conversion company. It had a Brusa charger that pulls 8 amps 110V.

There is no point in speculating that a nimh can't start a fire, since they clearly can and have. Nor should we think that a limh battery with proper bms should explode or catch fire.

We still don't know if the car was the cause of the fire or the charger. Let's wait for the investigation for that. In every one of these OEM lithium fires we have the battery packs and chargers were not at fault. There is no reason to think the prius phv with the Toyota OEM lithium pack will catch fire or explode.

 

and the news writer of the SFist, what an IGNORANT !!!

To Walter Lee and the group
your technical explanation of the recharging process is very well made and to the point in certain cases.
I would like to add to your comments an specific omission, probably because of lack of experience.
The specific conversion used a larger NiMH battery replacement; it doesn't take to much to have a failing and unbalanced battery module in withing the string and while charging to have the polarity reversed because of its internal chemical reaction.
I have seeing them heat bulging and exploding like a .45 caliber ammo.
If we add to the equation a restricted container with one and probably more than one module failing, they burst into plasma arcing, melting their contacts and causing fire.
This cases are unusual but do happen and end up with a terrible consequence.
Despite of the damage the bursting in flames car did and the disruption of internal burning evidence, it will be very hard to point out the root cause of the starting point of ignition or fire being that it will be a melting pot of plastics, metals of different kinds and uzzing chemicals.

 

I don't recall any commercial NiMh based Plug in Conversion kits available for the 2nd gen Prius. In 2008 when I was looking at Plug in conversion kits for the 2nd gen Prius, the only commercially available kits that I found used Li-ion battery systems.

The fact that 8 amp and 110-120 volts- was being used only rules out a fire caused by the condo's electrical wires. The way Nimh battery cells are design don't exempt them from catching on fire but they don't normally have enough energy density to explode, but Lithium ion batteries have enough energy density to explode.

I think that the whole point of this fire - is that something did go wrong. The suspects being any aftermarket on-board electronics modifications to the Prius, the off-board recharging system and the aftermarket on-board battery.

 

The whole point of having an internal sensors and an inverter for each battery cell in your array of batteries is to prevent overcharging of each battery cell and to balance out the recharging process - to have anything less is suicidal - any electrical engineer worth his degree would heaven forbid do nothing less! One of the reason the Prius computer system is soo complex is that it monitors the *health* of each individual inverter and sensor per battery cell to prevent such a scenario from happening. Each cell contains only a fraction of the energy of the entire battery pack. When one cell pops from excessive heat and gas - the battery casing will rupture; however, I've never seen one explode.

I agree that the fire will destroy much of the evidence in that it will melt almost everything to nothing - however, if it was an explosion then there might be enough debris blown away from the initial blast to have enough clues as to the state of the battery seals, sensors, or casing.

The inverters are usually in a separate box than the battery so the inverter might still be intact.

FYI: the FAA fire investigations on the Boeing Dream liner jet passenger aircraft centers around using-including the very high energy density Lithium-Air-Ion Battery packs. Future Lithium Air Ion based vehicles have something to look forward too....

 

First I admire everyone who has the intellect and guts to experiment . . . it is something I do regularly. But sometimes 'bad things happen.' Often a learning experience, it is a risky, dirty job but someone has to do it . . . or we just sit cursing the darkness:

• Prius fuel exhaustion
• 1kW inverters
• E85 in Prius
• Type WS for NHW11 transmission

I'm sorry for their property loss, both personal and housing. But I admire pioneering work. Best of luck as they deal with the aftermath.

Bob Wilson

 

A quick google with the nyt information, gives some additional specifications.
Plug-in Toyota Prius conversion by PICC | ModernRacer Cars & Commentary

The PICC conversion also fakes out the prius software to stay electric. The ill fated conversion was done in 2010. I wonder if the 3 year warranty covers the fire. There are many things in a garage that can explode, all the car needed to do was catch fire. We should not blame the conversion until more information comes from the investigation though. The low amerperage and fact that he had been charging cars in that garage for 8 years makes the wiring in the condo seem unlikely though.

 

We do not know with certainty in this case of the burned Prius, but Plug In Conversions (PICC) was selling their larger conversion hardware with large Gold Peak NiMH batteries at certain point of their business activities.

 

here it is the latest new posted in the Calcars newscc
about Ron's vehiclea
bCalCars' first Prius, converted to plug in by advocates in 2004,
updated in 2010 with a commercial system, was destroyed in a fire on
Wednesday. It's a sad end for a vehicle that gave hundreds of public
officials their first opportunities to drive electric and helped
inspire a campaign that brought us the Chevy Volt, the Prius Plug-in
and other plug-in hybrids and extended-range electric vehicles. It's
also a huge personal setback for its owner, Ron Gremban, CalCars
Technology Lead.

(Shortly after it goes out on email, this posting will also be
viewable at http://www.calcars.org/news-archive.html -- there you can
add CalCars-News to your RSS feed.)

The New York Times story below, by Bradley Berman, founder of
HybridCars.com and PlugInCars.com, explains the situation. Because of
the extent of the damage, there's much we don't know and may never
know about the cause of the fire. Here are a few preliminary broad points:

* It's fortunate that no humans were injured, especially Ron's
partner, Lynne McAllister, who discovered the fire and notified the
fire department; it's very sad that one of their cats died and the
other is missing. And the damage to their home is a heavy financial
setback from Ron and Lynne.

* This incident has NO implications for mass-produced plug-in
vehicles. Ron's car used nickel-metal hydride batteries, the same
battery type used in the original Prius and in other conventional
hybrids for the past 15 years. Today's production PEVs use
lithium-ion batteries. This commercial conversion did not use the
current industry-standard J-plug found in all the fully validated and
tested cordsets in production vehicles.

* What happened can be put in perspective when compared to the
internal combustion industry's record, chronicled by the National
Fire Protection Association: from 2003-2007, an annual average of
287,000 vehicle fires, 480 civilian deaths, and $1.3 billion in
direct property damage. http://www.nfpa.org/categoryList.asp?categoryID=1123

* In 2004-2005, our message was that amateurs and engineers working
in a garage could show how we could have cars that plug in NOW, with
batteries that were "good enough to get started" and would improve.
We encouraged the media and the public to imagine how much better and
safer they would be when mass-produced by automakers. These
conversions drove home the benefits to drivers, the economy, the auto
industry, the environment, and national security. (This story is well
told in early news stories http://www.calcars.org/kudos.html and
http://www.calcars.org/early-news.html , and chapters in dozens of
books, especially in Sherry Boschert's "Plug-In Hybrids, the Cars
that Will Recharge America" http://www.calcars.org/books.html .)

* This first conversion and many dozens more completed through our
Open Source Prius+ project proudly announced that they got "100+MPG"
of gasoline, plus a few cents a mile of "cleaner, cheaper,
domestically produced" electricity. They and about 1,000 other
conversions by small companies had a giant impact. They helped reach
the goals of CalCars, the Electric Auto Association, Plug In America,
and others: raising awareness, getting opinion leaders the
opportunity to experience driving electric, and encouraging carmakers
to mass-produce all types of plug-in vehicles.

* 80,000 plug-in cars have been sold since the end of 2010
http://www.electricdrive.org/index.php?ht=d/sp/i/20952/pid/20952 .
And it's been clear for some time that the era of small-scale hybrid
conversions was drawing to a close. We still hope that more
companies will jump into a larger opportunity -- converting tens of
millions of internal combustion engines to plug in, an idea we
promoted heavily from 2009-2011
http://www.calcars.org/ice-conversions.html . And we still have much
to do to bring PEVs into the mainstream, through DrivingElectric.org
and other efforts supported by CalCars, EAA, PIA and allies.

* Finally, about Ron. He's a talented and resourceful engineer, a
good writer, and a smart strategist. CalCars, founded in 2002, got
its most important jump-start when he came on in 2004 and led the
conversion project and many subsequent programs. He devoted his life
to this effort from then until he got his Chevy Volt at the end of
2010. Due to budget constraints at CalCars, he was largely a
volunteer. Ron's costs in rebuilding his home and replacing damaged
possessions and his car will not be fully covered by insurance. We
have already received inquiries from people who would like to help.
If you would like to donate directly, please reply to this message or
write to sponsor (at) calcars.org .

Thanks for all the support and help this community has provided over the years.

http://wheels.blogs.nytimes.com/2013/03/07/fire-destroys-a-pioneering-plug-in-pr\
ius-conversion/

March 7, 2013, 6:00 PM

Fire Destroys a Pioneering Plug-In Prius Conversion
By BRADLEY BERMAN

A 2004 Toyota Prius that had been converted to run on grid-supplied electricity
caught fire at 6:30 p.m. Tuesday night in Corte Madera, Calif., according to The
Marin Independent Journal and other Bay Area news outlets. Nobody was hurt, but
the fire killed a cat and caused about $250,000 worth of damage to the owner's
condominium.

The cause of the fire was unknown.

The vehicle, which had about 50,000 miles on the odometer and was owned by Ron
Grembam, played a crucial part in the history of plug-in electric vehicles. In
2004, Mr. Grembam said, it was converted to use a plug -- and an added battery
pack larger than the one provided as standard by Toyota – so that it could run
for a number of miles purely on electricity. At the time of the conversion,
Toyota and other automakers were not making plug-in hybrid cars and expressed
doubt about the technical and market viability of the technology.

"The message we had from the start was that if a group of amateurs and engineers
could make the technology work in a garage, then the major automakers could make
it much better and safer," said Felix Kramer, the founder of CalCars, the
plug-in car advocacy group that organized the conversion and a subsequent
campaign to get car companies to produce electric cars and plug-in hybrids. In
an interview Thursday, Mr. Kramer added, "This unfortunate fire unequivocally
has nothing to do with today’s production plug-in hybrids."

Nearly 40,000 plug-in hybrid vehicles were sold in the United States in 2012.
The market includes the Chevrolet Volt, Toyota Prius Plug-in Hybrid, Ford C-Max
Energi and Fisker Karma. Honda and Ford will introduce new plug-in hybrids this
year.

Mr. Grembam, who is also associated with CalCars, could not explain the cause of
the fire, which had occurred while the vehicle was being charged. "It's not
obvious," he said. "The car exploded and apparently destroyed all the evidence."
The vehicle was using a $5,000 Brusa charger plugged into a 120-volt outlet and
was able to pull only about eight amps, Mr. Grembam said. "That shouldn't be
enough to overheat the battery pack. That deepens the mystery."

The fire was controlled in about 30 minutes. The exact cause is being
investigated by the Corte Madera Fire Department, Mr. Grembam said.

The Prius was originally converted by CalCars to use grid-supplied electricity
in 2004. In 2010, the vehicle's plug-in system was replaced by equipment
supplied by the Plug-In Conversions Corporation of Poway, Calif., near San
Diego. In the conversion, the existing batteries were replaced with a
6.1-kilowatt-hour nickel-metal-hydride pack, as well as a charger, control
electronics and a plug. The conversion was intended to increase fuel efficiency
above 100 miles per gallon. Since 2008, Plug-in Conversions has performed about
70 without any problems, said Kim Adelman, the company's chief executive.

Mr. Grembam said: "This incident very well might make a dent in aftermarket
conversions. It would give anybody pause. But I'm hoping it doesn't affect the
market for O.E.M. plug-in vehicles."

He said that major car manufacturers use large teams of engineers to make sure
every safety factor is considered, but it's more challenging with one person or
a small team. "It's possible for things to get missed," he said.

-- -- -- -- -- -- -- -- -- -- -- --
Felix Kramer , Founderout alcars alcars-news· News From CalCars on Plug-in Hybrids
about Ron's vehicle

 

maybe the cat bit the cord

 

On this note, some of you may recall PHEV mod under way, Bristol, UK. | Page 16 | PriusChat and PHEV mod under way, Bristol, UK. | Page 17 | PriusChat.

 

I wonder if there is information in the Prius' black box recorder that would help identify the cause of the fire?

 

I just saw this on Prius page on Facebook. Is this related?
Photos of Toyota Prius | Facebook

 

Doubtful. I think the "black boxes" you refer to are event data recorders. No crash happened here.

No, that's a Gen 1 (01 to 03) Prius sitting outside. The one in this thread is a Gen 2 (covers 04-09 model year) w/non-Toyota modifications to add plug-in capability and additional batteries. See earlier posts.

 

That's what's funny. Hook up a 12v wet cel battery charger to your car battery, burn down the house, and it doesn't make the back page of the obit's. Electric fire via the garage fridge, table saw, window AC - you name it ... no big deal, it's not news. But if your home's faulty wiring burns up while your PiP is charging (factory or home made) WATCH OUT ... it may end up making the front page.
Burn down your house via the 10 gallons of gas in the tank? Same thing.

 

Candles are a huge cause of home fires. Stay away from them!

 

Thanks for your clarification. It also turned out to be the car with a salvage title. Phew.