Exploding Battery

Re: Exploding Battery (gadams)

You're not alone:

Mercedes, GM announce recalls
Battery problem in Mercedes C Class models; brake light trouble in GM sport utes
By Nedra Pickler / Associated Press

WASHINGTON -- Mercedes-Benz USA is recalling 65,000 cars after owners complained of exploding batteries, while General Motors Corp. is recalling 546,000 sport utility vehicles because the brake and hazard lights can fail.
Mercedes-Benz is asking owners of all 1998 and some 1999 C Class models to bring them to dealers so they can check the battery fluid. If the fluid is too low, it can expose electric plates and ignite gases inside.
"We're not necessarily going to be replacing them, in fact in most cases we won't be," said Mercedes-Benz spokesman Fred Heiler. "There is nothing wrong with the battery if it is maintained correctly."
At least five owners have reported that their battery exploded. One person was reportedly injured by spraying acid and battery fragments.
Mercedes-Benz dealers will put warning labels in the owner's manual and engine compartment saying the battery should be checked during every tune up.....

I've just got back from my garage refilling the OEM battery with distilled water.
Check your battery fluids every 10k.


[Modified by VW'ed, 4:50 PM 2-6-2002]

Re: Exploding Battery (sameero)

I would hope that your cables would have a tag on them. I know the ones my wife has now (my old ones) did.
IIRC, the order is:
1. + (dead)
2. + (good)
3. - (good)
4. ground (dead)

Re: Exploding Battery (idale)

Tox and idale make a good point. The order in which you connect the cables is not so important as what you do with that final ground connection.
This is the way I always do it:
1) Turn off all electrical accessories on both cars
2) Connect RED cable to + terminal on GOOD car (the cable color doesn't matter of course, the electricity doesn't know what color the handle is, but it's always wise to go with the convention).
3) Connect other end of RED cable to + terminal on DEAD car.
4) Connect BLACK cable to - terminal on GOOD car.
5) Connect other end of BLACK cable to a bare unpainted metal area away from the battery on the DEAD car. DO NOT connect it to the - terminal of the battery on the dead car. I find hood latches are usually good for this.
6) Start the DEAD car.
BATTERIES VENT HYDROGEN GAS. If you connect to the - terminal of the battery, you will get a spark. The spark can make the battery explode (remember fun with Hydrogen in high school chemistry?). An exploding battery will splatter your car and you with sulfuric acid, not to mention shrapnel from the battery case.

Re: Exploding Battery (sameero)

The objective when jumping a battery, is to prevent any sparks near to the 'dead' battery. Note: make sure you keep jumper cable ends in hand and insure that they are not touching each other or any other surface. First connect the positive lead to the dead battery positive terminal. Second, connect other positive lead to the 'active' battery postive terminal. Third, connect the negative lead to the negative terminal of the 'active' battery. And fourth, connect the remaining negative lead to a good ground location on the engine of the 'dead' battery (you may see a spark at the negative lead during this step). DO NOT CONNECT THE GROUND LEAD TO THE NEGATIVE TERMINAL OF THE DEAD BATTERY!.
Never start by connecting the positive lead to the good battery. If by chance you get distracted, and the ground leads find ground, your other positive lead will be 'hot' and by accident, might cause a spark around the dead battery. Rule of thumb, no voltage should be present when making the single connection to the dead battery.


[Modified by d2x/dt2, 6:40 AM 2-7-2002]

Re: Exploding Battery (d2x/dt2)

I stand corrected on my detail above. I've always avoided connecting to the negative terminal of either battery when jump starting, preferring simply to connect a good grounding point on either car. But connecting to the (-) terminal of the donor battery is preferred (probably to make sure of getting enough amperage to crank the dead car). Therefore, the last connection should be to the grounding point of the dead car. This should also be the FIRST connection broken, which may also produce a spark. Note that this grounding point can be anywhere on the dead car -- the farther from the battery the better.
As for the chemistry of batteries, here's a link to a quick explanation: http://www.hepi.com/basics/pb.htm
Electrolysis of water during charging (producing hydrogen and oxygen gases) is a normal side-reaction that is only dangerous when the normal chemistry of the battery can't keep up with the charging rate. That's why, when you have a battery on a charger, you need to vent to an open space and stop charging when all cells are bubbling. Any kind of super-fast charging must be done with great care.

Re: Exploding Battery (sameero)

My husband told me to NEVER jump start the Passat (2002) and so did the mechanic at VW because you can mess up the electronic system (the computer). He told me if I ever get stuck to call the mechanic (if I'm not too far, and I usually am not) and he'll come out or call roadside. Even though I know what I am doing, I will not go there.Just something to think about. I am soo Thankful that we have a great relationship with our dealer and mechanics.They are GREAT!!!!

Re: Exploding Battery (gadams)

Just a few more points to add on battery jumping. Make sure that the cars do NOT touch and that they are situated so that you can easily walk around them without yourself touching both cars at the same time. The negative ground system applies to the body and even though paint is an insulator, you never know when you might hit metal. This also dictates another good reason as to why to connect the +(dead) first. If you connect to the +(good) first and you have a stray ground connection either through you or touching cars etc. then your second connection to +(dead) will complete the circuit and you will get a spark.
One more word on the final connection -(dead). Yes it should NOT be to the - of the dead battery like people say. But also, when you connect it to an unpainted frame surface you should get a spark. In fact that is one way to tell that you have a good connection setup. Just don't let that spark through you. It's normal and tells you that you've done things right. Now if you're really good at it, you could make the connection with minimal spark, but there will always be some, though you might not notice it.

Re: Exploding Battery (mgan)

Did either your warranty or insurance pay for that, or were you stuck with it?