Battery Gas

[Nicholas123]

I spent yesterday trying to resurrect my old battery by charging it in the kitchen & the Carbon Monoxide alarm went off twice & before I went to bed my chest was congested.Coincidently,I have found the gas alarm on my boat always goes off if I leave it on.So putting two & two together is it the battery acid fumes that are doing it?

 

[Mistroma]

My brother-in-law used to have a golf cart and I remember a similar problem. I think that I found out that some CO detectors are sensitive to hydrogen, even at very low concentrations.

Hydrogen will tend to rise upwards and I can imagine that it might be a problem if you have a CO alarm nearby. The detector is sensitive to concentrations of hydrogen that are around a similar level to concentration of CO needed to trigger an alarm. So seems feasible given you history of alarms.

I've never noticed it on my boat. However, the batteries are port side in aft cabin and cooker is in saloon on starboard. So my alarm is forward of the cooker and far from the battery box.

Update: I just did a quick search on detector cross sensitivity and found several documents. The link below indicates alarm threshold of 150ppm CO and 200 ppm hydrogen. Always good to find some evidence to back up my failing memory.
http://www.gasdetectorsinc.com/sellsheets/remotesensors/HIC-822-RS-A_datasheet.pdf

 

[john m]

The gas alarm started on my ladt boat after about 3hrs running i thought it was a fault as the gas was off i pulled the wire of at the time but in hindsight this was mad prety mad

 

[Nicholas123]

My brother-in-law used to have a golf cart and I remember a similar problem. I think that I found out that some CO detectors are sensitive to hydrogen, even at very low concentrations.

Hydrogen will tend to rise upwards and I can imagine that it might be a problem if you have a CO alarm nearby. The detector is sensitive to concentrations of hydrogen that are around a similar level to concentration of CO needed to trigger an alarm. So seems feasible given you history of alarms.

I've never noticed it on my boat. However, the batteries are port side in aft cabin and cooker is in saloon on starboard. So my alarm is forward of the cooker and far from the battery box.

Update: I just did a quick search on detector cross sensitivity and found several documents. The link below indicates alarm threshold of 150ppm CO and 200 ppm hydrogen. Always good to find some evidence to back up my failing memory.
http://www.gasdetectorsinc.com/sellsheets/remotesensors/HIC-822-RS-A_datasheet.pdf

If I had lit a match would there have been a bang? Considering the way I was gasping for breath & the volume of my bungalow I can't help thinking this whole problem should be flagged up more significantly.

 

[VicS]

If I had lit a match would there have been a bang? Considering the way I was gasping for breath & the volume of my bungalow I can't help thinking this whole problem should be flagged up more significantly.

The link indicates for that particular detector that the alarm for hydrogen sounds at 200ppm. The lower explosive limit (LEL) for hydrogen is 4% (40,000ppm) So no probably not because the alarm would be triggered at ¹/₂₀ of the concentration at which ignition would occur.

Neither carbon monoxide nor hydrogen would have been responsible for you gasping for breath. A mist of sulphuric acid droplets carried into the air is IMHO a more likely cause.

 

[Scubadoo]

Interesting, never heard of that and thanks for the warning. But for me I would never charge batteries in the house, only the garage where it is ventilated, I would also worry about acid escaping etc.

 

[NormanS]

That is also one of the better reasons for having a (flameproof) extraction fan for your battery compartment. More particularly if you are marina based, and using a mains charger, it makes sense to run the fan for acouple of minutes prior to starting the engine.

 

[little shack]

Don't be too sure about the hydrogen not going bang as I left a battery on charge on my old landrover in the position it was stowed.normal charge left the window open to ventilate,when i returned to reconnect it was dark. While reconnecting the spanner shorted the battery + blew the end of the spanner of the end of my fingers nails of two fingers and me over the neighbours fence

 

[prv]

That is also one of the better reasons for having a (flameproof) extraction fan for your battery compartment.

As I was tracing the plumbing in the new boat, I came across a "mystery green hose" running from a skin fitting in the topsides. The boat has a lot of interior mouldings so it's not always easy to trace where things go, and I lost this pipe where it disappeared into the plastic. A couple of weeks later I spotted it where it reemerged into the battery locker, branching into three small clear tubes. Clearly it is a battery gas vent, with the three tubes designed to plug onto the vent spigots found on some batteries. The batteries I inherited have no such spigots, but I will make sure any new ones do, and use them.

Pete

 

[VicS]

Don't be too sure about the hydrogen not going bang as I left a battery on charge on my old landrover in the position it was stowed.normal charge left the window open to ventilate,when i returned to reconnect it was dark. While reconnecting the spanner shorted the battery + blew the end of the spanner of the end of my fingers nails of two fingers and me over the neighbours fence

This is the reason that you should disconnect the negative first and reconnect it last.. Its relatively unlikely that anyone would short positive and negative together although not impossible if you try hard enough.
What is easy to do is to short positive to the body work. If the negative is connected a major short is the result with the danger of exploding any local accumulation of hydrogen and/or the battery. If the negative is not connected there is no danger.

 

[Seajet]

My boat has a vent tube from the battery compartment, labelled ' hydrogen - no smoking ', which seems a good precaution, even better it was a good excuse to stop my ex-wife smoking in the forecabin, a win / win for me !

 

[William_H]

Definitely worth having a sealed battery box with inlet and outlet type ventilation. Especially so with modern fast charge type regulators. A small computer type fan could be used to provide positive ventilation to outside. olewill

 

[prv]

Definitely worth having a sealed battery box with inlet and outlet type ventilation. Especially so with modern fast charge type regulators. A small computer type fan could be used to provide positive ventilation to outside. olewill

Seems odd to set up explicit precautions for dealing with flammable gas, and then run it through a potential source of sparks...

Pete

 

[Nicholas123]

Don't be too sure about the hydrogen not going bang as I left a battery on charge on my old landrover in the position it was stowed.normal charge left the window open to ventilate,when i returned to reconnect it was dark. While reconnecting the spanner shorted the battery + blew the end of the spanner of the end of my fingers nails of two fingers and me over the neighbours fence

Struth,makes me wonder how close I came to blowing the roof off my bungalow.I shall take this much more seriously now,thanks.

 

[charles_reed]

Don't be too sure about the hydrogen not going bang as I left a battery on charge on my old landrover in the position it was stowed.normal charge left the window open to ventilate,when i returned to reconnect it was dark. While reconnecting the spanner shorted the battery + blew the end of the spanner of the end of my fingers nails of two fingers and me over the neighbours fence

Ah! Landies always were dangerous little beasts.

 

[Mistroma]

Seems odd to set up explicit precautions for dealing with flammable gas, and then run it through a potential source of sparks...

Pete

I don't think that the fan should be sucking air from the battery box.

My setup has a fan with a brushless motor mounted low down, leading slightly uphill to just above the middle of the battery box. It blows across the box to a vent non the other side and tubing leads upwards to vent close to deck level near the stern.

I worked out the battery box volume with batteries in place and the fan moves much more air than required to keep below hydrogen's lower explosive limit. I'd need to check the rate of hydrogen evolution again to get the figures but it wouldn't become a problem under reasonable circumstances.

It seems to be safer than leaving the box unvented. I imagine that William_H has a similar setup as I think my installation is the usual way of putting in forced ventilation.

 

[johnphilip]

My boat has a vent tube from the battery compartment, labelled ' hydrogen - no smoking ', which seems a good precaution, even better it was a good excuse to stop my ex-wife smoking in the forecabin, a win / win for me !

Was it your goodself who drove her to needing a smoke?

 

[Seajet]

Was it your goodself who drove her to needing a smoke?

Well, armed with hindsight I wish I could claim anything which may upset the witch, but I'm afraid I can't take credit for that, she already had that disgusting habit.

Maybe I could have got her to take up walking the plank...