Battery longativity

Battery longevity is MEASURED by the number of charge/discharge cycles they go through. Of course BETTER batteries will withstand many MORE cycles than cheaper batteries but in BOTH cases their life will be dependent on the number of cycles even when they are different numbers. IN other words, keep them fully charged as much as possible and avoid very DEEP discharges whenever possible. When you are dry camping it is better to charge battery bank each day than to go two or three days before charging.
Good luck / Skip

I will run my battery bank of three GP24 85Ah batteries down to around 12.0VDC when camping off the power grid overnight which is very close to being 50% state of charge. Then I will connect my trailer 30AMP Shore power cable to my 2KW Honda Generator 120VAc receptacle using a RV30A-15A long adapter the next morning when allowed to run my generator.

This will allow my smart-mode converter/charger then charge my batteries up to around 90% state of charge in as little as three hours generator run time. The rule of thumb for me is to have around 20AMPs of charge current available for each battery so my PD9260C 60AMP Smart-mode converter/charge works just fine for this. My three GP24 batteries initial draws about 52-54AMPS of charge when hit with 14.4VDC charge voltage then idles back as the charge continues to slowly bring the batteries back to their 90% charge state. When they get back to 90% charge state I can expect the specified performance all over again for the next next day/night run off my batteries without doing harm to them.

I can do around 10-12 of these 50% to 90% charge cycles before I should do a full 100% charge cycle which will take around 12 hours of generator run time. Otherwise I will start doing harm to my deep cycle batteries. Since most camp grounds don't allow you to run a generator this long at one time this is usually when we come back home off the camping trip.

I have been using my GP24 85AH batteries going on five years and they are just now starting to fall back on staying performance. When constantly connected to my PD9260C converter/charger it will automatically do a Equalize Mode of 14.4VDC every 21 hours for a period 15-minutes to prevent stratification. Also the normal output of 13.6VDC will idle back to 13.2VDC when no current is being drawn to keep from gassing the battery plates. Having the right smart mode converter/charger unit automatically takes care of your batteries. I would still check the water levels on the fluids on a scheduled basis to make sure all is ok.

We are very successful camping off the power grid using our 255AH battery bank capacity. We operate all of the 120VAC items we want to use as well as the 12VDC items directly connected to the battery bank. This of course does not include using the air conditioner or high wattage microwave use. This is very much of the same thing we do when camping at the electric camp sites on shore power.

It takes good planning to be successful at it...
Roy Ken

Hi,

No. The shallower the discharge the longer the battery bank will last--provided that it is recharged to 100% as soon as is humanly possible after each use.

One result of adding a solar system is much longer battery life.

Wishbone51 wrote:
Deep cycle batteries can go all the way down, correct?

No battery should ever get fully discharged. Deep cycle batteries have thicker cells, deeper cases to prevent shorting, and a couple other differences from 'starting' batteries, but even they cannot handle a full discharge without damage. They are designed to be able to withstand many more cycles and recharges, but you still have to keep them above about %20 at a minimum. Always read the literature for your particular battery to be safe - failure to know what you have and treat it properly will lead to early/sudden failures.

- R

Not below 50% unless you go AGM, some of those can safely discharge down to only 20%! Having owned a few of them, I wouldn't go back to lead-acid batteries for the many advantages of AGM.

Deep cycle batteries can go all the way down, correct?

suncity 1 wrote:
We have 2x 6 volt batteries run in series in our TT. We do about 50/50 dry camp vs hookup. We want to get the most live out of the batteries. Is it best to keep them fully charged or better to run them down prior to recharging?

Lead acid batteries should always be kept at full charge, and stored at full charge. They should preferably never be run down below 12.2 volts or 50%, which adversely affects how long they will stay serviceable.