CRANKING OR DEEP CYCLE??????????????????

Synergist, i would personally choose a cranking. if your not using it too much or only a couple of time a year they are good because the charge alot quicker than a deep cycle. sure they will drain a little quicker too but hey your not gonna be using it that much anyway..............just my opinion

just type in grumpy..i mean Willem
was a thread generated back a few days ago which should help explain

Synergist.

The differance between cranking and deep cycle, so I was lead to belives is as follows.

Cranking batteries are designed and built to deliver a large amp delivery I.E. about 80 to 100 amps a short period of time, about 10 or so second, to start the engine and allow the alternator fitted to the vehicle to take up the load of poweri9ng the vehicle and replace the charge taken from the starting battery as quickly as possible, so as to be ready for the next starting cycle. This is why starting batteries are rated in CCA's ( Cold Cranking Amps) and not Amp/Hours.

Deep cycle batteries are designed and built to supply a constant "light current" over a longer period of time and this is measured in Amp/Hours. My 80 Amp/Hour battery is rates 4 amps @ 20 hours. If you take a higher level of current from the Deep Cycle battery it shortens the usage time considerably.
I.E. 8 amps per hour will only eaqual about 8 hours of use, not 10.

However, you should not discharge the battery to this level, At most you should only discharge to 50% of capacity and the recharge, and this will have a life limiting aspect on your deep cycle battery. A battery life is limited by the numer and depth of discharge/charging cycles. The deeper the discharge between charges, the lesser the number of cycles that you can achieve.

Most battery manufactures reccomend a discharge level of about 25% of capacity before recharging, to atain the highest number of cycles available for a deep cycle battery

Another point to remember is battery maintance. Regular cleaning, to prevent parasitic discharge between the terminals, topping up with disatilled or de-ionised water, (NOT TAP) and kept cool and well ventilated to disperse volitile gasses produced during charging.

Also, no not store the battery in a discharged state, as this allows the plates to sulphate and prevent adaquate recharging to full capacity, and thus slowly ruining it.

I would suggest reading a couple of battery manufactures sites re recharge cycles etc, and the site operated by MEGAPULSE, as this give a lot of informanion.

Cheers Nick.

Check post 5920

http://www.uuhome.de/william.darden/carfaq.htm

Something to look at with a deep cycle as second battery is WILL it start your motor, particularly a diesel, if the main starter battery is dead or discharged?
I feel it is great insurance to have two batteries either of which will start your motor. It is more vital than a few coldies in the frig. I have a much abused Delkor starter battery from which the frig has often been run before putting in an Exide Endurance as no2. It too has been abused & still comes up for more.

I believe unles you crank up your charging voltage to about 15 volts, you won't fully charge a deep cycle battery.

Synergist,
Should suit you this, they now have such a beastie as a hybrid battery which is a combination of both the deep cycle and the cranking battery, best of both worlds, I've got one seems to work so far, I've tried it winching and also for a couple of days o the fridge, the winching gave it a bit of a shock I think, still seemed OK, I've got 18 months left on the warranty, that's also good. Keep the shiny side up

Synergist,
I use 2 x 80a/h Delkor Deep Cycle Gel batteries wired in parallel with a Pirahna Electronic isolator & 80wt Solarex solar panel.

I camp at the one spot for many weeks, not days, and have to rely on the batteries to be able to deliver the power, I dont have to start the vehicle to recharge batteries.

It is 'horses for corses' if you are prepared to be continually running your vehicle to recharge your battery (s) then a crank battery will do for a weekend (maybe).
The hassle is when you go away for longer you will only have a few days power available to you.

You say "it will be used for a very minium" then the question is.....
is your minium a day or a week?

my choice would be to err on the side of positive power....
a .. Deep Cycle battery.. they are designed to be used continuously run the fridge etc.