Battery smells

Your battery is being seriously overcharged. Turn the charger off and allow it to cool.  Do not continue to charge it.

This can occasionally be because the charger has become faulty and is putting out too high a voltage,  However the most likely cause is that the battery has developed a shorted cell. (the reduced voltage with a shorted cell means that the charger will output its maximum current indefinitely, causing the remaining cells to be overcharged and gas).

thank you i will take it back to the dealers for a check over.

If you have a multi meter you can do a basic , reasonably reliable test to check if the battery  has a shorted cell, by far the most likely type of failure in a case as you describe.

With the EHU not connected and nothing on in the caravan, measure the voltage across the battery terminals, ideally some hours off charge.

A healthy battery would read 12.7 upwards.

One with a shorted cell will measure about one sixth less, so of the order of 10.6, ie way below the 12.7.

One I had fail recently was just 9 volts.

My leisure battery has cracked, and discharged acid inside its housing box inside my motorhome, I have taken battery away from motorhome, and purchased a new one, but have not connected yet, as the smell inside the motorhome is unbearable, had door and window open for 2 days, but so far can't get rid of stench!

anyone able to give advice or help on this!

Thanks' Vic

Sulphuric acid = rotten eggs smell. We've had a similar event but not quite as bad. I think you can neutralise it with baking powder (sodium bicarbonate) but check first, it could be an unwanted chemical lesson. Good luck! 

i had one leak in a car once and used baking powder and water to wash down the battery box it was under rear seat in a vw beetle 1970s.