Battery Charging Rotten Eggs!
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Joined: Mar 2005
Posts: 85
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From: Pittsburgh PA
Battery Charging Rotten Eggs!
The vette has been parked for about 2 months now for the winter and has had a battery tender/trickle charger on it for the 2 months. I went to the garage where i am storing it and imediately noticed the smell of rotten eggs, but didn't know why or where it was coming from.
I took off the charger and went to start the car, the lights came on and guages lit up, but when i started it, nothing happened...just a lot of clicking. I went to check the battery and noticed that the rotten egg smell was at the battery, plus the battery was warm. I figured the heat was form the charger and didn't think anymore of it, but knew something was wrong from the smell.
I let it go for a few days and came back and the battery was DEAD. I tried to jump form my other car w/ cables and again all the lights came on and it read 14 volts, but couldn't start the car. After taking off the jumper cables, battery was dead imediately.
I'm assuming that the battery is fried and i need to replace it, but should i look at anything else first? Anyone else have trouble with a battery tender?
I took off the charger and went to start the car, the lights came on and guages lit up, but when i started it, nothing happened...just a lot of clicking. I went to check the battery and noticed that the rotten egg smell was at the battery, plus the battery was warm. I figured the heat was form the charger and didn't think anymore of it, but knew something was wrong from the smell.
I let it go for a few days and came back and the battery was DEAD. I tried to jump form my other car w/ cables and again all the lights came on and it read 14 volts, but couldn't start the car. After taking off the jumper cables, battery was dead imediately.
I'm assuming that the battery is fried and i need to replace it, but should i look at anything else first? Anyone else have trouble with a battery tender?
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Joined: Mar 2005
Posts: 85
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From: Pittsburgh PA
nope, never checked it....never even thought about it. Unfortunately the area in the garage where it's parked has very little light, so i will need to get a work light and plug it in to see.
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Joined: Mar 2005
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From: Pittsburgh PA
it was set on a 2 amp, 12 volt to trickle, so it shouldn't have been "overcharging" i don't think.
let me ask another question while we are on this subject, i have never had to use a charger, but in reading the instructions it said to attach red to the red on the battery and then the black to the frame or a metal object, i attached to the frame in the wheel well...any suggestions on a better place, maybe it wasn't a good enought ground?
let me ask another question while we are on this subject, i have never had to use a charger, but in reading the instructions it said to attach red to the red on the battery and then the black to the frame or a metal object, i attached to the frame in the wheel well...any suggestions on a better place, maybe it wasn't a good enought ground?
Drifting
Joined: Jun 2005
Posts: 1,426
Likes: 1
From: brookville pa.
charger
evo if your charger is on all the time, you might want to get one that shuts off when battery is at full charge. i have a sears one works great it has a light on it to tell you when bat is full when the other light[red] comes on then it is charge mode. you prob fried you bat. geo 
also these cars dont like to be jumped better off to just buy a new battery and make sure its fully charged if you get a spike while jumping some guys say it will ruin your ecm
also these cars dont like to be jumped better off to just buy a new battery and make sure its fully charged if you get a spike while jumping some guys say it will ruin your ecm
Last edited by geogolf; Jan 15, 2007 at 02:53 PM.
Race Director
Joined: Jul 2004
Posts: 16,795
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From: Lake Havasu City, AZ
What you are smelling is Hydrogen Sulphate ( H2 SO4) it is the smell of rotten eggs.
When a battery sites a long time and drains the Sulphuric acid reacts with the lead plates and creates a coating of lead sulphate on them.
when you charge a normal battery Hydrogen gas is given off . that is why you don't make the last connection at the battery when jumping a car... you don't want a spark near a source of hydrogen (KA BooM)
If your battery has a coating of lead sulphate on the plates, sticking it on the charger will evolve Hydrogen Sulphate Gas rather than hydrogen... hence the smell.
A lightly sulphated battery can be reversed... a heavily sulphated battery is toast.
When a battery sites a long time and drains the Sulphuric acid reacts with the lead plates and creates a coating of lead sulphate on them.
when you charge a normal battery Hydrogen gas is given off . that is why you don't make the last connection at the battery when jumping a car... you don't want a spark near a source of hydrogen (KA BooM)
If your battery has a coating of lead sulphate on the plates, sticking it on the charger will evolve Hydrogen Sulphate Gas rather than hydrogen... hence the smell.
A lightly sulphated battery can be reversed... a heavily sulphated battery is toast.
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Team Owner
Joined: Mar 2001
Posts: 54,124
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From: Cincinnati, Oh USA
Most likely you had a cell short and your trickle charger then charged the battery continously at 2 amps which overcharged the battery and got rid of the water in one or more cells. This increases the sulfuric acid concentration and continued charging makes for hydrogen sulfide gas which smells like rotten eggs. Replace the battery and buy a battery tender. 2 amp battery chargers are ok, but are not ok to leave on a battery for long periods. You can buy an interval timer and use it to charge your battery once a day for its minimum interval, usually 15 mins or even an hour won't hurt.
Last edited by jfb; Jan 15, 2007 at 06:47 PM.
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
sulphur
the atmosphere that your car is sitting in is very corrosive.
If you can smell it, all of your car is in it.
The best thing you could do is wipe it down with a towel and glass cleaner--- the whole car. don't let it sit there for 3 more months with that corrosive battery fog all over it.
your paint will go bad, and all of your aluminum parts will look like you left them out at the beach for a year.
Your interior will not last very long withut cleaning that stuff off of everything u can.
If you can smell it, all of your car is in it.
The best thing you could do is wipe it down with a towel and glass cleaner--- the whole car. don't let it sit there for 3 more months with that corrosive battery fog all over it.
your paint will go bad, and all of your aluminum parts will look like you left them out at the beach for a year.
Your interior will not last very long withut cleaning that stuff off of everything u can.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
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From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Just a tidbit of info-- that gas not only stinks, but if you make a spark it can explode. Hydrogen. Mkae sure you shut off your charger before you unhook it..
Safety Car
Joined: Sep 2002
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From: The reason time exists is so everything doesn't happen at once
it was set on a 2 amp, 12 volt to trickle, so it shouldn't have been "overcharging" i don't think.
let me ask another question while we are on this subject, i have never had to use a charger, but in reading the instructions it said to attach red to the red on the battery and then the black to the frame or a metal object, i attached to the frame in the wheel well...any suggestions on a better place, maybe it wasn't a good enought ground?
let me ask another question while we are on this subject, i have never had to use a charger, but in reading the instructions it said to attach red to the red on the battery and then the black to the frame or a metal object, i attached to the frame in the wheel well...any suggestions on a better place, maybe it wasn't a good enought ground?
I use a battery tender on my 69 and the directions say the same thing. The problem with a C3 is that the battery is behind the driver's seat and there's no way the negative lead will reach the frame or some other ground, so I connect it to the negative post on the battery. I call that warning "enginering by lawyers" It's the same mindset that puts labels on step ladders telling you not to stand on the top or the fold-out shelf. Basically the disclaimer is there to protect the manufacturer from lawsuits brought by idiots.
