DEEP CYCLE BATTERY is it any good

As long as it was ok to start with and was stored fully charged it is probably ok.
Suck it and see...give it a good charge and check it with a hydrometer. If it checks out try it with the fridge.

Hi peter in sa, I take it you have your paj back on the road, if so next time you know you are going for a good drive ( an hour at least ) just put the deep cycle back in the paj and when you get back put a load on on it, a fridge say, and see if it runs it for a while.
If it does not go flat after say 10 minutes or so then it’s probably OK but as to how much capacity it has as against its original storage capacity and operating life left, only time will tell.
Cheers.

I was always led to believe that a deep cycle battery should be flattened regularly to give it a longer life. You can buy gadgets to leave in the cigarette lighter to slowly discharge the deep cycle battery when it is left sitting for a while.
It is normal batteries that shouldn't be flattened and recharged frequently.

Wet cell batteries, deep cycle or otherwise, shoud never be discharged below about 50%. It can shorten their life dramatically.
My recommendation is that you invest in a quality multi-stage "smart" battery charger and make sure you store the battery fully charged.
These chargers cost upward of $350.00 but but IMO worth every cent.
I have just returned from a big trip and have a deep cycle battery in the car and one in the caravan. The last leg of the trip was Forster to Wollongong without stopping.
When I put my 7A Cteck (Bainbridge Technolies) charger on the van battery it came up to about 80% charge in about 8 hours but it was about 48 hours later before ot indicated FULLY charged and went to maintenance mode. It is quite safe to leave the battery connected in this mode indefinitely as the charger has smarts to deal with this condition.
The point of this story is that you will never fully charge your battery from the vehicle's electrical system no matter how long you run the car. The best seems to be about 80%. I also think on a long trip, driving and camping with the battery not being charged properly results in less and less capacity available as time goes by.
If mains is not available it seems Solar with a smart regulator or a quality generator that produces 240V compatible with a "smart" battery charger is the way to go but that will cost about $1300.00. A lot of generators are not sutable to run mains operated battery chargers.

okay, there's lots of talk here about extracting the most from deep cycle batteries, how to correctly charge for longevity etc. Personally I don't give myself any heartache. I have excess capacity and I just thrash the hell out of it if I have to and buy a new one every year. At $130 or so I just aint gonna worry about it.

Hi Mad Dog, your way of looking at it is actually the most economic way of getting the capacity you need.
You can buy all the fancy products you want, but by the time you add up the cost of all these EXTRAS you could have bought another battery of the same size, doubling your capacity and still have more money in YOUR pocket but unfortunately there are too many sales people out there who should know better but are more interested in making more out of customers who have come along to them thinking that these salesmen will givet honest solutions to meet the customers needs. Not so.
More battery capacity and the use of good heavy battery cables will solve 99% of needs and problems that most people come across.
Cheers

Lots of info here some a bit too technical for the average me but there is enough to get a relly good grasp on batteries.

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