Deep cycle battery care

[Clyde9]

From: brians69d24  (Original Message)   
Sent: 8/26/2007 4:39 PM

My house battery is alway on my guest 3 stage charger. Question. Should I periodically shut down my converter and charger and draw the deep cycle battery down?

brian



From: Cooneytoones   
Sent: 8/27/2007 8:41 PM

Great Question Brian,

I've never heard or read about having to do that. I would think as long as a battery is maintained at near 100% state, as long as it is not overcharging or boiling away, freezing ect.

On the other hand, it won't hurt it to draw it down once in awhile to make sure your charging capablities are working properly, timing of usage before it dies and how long to re-charge back to 100% . So when your boondocking, you won't have to walk out of Dodge, or be in the dark longer than need be.

Timmy.



From: tiinytina   
Sent: 9/3/2007 6:20 PM

I've heard 2 different stories on batteries. One is that "rechargeables" should always be drawn down before recharging. The other is to keep them charged up.  If one applies Physics... it shouldn't matter because the charge between positive and negative work to keep themselves in balance....

I can say for our coach batts.. 2 deep cycle marine type. I check them a few days before we go out. Our coach batts are at least 5 yrs old  but I'm fairly sure the PO bought them new but let them run out and left them dead until he needed them. Now we recharge them and my panel will read full but a day later parked with the only draw a rechargeable flashlight we leave plugged in, and the rig on shore power, the batts were dead. And yes I guess I'm a bad RV owner.. as I leave the batts in all year so they do freeze and thaw etc....  So next year I think new batts are in order and since I will be shelling out $$ I will probably drag them in and out with the season... but in all due respect we do go over in the winter and run her and work in her etc to run the fridge and furnace etc...

I have a deep cycle marine battery in my house on constant trickle... it runs my sump pumps when the power fails... and to date... it is over 10 yrs old and runs those pumps when the power fails.... I'm thinking that given this (which may or may not be a fluke) , I may install a permanent trickle on rig that will charge whenever we are on shore power....

tina



From: OldEdBrady
Sent: 9/3/2007 8:56 PM

I've poste dthis in other discussions, but...

Bak when I had the Whiny Beggar, I went to Harbor Freight and bought one of those small solar panels.  I think I go it on sale for $10, with a regular price of either $15 or $20.

Anyway, It's one of those you plug into a cigarette lighter.  Anyway, I didn't plug it in.  I hard wired it with a cutoff switch.

When the Beggar was in the driveway, the switch was on.  When we were underway, the switch was off.

Never had a problem with the rig battery, nor the deep cycle.
   


From: DanD2soon   
Sent: 9/3/2007 9:17 PM

I'm a little concerned we're talking apples & oranges here.

Tina,  "Rechargeables"  as in Ni-Cad batteries used in lots of electronic appliances, portable tools and some cell phones do well being drawn way down before they're recharged - in fact charging them too often or too soon can cause a problem known as memory where the battery "thinks" its dead after as little as 10% of its charge is used and it just refuses to provide any more output.

Lead Acid storage batteries - the kind most often used by us in our RV's are a whole different animal, sorry, fruit.  Even among these lead acid batteries there are basically three types - I like to call those Starting, Deep Cycle, and Fairy Tale (so called deep cycle marine.)  Your Chassis battery, the one that starts your engine, powers your running lights and is recharged by your alternator, needs to be a Starting battery (usually rated in Cold Cranking Amps/CCA)  Your House battery, the one(s) that runs your fresh water pump, 12V reading lights, 12V vent fans, inverters, etc. needs to be a Deep Cycle. (Almost always rated in Amp Hours/AH)  The Fairy Tale Deep Cycle Marine is always a compromise between the other two and seldom does a good job performing either of their tasks and often suffers from short life in both applications.  One of the best explanations about RV use batteries can be found at this link:   The 12volt Side of Life (Part 1)   Its well written and an easy read, well worth the time.

Brian,  If your Deep Cycle is really a deep cycle, drawing it down to 40-50% of full charge won't hurt it at all.  On the other hand you should do everything you can to keep from drawing your Starting battery down any more than necessary - fully discharging a starting battery, even a few times can kill it.



From: tiinytina   
Sent: 9/4/2007 5:36 PM

Dan,
  thanks for the site info.... I didn't mean RV batts are "rechargable" like NiCads... but by trickle charging etc deep cycles.  Ours at this point are drawing down quickly from full to nill as in under 24 hrs. Our allegro has a main coach battery cut off switch and this is off when parked. We have to switch it on when plugged in for everything to work and while driving so that the fridge stays lit etc.... I have non refillable/sealed deep cycles but there is no date stamped on or punched out on them to tell when they were installed. I'm thinking our 4-8 yr life is up. Fortunately we don't boondock at all and have a genny (though the coach batts have to start it up!)...

Tina



From: bluebird5750   
Sent: 9/4/2007 10:22 PM

While talking battery's, stay away from wally world battery's. There is a wallmart very near my house, so I bought several battery's from them. Every one of them was bad within 12 to 14 months. A couple of them were replace with in the first year. The ones in spare time lasted 23 months, yes I did get free replacements. But still a head ache. 

Chuck



From: DanD2soon   
Sent: 9/5/2007 7:30 AM

I think you're right Tina.  If yours are going from "full to nill" in 24 hours with the cut off switch off, they've already departed for the great beyond.  And, all things considered, sounds like they served pretty well.

Near the bottom of  Mark Nemeth's 12 Volt Side of Life article (Link above) he has a few paragraphs about Winter Storage.  Among other things, he talks about various ways of keeping the batteries charged and precautions for each - good info.  He also suggests ways to find and stop "phantom loads" that can drain our batteries.  These have given me fits over the years - no problem for those of you who have cut off switches - except that having the switch Off often prevents your charging system from keeping the charge up.  He also makes a nifty suggestion involving a plug in timer to prevent overcharging and cautions everyone to check their battery voltage and electrolyte levels at least monthly.

I don't think that last one can be stressed enough!  Neglect kills way more batteries than Abuse.



From: DanD2soon   
Sent: 9/5/2007 10:51 AM

CW Administrators - O.K. - I did it again! - twice - So flog me.
I'll add this to both threads as penance for my sins - It's just SO hard not to jump in when a fellow member is having a problem & you think you can help.  Never mind that you're "re-inventing the wheel."  Like the Ole Cajun said - "When you're rear end deep in alligators, it's hard to concentrate on draining the swamp!"

A quick message search using "batter" (to find battery or batteries) & "charg" (to find charge or charging) found these results and many others...

Helpful Links -
From LJ-TJ:  in CW Message:  Battery Information  ;   http://www.surepower.com/pdf/ebr_int.pdf
From BoatNut:  in CW Message:  Battery charging advice needed ; http://bart.ccis.com/home/mnemeth/12volt/12volt.htm
Also in that same message from Cooneytunes: winter battery advice http://koa.com/updates/2006october/RV101.htm

CW Message: Charging deep cycle batteries
CW Message: All Batteries going dead
CW Message: Batteries won't charge with engine running
CW Message: Batteries: How do I charge both while driving?
CW Message: Battery Charger - electronic state-of-the-art
CW Message: Charging while hooked to shore power? - Winter Storage

OH Great Ones!  I Pray Thee a Thousand Pardons...



From: AllanCZ   
Sent: 9/6/2007 6:27 P

<quote>While talking battery's, stay away from wally world battery's. There is a wallmart very near my house, so I bought several battery's from them. Every one of them was bad within 12 to 14 months. A couple of them were replace with in the first year. The ones in spare time lasted 23 months, yes I did get free replacements. But still a head ache.

Chuck </quote>

Opposite experience here. I've always had good luck with Wal-Mart batteries. 3 cars, 1 truck and the bus with both truck/house batteries.



From: tiinytina   
Sent: 9/16/2007 4:19 PM

ok that all said... looks like I will be replacing my 2coach deep cycle marine batteries next season... Given we are keeping Gone for as long as she will hold up... what brand of battery or kind of battery would be the best to invest in?  I can't tell you off the top of my head what is in there now. I know they were purchased by the PO and are 5-6 yrs old.  I do plan on installing a solar trickle charger at some point, just have to figure how to run the wires.... Has anyone simply mounted the panel to the battery door? Our rig when parked gets sun on that side from 9am to 1 or so.... hmmmmm.

thanks
Tina
(aka Lil' GTO)



From: OldEdBrady
Sent: 9/16/2007 6:17 PM

(MSN is acting up again!  Took 4 tries to get this far!)

Anyway.

Tina, the panel I referred to in a prior message can be mounted anywhere.  There are two screw slots in the back that they can be hung on.  Or, as an alternative, two small holes could be drilled at the edge of the panel and screws/bolts put through there to mount permanently.

As for polarity, use a meter.  If you get one of those like the one I mentioned that has the cigarette lighter connector, the center contact is the positive side.  Cut the wire away from the connector, and use the meter to see which wire is "hot"  by connecting one meter lead to the center contact, and then checking each wire separately with the other lead to find the correct one for positive.  Those wires were coded (one solid black and one with a white stripe).

With mine, I just mounted it in the front window.  I didn't need sunshine to make it work--just light.



From: tiinytina   
Sent: 9/17/2007 6:41 AM

My coach batteries are 14' away from the dash and the cigarette lighter only goes to the engine battery... so I'll probably just mount the solar charger on the battery box cover vertically. Should be able to secure it enough so it A) won't get stolen and B) won't blow off hauling down the road....
Tina



From: tiinytina   
Sent: 10/4/2007 6:02 PM

ok... I am blond... so it took a while... I double checked the coach batts... and they are refillable. So 1 qt of distilled water later... the batts went from nill to full! yipee.  Genny cranked up after a minute of trying.... and now need to tighten the wing nuts down with pliers instead of my glass sliced fingers...
tina



From: tiinytina   
Sent: 10/8/2007 5:07 PM

Ok batts cranked my genny no problemo for the trip out to Da Pond. Coach batts were turned off for the duration of the weekend since we had 20 amp shore line. Went to crank the genny for the return trip and... click click click... zero charge. One connection on one battery was a bit loose but tightening it did nothing. 2 hrs on a trickle and genny started and guage is reading 3/4....  so leaving it be, stored in off position.... We will be taking her out weekend after next hopefully for the last trip of the season... so we'll see.... i've put new batteries on the wish list for next year. Her reregistration just came in today $190....

tina