Gas detector and battery boiling

[concentrik]

The first thing was swmbo noticing a slightly nasty niff... then the gas alarm going off sporadically. Not LPG though, we eliminated that. Then noticed that the battery charger had been reading 14.2v for longer than normal (usually settles to 13.8v within an hour or so). Don't recall what made me look at the batteries, but glad I did, because one was hot...like very hot. After carefully disconnecting and moving it shoreside the charger was back to normal, the gas alarm was quiet and swmbo was able to say, told you so.

I didn't know that a gas detector could sense products of a faulty battery but I'm glad we didn't just think they were false alarms. Next addition will be a battery temperature alarm. The charger doesn't have one (I know some sense batt temp for charging control, but an over temp alarm?) so I'm thinking a simple process alarm.

 

[pmagowan]

The ctek chargers automatically reduce output if the temperature sensor detects high temperatures.

 

[cooperwood]

hi.. I am not expert but i think false alarm detect because of the high voltage.I generaly reset my detector when it show false alarm.

 

[VicS]

The first thing was swmbo noticing a slightly nasty niff... then the gas alarm going off sporadically. .

A battery being overcharged will be giving off hydrogen ( and oxygen) The hydrogen ( or any other flammable gas) will trigger the gas alarm. They are not specific for lpg although the calibration of the alarm point will be for lpg.

 

[Corribee Boy]

An overcharging battery can also give off Hydrogen Sulphide - poisonous 'rotten egg' gas, which might explain the smell - and possibly the detector picked that up?

 

[GHA]

Then noticed that the battery charger had been reading 14.2v for longer than normal (usually settles to 13.8v within an hour or so). Don't recall what made me look at the batteries, but glad I did, because one was hot...like very hot.

Very hot at 14.2v ? Doesn't sound right.

 

[RichardS]

This thread is rather old but may be concentrik is still trying to resolve the problem?

Richard

 

[concentrik]

This thread is rather old but may be concentrik is still trying to resolve the problem?

Richard

Old but still in my mind... the battery was faulty - as soon as I removed it the charge voltage returned to normal and the smell stopped and the alarm stopped.

GHA: 14.2 is the usual with our setup (Numax, 240AH) and sometimes it is 14.8. We have a dual system though, the batteries on charge are totally separate from the boat 12V on shorepower, which is when we noticed the prob. I (probably) incorrectly replaced just one batt some time ago so the batts were 'new' and '2 yrs old'. Both the same age now though with a temp sensor stuffed between them.

 

[VicS]

This thread is rather old ................
Richard

rats!

An overcharging battery can also give off Hydrogen Sulphide - poisonous 'rotten egg' gas, which might explain the smell - and possibly the detector picked that up?

given that the threshold of smell is < 0.1ppm and that the LEL is about 4% ( one would assume that an alarm might sound at about 25% LEL) there would be a very strong, overpowering, smell of H₂S by the time the alarm sounded!

 

[GHA]

GHA: 14.2 is the usual with our setup (Numax, 240AH) and sometimes it is 14.8.

It was more a surprise at the battery getting hot at a relatively low voltage. Explained by a faulty batt.

I use 15.1v for bulk which ends up at 14.8v at the batteries or a touch more near the end of bulk - that's enough to set off the CO alarm but won't heat the batteries much. Though a gas soldering iron will set off the alarm as well.

Nice to know it's working