Battery and rotten eggs?

I used my dump trailer yesterday. I charge the two 12v deep cycle batteries by connecting them to the tractor battery, while I using the trailer. I idle the engine on tractor when dumping. The charging current never exceeds 15 amps. So my trailer batteries don't really get totally drained.

I put my trolling battery in parallel with trailer battery, because the trailer battery is getting old.

Last night I put a 15 amp craftsman smart charger on the two batteries. My battery minder was being used at another location. Well this morning the charger never shut off, only 5 amps, and the old battery was warm and smelled like rotten eggs for the first time. The newer battery, the one in parallel with the older one, wasn't warm or smelling.


I always thought batteries smelled because they were over charged. So how can one battery be overcharged while the other one isn't? The charger was actually connected to the good battery. Don't see how that would makes a difference. Electrolyte levers are good in both.

BTW, if this battery dies, it will be the first one in 4 years. 4 years ago I purchased a batteryminder 12348 charger. Guess in the future I won't use the crapsman dumb charger unless I connected it to a timer.
George

Bad cell on your smelly battery? Shorted cell would force other cells to overcharge. Best take it to a competent battery dealer and have them check it on one of those newfangled electronic whizbang testers.

Beats me other than the one that stinks is bad... BTW took this pix yesteday of the solar charger I installed on my car trailer. When I installed the charger 60 days ago the bat was @ 11.50 volts. It took it 30 days to get it to 12.20 volts and 60 to this point 12.67. Its a $19 Coleman solar charger. The charger is disconnected I am reading off the battery...

Cant say fer sure, two can be wired in parallel yet one draw more current then the other of course. Even only one bad cell can be emitting excess gas, rotten egg small is hydrogen sulfide right??

John T

the smell of rotten eggs is the surfer gas as the battery is charging the Sulfuric acid give off this smell when it heats up aery long as the battery has not gone dry they should be ok. refill the cells and you should be ok.

Yup, hydrogen sulfide.

Hobo,NC,
Where I live having a battery and solar charger
outside is asking for someone to steal it. I park
my dump trailer inside pole barn along with
anything else I don't stolen. Barn has an alarm
system that goes off in bedroom. I made sure the
word is out too. So far So good.

I like the idea of my batteryminder charger. It
never overcharges, then desulfates before it goes
to the trickle mode. The battery minder only takes
a day or two before it's on trickle mode. Then it
gets moved to another battery.

Don't think solar can defulfate, can it?
george

JohnT,
I remember what hydrogen sulfide smells like form my college days. Used it in chemistry lab all the time. Made my own with hard boiled eggs and beer.

The reason I posted this is I can't figure out why one battery smells and the other didn't?

It only takes but 3 or 4 days for the batteryminder to charge and desulfate the pair. Next time, I'll wait to charge with a good charger.
George

Different batteries, different technology, different full charge rate. If the batteries are not the same style and age they probably should not be charged in parallel.

BatteryMINDer does make a solar powered charger / desulfator / maintainer. Spendy little devil though at $150.

May not have been a good idea to let that little solar panel take two months to recharge a dead battery.

That's two months for a less than full charge battery to become sulfated.
Solar BatteryMINDer.

On my semi, when one of the three batteries would emit fluid and gases it was the bad one. Bad or shorted cell in the battery, replaced and all was good.

I have seen 100's if not thousands of bad battery's when one gives off a foul order its bad no need to ware out a good battery charger mess'n with it... They also will fume out the bad cell most of the time were you will see it cap off bat under a load and the water it it will be cloudy looking... I have overcharged my fair share of battery's its not the same sicking smell a bad bat gives off....

If you had brought a 500 amp carbon pile load tester there would be no doubt...

I bet you are right. I'll do a hydrometer test and find a bad cell.

My battery conductivity testor shows the 2 batteries produce 1000+ cca.

If the smelly one had a shorted cell, the other 5 would get too much voltage and produce HS.

Never charge batteries in parallel.

Dean

My battery conductivity tester shows the 2 batteries produce 1000+ cca.

I don't think you are gonna be a happy camper... They have been proven to pass a bad bat...

"I have seen 100's if not thousands of bad battery's when one gives off a foul order its bad no need to ware out a good battery charger mess'n with it."

DITTO, HOBO.

A failed/sulfated battery STINKS, and even CHEAP George will save time and aggravation if he follows your sage advice!

It may not but I did it out of curiosity ... Worst case I can afford a new battery.. It did pass a load test with in reason prior to installing the solar charger if it had not I would have not wasted my time fudgen with that battery......

I don't think letting a battery sit for two months without a full charge is a good idea either. I read that undercharging is as bad as over charging.

I'm convinced that some chargers, like my sears 15 smart charger may be one of those chargers.

I may just invest in another batteryminder at around $150. Pay for a good charger or pay for replacement batteries.