BATTERY LIFESPAN survey...

16 days is tops for me... 21 foot travel trailer, summer time, solar panel and generator. Charge controller set at 15.0V, 120 watt panel that makes 6.6 amps, single 150 amp Trojan T1275 that had the rough life in a golf cart for a good 20 months before I got my hands on it. 150 amp hours rated, probably has 135-140 amp hours left in it at this stage in it's life. Daily usage at 30-45 amps consumed per day. Massaged heavily when I first got it with 3 or 4 16.0V @ 6amp/hr Equalize charge sessions with some 50% discharge cycles to really scrub the sulfur gently and slowly off the lead plates and get the SG where it needs to be. Ironically, SG read even higher after doing an Equalize cycle in July after getting back from June trip before back in storage... but I attribute that to 100F day heat, higher chemical reactivity helping get all the sulfur back into battery acid solution.

That was a big summer time trip to the Madison River, days were quite long in mid June. No shortage of solar harvest. Battery always had 12.45v most mornings, if I measured before the sun popped up.


Sept was 8 or 9 days, freak snow storm on Sept 11th, pipes froze, and fishing was nowhere near as good as in June. Ran the generator some with the S35-12 Mega Watt set at 15.0V, usually for 45 minutes to an hour... then solar panels took over.

Never any power posts since June of 2013. $30 to $45 a night chaps my hide, $200 for 2 weeks and having to drive to the Madison gives a fat fuel bill too and extra miles on the rig. Better to have a small travel trailer and camp on or very near the river, if one enjoys fly fishing.

Sorry I can't help you, but the battery was beat up fairly hard before being gifted to me... so I don't ever look the gift horse in the mouth. It may have it relatively easy now, life wise... but if I ever have to pay for a set, 6v GC-2's Trojans will be my selection, unless Li ION's drop to competitive pricing.

I am sure it saw 450 to 500 charge cycles in the golf car... H-1 is the date stamped on it, I received it Jan 2014. Not long in the tooth yet, but that's for my applications, probably not normal.

Will probably get over to Quartzsite, AZ for some winter camping, went with 150W panel that harvests 8.4 amps/hr for the shorter winter days and longer nights of Dec and January, will again set at 15.0V for the charge controller. Battery will get an Equalize charge session from small manual 6 amp Sears charger shortly before I leave on the trip, so she is in tip top shape at the start.

40 amps daily out of 135 to 140 amps, is not that deep into the charge cycle, battery seems to handle it in stride, daily solar charging helps out with that a lot, to keep the discharge cycles shallow.

My battery doesn't get much of anything, between trips, to recharge it, it sits in storage, disconnected. I will give a top charge or short equalize charge before starting on a trip, to give the battery the benefit of the doubt. It gets the same treatment when I get back home from a trip, top it off, brief EQ session, to desulfate the plates. Has not let me down yet camping.

MEXICOWANDERER wrote:
Near impossible to recollect the number of discharge cycles
So........


Anyone gone ONE HUNDRED EIGHTY BOONDOCKING DAYS on the same battery?

Doesn't sound like much unti you figure out this means twenty-six week long boondocking excursions or NINETY full weekends of boondocking.

With or without recharging via solar panels or generator/converter

But no power post 'tween charges
A tween charge means plugging ino a power post on day two
If you can with accuracy recollect actually receiving 180-days of charge discharges, for pofessional curiosity I am interested in learning.

HOW MANY DAYS BETWEEN RECHARGES?

FULL SIZE MOTORHOME/TRAILER?

CAMPER?

TYPE OF BATTERIES?

COMMENTS?

Not sure of how many dry camping days...

- recharged every day, about 50? dry camping days over 7.3 years of battery life.

- 2 x 6volts from Sam's Club - Energizer brand

- Trailer

- Batteries were just getting old, still working but lower capacity after 7+ years.

Edit, thought you wanted battery life...should have read the question closer. ;)

I don't do days between charges, either the sun shines and the solar carries us or Ill run the generator. We did have one day we didn't make it back to full but the solar was enough to keep us off of the generator until the sun came back out.

One thing is there is a difference between a shallow cycle and a true 50% cycle.

The longest I've done in one stretch is 29 days in February. 95 watt solar panel, 2 Interstate 6V 232 amp hr batteries. I did make a 74 mile drive towing the trailer during the time - maximum of 8 amp charge rate from the tow vehicle. Typical draw was 25 amp hours per day over the 29 days. Roof mounted panel, low winter sun. Most of the time was at the Imperial Dam BLM area in CA.

17' travel trailer.

Mex, not sure if this is what you want.

We have a seasonal off-grid site we park the 5er at and use as a second home/ cabin in effect from mid-April to end September each year since 2012. So that is three of those done at about 24 weeks each on the current sets of batteries. Also take 5er for a few long weekends in the woods in winter.

One pair of 6v Interstate GC2 XHD 232AH (new Feb 2011) still meets baseline SG and full capacity

One pair of 6v Exide GC135 at 226AH (new Nov 2011) still meets baseline SG and full capacity

One pair of T-1275 12v batts (new May 2011) previously in a golf car for two years has now done one full season 2014 and is still in the same shape as after I "recovered" them late 2013 when I got them.

I think I could do it all for the next few years with just the two T-1275s and not have the four 6s, but am not going to dump four good 6s.

We sit there on solar for the 24 week season and do fairly shallow cycles daily maybe 85-99% SOC except for the odd cloudy time when we get down to 50% before doing a generator/charger recharge. On winter weekends in the woods no solar a 50-90 every second day with all six batteries. Was 50-90 every day with just the four 6s so the two 12s added on make a big difference there.

With the solar shallow cycles it is no great strain on the batteries like doing 50-90s, so IMO the batts are not doing anything exceptional.

Something I didn't think of is when we use the big inverter, the solar helps the 8-D but it is still cycling numerous times a day.

This was fairly typical use on our sailboat:

Basically "wet camping"-- batteries charged by alternator 8 hours a day when in transit. Once in the Bahamas, at anchor/mooring. 2 4D Lifeline AGM's. largest draws were 12 VDC refrigeration unit, interior and anchor lights. Engine run 30 minutes AM and PM to recharge and make hot water (engine produced hot water). 120 amp alternator and Xantrex smart regulator. 30 minutes would just get into absorption phase with charge rate dropping to below 30 amps.

Yes, occasionally we had "marina days" to shop, do laundry, etc and were on shorepower overnight.

Batteries lasted 2 round trips (3 years) Texas to Bahamas and an additional 3 years. Just replaced this year with more Lifeline 4D's.

Discharge, recharge cycles, battery life ?
My AGMs are 3.5 years old, we got them in July 2011

Since Oct 2012 they have had one week of shore power Jan 2013
But they get solar and generator almost daily
But they also get a heavy work out every day, including running an electric blanket, all night every night, now that temps drop to the low 30s at night, frost every where this morning, this is in addition to the fridge, TV, laptop..etc...
Right now the solar cannot keep up with our daily use, but it helps

Hi Mex,

From March 2009 to June 2013 I had no generator. I used the RV 50 nights per year with about 50% of them with no shore power. Charging sources were solar (May 2009), alternator, and a PD 40 amp converter with wizard.

Solar did 100% of the storage charging. Blue Sky controller with a temperature sensor powered by 256 watts of Unisolar panels. Any equalization that happened was via the Blue Sky on a 30 day cycle. I do have a switch installed so I can "force" an equalization voltage.

Alternator did do lots of charging as my travel distances average 1000 miles per month, mostly at highway speeds. The fridge was operated on 120 volts while "on the road".

Shore power was used to cool the fridge before trips (6 hours), but of course the battery bank was always topped up from storage.

Power use was recklessly as at that time I had a 2500 watt MSW inverter that I used to power the "whole house" with the exception of the converter. I cooked with two hot plates. I would use 60 pounds of propane per year. Trips were up to six nights, with one longer trip per year. The RV was operated pretty much as if I had shore power 24/7.

Opportunity charging was done mostly with 15 amp shore power with the PD 40 amp. Space heating used up to 1500 watts while the charging was done.

The battery bank consists of 4 Walmart Marine batteries that were 5 years old in May of 2009, and 4 similar batteries that were new in May of 2010, one of which was used as a chassis battery. They are independently switched from all loads and charging sources. i.e. I can charge one bank while using the other. A second charging circuit from the alternator was added to allow this.

Additions and upgrades have been a Magnum 3000 watt hybrid inverter/charger(May 2014), and a Yamaha 3000 sIEB generator (June 2013). Remote start was added to the generator in March of 2014.

Until I got the Magnum inverter, I rarely used the "equalization" switch on the Blue Sky. Now I use it when the Magnum is in charging mode from the generator, as the Magnum charge voltage is enough to "fool" the Blue Sky into providing no charging.

The generator has been run less than 100 hours since it was purchased.

I'll replace the banks with AGM, when the time comes, unless cold weather LI batteries become available and affordable.

I have been full time since May 1, 2013. I do a lot of "urban docking", parking at Chain Stores, or on the streets.

In the last year I've had shore power for 4 months. About 50% of that shore power was 15 amp from private homes and Church parking lots. The RV was in storage for 2 months in 2014. The other 6 months I boondocked.

I've used 4 tanks of fuel in the generator in 2014, and used 56 pounds of propane. 50% of the generator time was to run the roof air and of course I opportunity charged the battery bank.

I can still operate the air conditioner from the battery bank for over an hour before low DC voltage shuts it down.

I'm currently in Florida and the RV is in storage in Saskatchewan.

Like many, I'm not sure what you're going for with this.

Small 5th Wheel, 2 7year old no-name GC's. I recently did a load test, and they seem to have about 75 to 80 of their rated capacity.

We are "on the road" 2 to 4 months every year, we prefer state/national parks, and dry camp at least 4 weeks or so a year. That would equate to about 200 days dry. I have a gen, and until a couple of years ago, that was our only source for recharge. We usually only needed to recharge once during the week, as we are very conservative. Cold weather and heater use sometimes did drain us down. Since adding 240 watts of solar we seldom need the gen; this year I only used it once.

Doug