Battery Shut off and Storage Question.

[Aluminum_Siding]

Hi everyone.

I store my trailer in the drive way. Therefor I can leave it hooked up to shore power 24/7. I have two 6v in series. I just got them yesterday and want to make the most of them.

Should I simply leave the trailer plugged in 24/7 keeping the batteries topped off. This will keep all the 12v stuff on when not needed such as circuit boards gas detector blue light on the radio etc.. It will also keep my trailers charger/converter thing running as well. Is there any downfall or undue wear here?

The other thought is to disconnect the trailer from shore power and shut the batteries off. Once a week or so plug in the trailer and turn the batteries on for a day to top off the batteries from their normal battery discharging that happens even when they are not in use.

What ya all think?

[Sam_Spade]

Nvr2loud wrote:

Splitting hairs.

SIGH.

It is not "splitting hairs".
The difference is important.
And I doubt that you have surveyed the entire market of all possible small chargers to be able to make that statement.

Harbor Freight was mentioned in one post.
One of their inexpensive small chargers claims to be automatic and the other one doesn't. Knowing which one to get is important.
(But I'm not sure I'd trust even their "smart" one.)

[Nvr2loud]

Sam Spade wrote:

Nvr2loud wrote:

My tenders are all smart chargers (unlike the charger built into the TT)

So the point IS that you should not refer to them as "trickle chargers", which is a cheap, dumb device.

Splitting hairs. A smart charger / battery tender is simply a trickle charger that shuts off until a voltage drop is detected. Almost all trickle chargers on the market now have that circuitry anyway.

[Sam_Spade]

Nvr2loud wrote:

My tenders are all smart chargers (unlike the charger built into the TT)

So the point IS that you should not refer to them as "trickle chargers", which is a cheap, dumb device.

[Nvr2loud]

Sam Spade wrote:

CavemanCharlie wrote:
And, we have many battery's in our farm equipment that set all winter long with no charge too. No problems with any of them.

It might be best (technically) to charge them up once and awhile in the winter but, it's not possible, and they seem to hold up just fine without.

I don't understand your use of the "technically" qualifier.
You are getting away with it but that doesn't make it right.

It depends on: How long "all winter" actually is and what type of batteries they are.

Also a starting battery can take slight mis-treatment for a longer time before it becomes noticeable (fails completely). A deep cycle RV battery will likely show a loss of capacity a lot sooner.

Agreed, I have trucks that sit all winter sometimes without ever starting. Those batteries sit just fine without a trickle charge and have no issues. My deep cycle batteries all come inside for the winter where I can easily maintain them rather then run tons and tons of electrical cords to all the storage tents throughout the yard.

[Nvr2loud]

Sam Spade wrote:

Nvr2loud wrote:
It keeps a trickle charge on the battery.

Since adopting this approach, I've kept the same battery useful for three seasons now!

We have long winters here, so the battery is out of the trailer for the entire winter and kept inside my basement.

I don't need or want to trickle charge an unused battery for 7 months.

A couple of points need to be made here:
An actual "trickle charger" is NOT GOOD to use unattended for more than 24 hours or so. If you really mean a low capacity tender type automatic charger than that's good; if you really have a trickle charger, you need to throw it away and get an automatic one.

If you have conventional wet cell batteries, you really DO need to have them on float charge or a manual shot of charge once a month.
Letting them sit for 7 months, the self-discharge will take them lower than they should be for longest life.

And lastly, if you have a way to charge the batteries while in the unit, there is no reason to remove them to protect them from the cold. They like the cold and won't freeze down to about -70F if fully charged.

It is an automatic trickle charger, designed to leave on batteries permanently. I get what you're saying, my primary charger 2amp / 15amp / 100amp with 6 or 12 volt switch does not trickle properly to maintain. When set on 2 amp, it charges continuously and can boil over the batteries if left for a long time. My tenders are all smart chargers (unlike the charger built into the TT)

Would need to run several hundred feet of extension cord to the trailer over the winter, or just remove the battery and put inside the house.

I have a bank of batteries in the basement all winter, all on battery tenders. Two boats, three ATV's, riding lawnmower, and TT batteries all come inside for the unused months.

[Sam_Spade]

CavemanCharlie wrote:
Is it possible that we are over thinking this a little bit?

Very perceptive of you.
Keep up the good work. :B

[Sam_Spade]

CavemanCharlie wrote:
And, we have many battery's in our farm equipment that set all winter long with no charge too. No problems with any of them.

It might be best (technically) to charge them up once and awhile in the winter but, it's not possible, and they seem to hold up just fine without.

I don't understand your use of the "technically" qualifier.
You are getting away with it but that doesn't make it right.

It depends on: How long "all winter" actually is and what type of batteries they are.

Also a starting battery can take slight mis-treatment for a longer time before it becomes noticeable (fails completely). A deep cycle RV battery will likely show a loss of capacity a lot sooner.

[CavemanCharlie]

Is it possible that we are over thinking this a little bit? Many of the more wealthy members here spend over 10 thousand , or at least thousands, of dollars on a TT. Then hurt themselves lifting a heavy battery out of it and carrying it down the basement to make it last 6 years instead of 5. Many of these TT only have one deep cycle battery.

That battery costs 100 dollars.

5 years is 60 months. Divided by 100 dollars is 1.7 dollars a month. 6 years is 84 months. Divided by 100 dollars is 1.2 dollars a month.


Of course I worded all of that wrong. lol I hope you understand what I'm trying to say even if I made it confusing.

[CavemanCharlie]

Sam Spade wrote:

Nvr2loud wrote:
It keeps a trickle charge on the battery.

Since adopting this approach, I've kept the same battery useful for three seasons now!

We have long winters here, so the battery is out of the trailer for the entire winter and kept inside my basement.

I don't need or want to trickle charge an unused battery for 7 months.

A couple of points need to be made here:
An actual "trickle charger" is NOT GOOD to use unattended for more than 24 hours or so. If you really mean a low capacity tender type automatic charger than that's good; if you really have a trickle charger, you need to throw it away and get an automatic one.

If you have conventional wet cell batteries, you really DO need to have them on float charge or a manual shot of charge once a month.
Letting them sit for 7 months, the self-discharge will take them lower than they should be for longest life.

And lastly, if you have a way to charge the batteries while in the unit, there is no reason to remove them to protect them from the cold. They like the cold and won't freeze down to about -70F if fully charged.

I agree with the first part about "trickle Chargers" being bad if left on all the time.

But, the battery in my boat sets all winter long with out a charge put to it. In the spring I charge it up before the first use, hook it up, and go. And, we have many battery's in our farm equipment that set all winter long with no charge too. No problems with any of them.

All of the above battery's are fully charged before winter and then the cables are unhooked from them.

It might be best (technically) to charge them up once and awhile in the winter but, it's not possible, and they seem to hold up just fine without.

[westend]

2012Coleman wrote:
I have also left my TT pluggedinto 30 amps at home, have forgotten about adding water to the battery, and "cooked" it. I plan on getting one of these Battery Tender jr.

from the link wrote:
The Battery Tender Junior has a mind all its own. This smart tender automatically switches from a peak voltage of 14.4 VDC to a floating voltage of 13.2 VDC. When the voltage drops below 12.6 VDC, the Battery Tender Junior resumes charging at 14.4 VDC. Your battery stays at a constant, operational voltage. A two color LED indicates the state of the charger.

$30 bucks, eh.
I may break out that perf board sooner than thought. 😉

[2012Coleman]

I have also left my TT pluggedinto 30 amps at home, have forgotten about adding water to the battery, and "cooked" it. I plan on getting one of these Battery Tender jr.

from the link wrote:
The Battery Tender Junior has a mind all its own. This smart tender automatically switches from a peak voltage of 14.4 VDC to a floating voltage of 13.2 VDC. When the voltage drops below 12.6 VDC, the Battery Tender Junior resumes charging at 14.4 VDC. Your battery stays at a constant, operational voltage. A two color LED indicates the state of the charger.

[westend]

An alternative: I have a box full of wall transformers that are cast-offs from broken devices or I've grabbed them when available. I chose a nominal 12V wall transformer. It's rating is 500ma. When unloaded, it's voltage is 16.2 DCV. I maintain a few auto batteries with this. If the battery has a voltage of 12.4 or 12.5, etc., I connect the wall transformer with a set of alligator clips. I monitor the battery until it reaches a voltage of 14 or so DCV. Disconnect, and the battery is charged. The length of charge procedure described varies by age, size of battery, and starting voltage. Typical duration is three or four days.

If I had more time on my hands, I'd break out a piece of perf board, interrupt the circuit with an appropriate IC, a few resistors and capacitor or two to make what essentially is a Battery Tender.

[Sam_Spade]

Nvr2loud wrote:
It keeps a trickle charge on the battery.

Since adopting this approach, I've kept the same battery useful for three seasons now!

We have long winters here, so the battery is out of the trailer for the entire winter and kept inside my basement.

I don't need or want to trickle charge an unused battery for 7 months.

A couple of points need to be made here:
An actual "trickle charger" is NOT GOOD to use unattended for more than 24 hours or so. If you really mean a low capacity tender type automatic charger than that's good; if you really have a trickle charger, you need to throw it away and get an automatic one.

If you have conventional wet cell batteries, you really DO need to have them on float charge or a manual shot of charge once a month.
Letting them sit for 7 months, the self-discharge will take them lower than they should be for longest life.

And lastly, if you have a way to charge the batteries while in the unit, there is no reason to remove them to protect them from the cold. They like the cold and won't freeze down to about -70F if fully charged.

[Nvr2loud]

My converter is not a good one, have destroyed a battery every season until I realized the problem. I now only use the built-in charger when on camping trips.

The remainder of the time, I pull the charger fuses out. I plug the trailer into shore power at home, then plug a trickle charger into one of my 120 volt outlets inside the trailer. The 12 volt side of the trickle charger then plugs into the 12 volt power plug beside the television. It keeps a trickle charge on the battery.

Since adopting this approach, I've kept the same battery useful for three seasons now!

We have long winters here, so the battery is out of the trailer for the entire winter and kept inside my basement. I cover the trailer just before Halloween (camp the weekend before Halloween every year) and then pull the cover off at the beginning of May. I don't need or want to trickle charge an unused battery for 7 months.