Did I kill my battery?

[aircommuter]

The hydrometer has become almost obsolete these days with so many battery types like gel cells, SVR, and of course they don’t test the cell interconnects either. I use a Mid- Tronics MDX-640 conductance tester.

[5picker]

Originally Posted by KeithInUpstateNY

If they disconnect only the negative lead and leave the positive lead connected to the battery have them cover the negative lead with some kind of insulating material, I use a finger I cut off a rubber glove. Otherwise if the negative lead makes contact with the frame it can short out.

Originally Posted by KeithInUpstateNY

It will definitely be pretty heavily drained from your description. Possibly to the point of damaging the battery, but there are too many factors to say yes or no. It would have been worse if you had done this in Texas or Arizona or Florida, the higher the ambient temperature the greater the self discharge rate, even if the battery is disconnected from the trailer.

The best thing to do would be to take it to an auto parts store and have them test it. They may also be able to put it through a "battery reconditioning" cycle, if you don't have a charger with this function.

The OEM charger in your trailer probably isn't going to cut it. If the charge is too low it won't even recognize that the battery is connected.

Good luck!

Originally Posted by Larry-NC

I do not understand the above statement.

• The "converter" will power the 12v loads in a trailer even if no battery is connected.
• The battery and the trailer are connected to the converter.
• Therefore, if the converter is powering the lights/fans/etc. in the trailer, it is also applying voltage to the battery. The only exception is when the 30/40 amp reverse polarity fuses have blown.

The converter voltage does vary a little, based on battery state of charge, but it will always apply a voltage in the 12-13 volt range.

Larry-NC,

I didn't understand either one of KeithInUpstateNY's statements.

I do not believe either to be true and would like some clarification from Keith why he believes so.

[debit]

I installed an RV disconnect switch at the positive side of the battery and a meter next to the switches to measure the batteries.
"batteries" as in plural, since I opted for the two 6 volt battery system.
You might upgrade to the 6 volt system; I am sure happy that I did. My batteries stay charged for a long time.

.................
Ram 2500 diesel / Surveyor 251rks

[aircommuter]

I think those statements 5picker mentioned are information from the misinformed.
Also using a hydrometer is not going to tell you a battery’s timed-discharge capacity. Not to mention you might get acid on your pants.

[rlh1957]

Even with the battery disconnect turned off it is possible for there to still be parasitic draw. My CO/LP Fire detectors still work and the little lights are always on unless battery is disconnected. That's why a trickle charge is best if you aren't connected to at least 15A shore power cord to keep battery up.
I charged battery is a little over 12V and 10V is considered dead my most. It may still operate an LED monitor light or CO/LP detector, but they will keep drawing down.
Auto-Zone and others can test your charged battery and let you know if listed amp hours are still actual or if battery is on the road to recycle.

[PenJoe]

First, I doubt you killed your battery. But, I will tell you this. There are two types of battery chargers-automatic and manual. Some have dual modes. An automatic battery charger will shut off/go to trickle charge when the battery is fully charged, a manual charger will not. Consequently, a manual charger can damage a battery if left on too long. An automatic battery charger requires some voltage that a totally discharged battery will not provide. Without testing the battery, an automatic charger may give the impression that the battery is not serviceable. A manual charger will start to charge a totally discharged battery provided the cells are good and the cells are covered. Once the battery is showing life, the automatic charger would normally charge the battery and then go to trickle charge. Having done my homework, I purchased a dual modes battery charger. It works.

When we leave home, we have several batteries that we charge before storing, do not use battery tenders, charge the batteries when we return. No problems. One of these batteries is a 7 yr. old marine starter battery. It is still serviceable. On our stored vehicle, we disconnect the battery and use a 2 amp trickle charger. When the battery is reconnected to the vehicle, no problems starting. We do store our batteries above freezing and periods of 6 months.

[Larry-NC]

Originally Posted by PenJoe

First, I doubt you killed your battery. But, I will tell you this. There are two types of battery chargers-automatic and manual. Some have dual modes. An automatic battery charger will shut off/go to trickle charge when the battery is fully charged, a manual charger will not. Consequently, a manual charger can damage a battery if left on too long. An automatic battery charger requires some voltage that a totally discharged battery will not provide. Without testing the battery, an automatic charger may give the impression that the battery is not serviceable. A manual charger will start to charge a totally discharged battery provided the cells are good and the cells are covered. Once the battery is showing life, the automatic charger would normally charge the battery and then go to trickle charge. Having done my homework, I purchased a dual modes battery charger. It works.

There's automatic and automatic.

The "simple" automatic ones apply a charging voltage and taper it down to a trickle as the battery charges. They often have a 6/12 switch, figuring you will be smart enough to set it to the appropriate value. This is what I would like to have.

The "smart" automatic ones magically sense the voltage and determine whether to charge using a 6 volt or 12 volt scheme. These (including mine) are useless. If there's no voltage, they simply won't provide them. The design engineers were too lazy to consider this case. All they would have to do is safely charge at constant current for 20 minutes and then sample the voltage. Repeat if necessary. This is what I have.

I got this charger to charge vehicles that had been sitting for a while. That's exactly what it won't do. They are hard to reach with another car and jumper cables, but that's what I will have to do--charge them enough that the "too smart for it's own good" charger will recognize them.

[tatosian24]

Tested the battery and it’s completely dead Going to slowly charge it. Battery disconnect install is in my future. The CO detector and some little lights in the USB ports pull from the battery...now I know...

[OntarioRVer]

Originally Posted by tatosian24

Bought a new TT and left it parked up at my parents on the 11th. Made sure everything was off that could be turned off...but I am worried that I am going to get up there this weekend and have a drained battery. Can a 75 amp hour marine battery last 2 weeks sitting or did I wreck it??

Hi Tatosian. Wow. You are getting a lot of technical advice on chargers, disconnect switch, inverters, etc. Which is good. But if you're like me and just want to keep it simple, here's what I do. Take the battery to a auto store that will test it for you. If the battery is no good, replace it with a good quality deep cycle. If the battery is still good, check fluid levels, charge it a bit and then reconnect. Drive the trailer and attach to shore power. Let it charge. While you're at the auto store, pick up two wing nuts that are designed for your battery posts. After you use the trailer, park it and disconnect both battery leads (more convenient with wing nuts). When you pick it up for your next trip, reconnect and go! If you store over the winter, remove battery and keep in your basement. Volt meter every month to confirm that you still have 12.6 volts across the posts. Your battery will last for years, with minimal maintenance. Good luck.

[babock]

If you have a decent converter like a Progressive Dynamics, you can have it charge your battery 24/7 if you want. Likely better than most chargers you would manually attach to the battery.

Put in a real disconnect switch. When I get a battery that has wing nuts, I throw them in the trash. You still need a tool to tighten wing nuts so they don't come loose so just get stainless nyloc nuts and use those.

Here is a good switch to get. Very high quality.

https://smile.amazon.com/Blue-Sea-Sy...gateway&sr=8-3

[campermatt]

Originally Posted by tatosian24

Tested the battery and it’s completely dead Going to slowly charge it. Battery disconnect install is in my future. The CO detector and some little lights in the USB ports pull from the battery...now I know...

If it's that dead, it will never recover fully. The battery they give you at AC Nelsen is pretty much garbage anyway.

I replaced mine right away with 2 of these 6V golf cart batteries from Batteries Plus. I used this battery cable from Amazon to connect them in series, and put them in this dual 6V battery box. It all fits nicely on the tongue of my 18MT. I don't worry about depleting the battery anymore. I do of course have to maintain the batteries by checking the water level, but that's no big deal.

[PenJoe]

Originally Posted by Larry-NC

There's automatic and automatic.

The "simple" automatic ones apply a charging voltage and taper it down to a trickle as the battery charges. They often have a 6/12 switch, figuring you will be smart enough to set it to the appropriate value. This is what I would like to have.

The "smart" automatic ones magically sense the voltage and determine whether to charge using a 6 volt or 12 volt scheme. These (including mine) are useless. If there's no voltage, they simply won't provide them. The design engineers were too lazy to consider this case. All they would have to do is safely charge at constant current for 20 minutes and then sample the voltage. Repeat if necessary. This is what I have.

I got this charger to charge vehicles that had been sitting for a while. That's exactly what it won't do. They are hard to reach with another car and jumper cables, but that's what I will have to do--charge them enough that the "too smart for it's own good" charger will recognize them.

I replaced a Schumacher Battery charger that died on me. It had to be 60 plus years old. They just don't make things to last!

Having done the research on charging batteries, I purchased another Schumacher Pro Series PS0122MA that is manual, automatic, 2 amp/10 amp 12 volt bench charger for deep cycle and automotive batteries. It was around $90, but it is now out-of-stock everywhere. Apparently, they stopped making it. I didn't need a 6-volt charge mode. Just out of curiosity I did a search for 6/12 volt charger with the same features and came up with this one at Walmart. Pricey, but it may be what you are looking for. It is a Schumacher Pro Series SP2100MA. It has manual and auto modes (MA).

https://www.walmart.com/ip/100-15-2-...BoCCKsQAvD_BwE

[babock]

If you are going with a stand alone portable charger, make sure you buy a true 3 stage charger. Ctek makes good ones.

[tatosian24]

Has anyone used a solar trickle charger? I was considering this one: Sunway Solar Car Battery Trickle Charger & Maintainer 12V Solar Panel Power Kit Portable Backup for Car Automotive RV Marine Boat Motorcycle Truck Trailer Tractor Powersports Snowmobile Farm Equipment https://www.amazon.com/dp/B01MYVUSRH..._eCbyDb90S56M1

[cousin01]

I agree with the comment about wing nuts. they have to be very tight to prevent heating and currnt drain and corrosion. So just stay with the nuts.

But read up on basic battery safety before you start using tools around a battery.

Make sure the rig is not connect to shore power.
Take off jewelry
disconnect negative first (don't freak out if you get a TINY spark when connecting or disconnecting, this is normal)
reconnect last.(again a small spark on initial contact is normal)
WEar eye protection
don't let the kids stand by and watch with the battery at eye level.

Be careful where your wrench is at at all times.

Use a proper socket or box wrench. Not a pair of pliers

these may sound overly paranoid, but if you don't do this stuff all the time a mistake can be DISASTROUS.

[Bridgo]

I had a switch installed with stops any power from being drained from battery and when I’m hooked to shore power I turn switch on to charge up battery and keep it charged. Minute I unplug from truck or shore I switch battery to off. That way microwave clock DVD player clock don’t drain down the battery.

[Flybob]

Originally Posted by tatosian24

Has anyone used a solar trickle charger? I was considering this one: Sunway Solar Car Battery Trickle Charger & Maintainer 12V Solar Panel Power Kit Portable Backup for Car Automotive RV Marine Boat Motorcycle Truck Trailer Tractor Powersports Snowmobile Farm Equipment https://www.amazon.com/dp/B01MYVUSRH..._eCbyDb90S56M1

Don't waste your money. Small units like these will not even keep up to normal losses. Generally 35- 40 W panels are a min for what you are trying to do.

[Pappygil]

Originally Posted by tatosian24

Bought a new TT and left it parked up at my parents on the 11th. Made sure everything was off that could be turned off...but I am worried that I am going to get up there this weekend and have a drained battery. Can a 75 amp hour marine battery last 2 weeks sitting or did I wreck it??

If you have a small meter set it to DC and check the voltage. If it is above 11.3 VDC your OEM system will work fine. Most OEM chargers provide 13.3 volts or above VDC to your battery and will charge it fine. If below 11.3 take it to a auto or battery shop to have checked. Batteries and bulbs is a good place. Good luck.

[jstich]

Rather the all the suggested "fooling around" check volts, check amps hydrometer,.................just plug the dang thing in and see if works, if it don't work buy a new battery, problem solved..

[BobnVic]

Originally Posted by tatosian24

Bought a new TT and left it parked up at my parents on the 11th. Made sure everything was off that could be turned off...but I am worried that I am going to get up there this weekend and have a drained battery. Can a 75 amp hour marine battery last 2 weeks sitting or did I wreck it??

The only thing that I can suggest is if your unit is equipped with an inverter, possibly if that is left on the battery could die in a short period of time. You learn from making mistakes, because I did it. Forgot the inverter was on. Drained both batteries.