I was reading threads here and came across advice that its good to cycle a deep cycle battery once a month? My trailer has (2) 12v batteries and a solar panel that keeps them topped off, regardless of having my battery shut off switch turned off. Is that good or bad? Keep meaning to buy a disconnect for that positive solar wire to make it easy.Worried this might become super long and confusing. Let me lay out the situation with numbers. 1. 99% of the time i use the the trailer its plugged into shore power. 2. The trailer has solar panels and there is no disconnect between the solar and batteries. 3. I go out of town for weeks and unplug the trailer and also sometimes the solar charging wire. 4. (here comes the root of the question) I installed a fan that pulls 1amp. I want this fan to turn off and on several times a day using a 12v digital timer while im gone. So that leads to these questions:1. Should i power the 1amp fan from the main batteries and let the solar keep them charged? Then do a real cycle on the batts once a month or whatever is recommended?2. Since the trailer is 99% shore power should i pull the batteries out and put them in the cooler garage? Power the 1amp fan from a small independent solar panel? (will actually be set to 0.25amps so a small 10w panel should power it i hope. no digital timer the sunrise and sunset will be the timer)

There's no reason to cycle your batteries every month. It might be good to equalize them from time to time but the motion of an RV typically keeps the electrolyte stirred up. Equalizing isn't as big a deal with an RV as it is with a home or cabin battery bank that just sits there in the basement.Keep in mind that you MUST have batteries installed in your trailer to legally pull it down the road. They power the brakes in the event of a breakaway. If you have no batteries your disconnected trailer has no brakes and becomes a dangerous missile.If you have a good solar charge controller that is properly set up for your batteries there's no need to ever unhook it.

There is no benefit to discharging and charging a battery.No need to add complexity, leave the solar and fan connected and let the solar controller do its job.

Could have sworn I was reading a thread where several different people were saying to cycle batteries once a month.Summertime desert temps and using shore power. Pulling out the batts is a waste of time? The garage stays much cooler.

Ni-cad batteries need to be cycled now and then. But flooded lead-acid don't.

wopachop wrote:Could have sworn I was reading a thread where several different people were saying to cycle batteries once a month.Summertime desert temps and using shore power. Pulling out the batts is a waste of time? The garage stays much cooler.Flooded cells can get stratified if sitting on steady float for months between use. Some converters give a boost charge daily or weekly to prevent this. Solar would be in boost mode daily so no issue.Let the fan run and the solar charge every day. This is plenty of cycling to keep the battery in good shape. The fan would be best connected to the solar controller load controlled output in this case as it would cut off fan operation if the battery dropped below the specified voltage.Most solar controllers need to be connected to the battery when operating. Do not disconnect the controller from the battery without first disconnecting the solar panels from the controller.

Pull batts in the summer?--1a draw good for batts w/ solar?

time2roll
Nomad
Jun 29, 2018
wopachop wrote:
Could have sworn I was reading a thread where several different people were saying to cycle batteries once a month.

Summertime desert temps and using shore power. Pulling out the batts is a waste of time? The garage stays much cooler.
Flooded cells can get stratified if sitting on steady float for months between use. Some converters give a boost charge daily or weekly to prevent this. Solar would be in boost mode daily so no issue.

Let the fan run and the solar charge every day. This is plenty of cycling to keep the battery in good shape. The fan would be best connected to the solar controller load controlled output in this case as it would cut off fan operation if the battery dropped below the specified voltage.

Most solar controllers need to be connected to the battery when operating. Do not disconnect the controller from the battery without first disconnecting the solar panels from the controller.
mbopp
Explorer
Jun 29, 2018
Ni-cad batteries need to be cycled now and then. But flooded lead-acid don't.
wopachop
Explorer
Jun 29, 2018
Could have sworn I was reading a thread where several different people were saying to cycle batteries once a month.

Summertime desert temps and using shore power. Pulling out the batts is a waste of time? The garage stays much cooler.
beemerphile1
Explorer
Jun 29, 2018
There is no benefit to discharging and charging a battery.

No need to add complexity, leave the solar and fan connected and let the solar controller do its job.
KD4UPL
Explorer
Jun 29, 2018
There's no reason to cycle your batteries every month. It might be good to equalize them from time to time but the motion of an RV typically keeps the electrolyte stirred up. Equalizing isn't as big a deal with an RV as it is with a home or cabin battery bank that just sits there in the basement.
Keep in mind that you MUST have batteries installed in your trailer to legally pull it down the road. They power the brakes in the event of a breakaway. If you have no batteries your disconnected trailer has no brakes and becomes a dangerous missile.
If you have a good solar charge controller that is properly set up for your batteries there's no need to ever unhook it.

Forum Discussion

Pull batts in the summer?--1a draw good for batts w/ solar?

About Technical Issues

Related Content

Solar

TT batts

Solar panel

Solar Install

"Newer" Ford trucks don't charge house batt's?