Community Forums

GeeWillakers · 07-12-2016, 04:27 PM

I am about to add two 6v batteries to the two I already have. The originals are only a year old. They are wet (water) and I can add two new ones with oil and change the original to oil also to reduce evaporation by more than 90% according to Battery Direct.

Question is, will this affect the charging system and especially the battery equalizer mode?

ByeTheWay · 07-12-2016, 05:59 PM

An old rule of thumb is not to add new batteries to old batteries, but I have known others who have done it w/ out issue. Never heard of oil instead of water or is the oil on top of the water? I guess that has some merit, it will be interesting to see the comments.

jelag · 07-12-2016, 06:50 PM

I have never heard of oil in batteries... new to me... but have the following thoughts... if the batteries are charging and gassing off... this gas will pass thru and around any oil that might be on the surface... batteries gas off because they either have a bad cell or are in an overcharge condition...

If you look at any of the modern vehicles, with temperature control and the ability monitor battery static voltage (also know as "state of charge")... those vehicles batteries will/can go the life of the vehicle without adding water to the cells....

It would be great if the coach builders would put the circuitry into the vehicle to monitor battery static voltage, and battery temperature and than vary the charge rate based on the conditions that are required...

Your battery system is only as good as the weakest battery.... one battery with a bad cell... can/will prevent the rest of the batteries from going to 100% full charge...

ByeTheWay · 07-13-2016, 12:04 AM

15 years ago I bought 2 different styles of water saving caps only to find out the stock caps did a much better job. Then I got AGMs and the water issue went away

pcurt23 · 07-13-2016, 07:03 AM

Quote:

Originally Posted by iawia

I am about to add two 6v batteries to the two I already have. The originals are only a year old. They are wet (water) and I can add two new ones with oil and change the original to oil also to reduce evaporation by more than 90% according to Battery Direct.

Question is, will this affect the charging system and especially the battery equalizer mode?

One year old batteries should be no real issue. jelag is correct on the oil statement. Some people add mineral oil to the top of the batteries but you make it sound like you are going to run all oil in the battery. I would do a little more investigating before I did that. You could use Pro fill instead and that takes care of the off gassing.

Pro-Fill RV Edition Dual 6-Volt Battery Watering System - Flow-Rite Controls RV-2000 - Battery Accessories - Camping World

lonfu · 07-13-2016, 07:30 AM

Quote:

Originally Posted by iawia

I am about to add two 6v batteries to the two I already have. The originals are only a year old. They are wet (water) and I can add two new ones with oil and change the original to oil also to reduce evaporation by more than 90% according to Battery Direct.

Question is, will this affect the charging system and especially the battery equalizer mode?

yes, you can add battery's if the old ones are less than a year old. If you are losing water that fast, then I'd check your battery charger. Sounds like you are over charging them. Hook up a VOM and watch it go through the charge cycle. I wouldn't put anything in the batt but distilled water, the manufacturer will not honor there warranty. Check bat water every 6 months on all 6 volt systems. CLEAN YOUR TERMINALS!

One of the down falls of a 6 volt battery system.

12 volt batts seem to need checking about once per year. Most 6 volt batts last about 3 years then begin to slowly fail. If you don't replace them your charger will over charge them and they will usually fail at a faster rate and will cause problems with you control circuit boards. IE: frig

normal charge rate is 13.7 to 13.8 v across (2 in series) 6volt batts, any more than that and your batts will gas and loose water and fail early. If you have a smart charger and it fails to drop the voltage to the float voltage, then the batts are no good or the charger has failed.

Lastly, buy a "battery load tester" HF has them for about $30, volt meters do not tell you the ability of the battery to store a charge, only the voltage. Load meter will tell you how much current the batt can store. I myself prefer a 12v batt system because they cost less, but many moho manufacturers form their batt storage compartments to only fit 6 volt batts.

dennis45 · 07-13-2016, 08:38 AM

Adding mineral oil to wet cell batteries has been done since Thomas Edison.

For a 6V battery, add 4 oz per cell. 12V, add 2 oz per cell.

Do Not remove Electrolyte to add the oil. Wait until the level drops enough to add the oil and then top off with distilled water as required.

You should see a maximum of 13.7 to 13.8 VDC when plugged into shore power. Anything higher requires attention to the converter or, battery condition, which will also cause high charge rates.

I added mineral oil to my batteries when they were new about six years ago. I fully expect to get at least another two years or more service from them. My coach is plugged in 24/7 unless we are traveling.

My apologies for the upside down photo. Apple and this forum don't seem to get along.

GeeWillakers · 07-13-2016, 04:43 PM

Thanks for all the replies. I will probably go with two new regular 6v batteries and skip the new oil-based ones. I am not having any issues with the batteries, overcharging or otherwise. It is simply that the battery manufacturer said they have a new type that is filled completely with oil instead of water to reduce evaporation. I'm not sure if these will affect the charging of the batteries by my converter, which is designed not to overcharge the batteries, but which has an "equalizer mode". It is the latter capability I'm nervous about so I asked Triple E and so far haven't received a response. I will stay on the safe side and go with two new batteries that are the same as the ones that are one year old. Again, thanks for the input.

Gary RVRoamer · 07-14-2016, 09:50 AM

Quote:

It would be great if the coach builders would put the circuitry into the vehicle to monitor battery static voltage, and battery temperature and than vary the charge rate based on the conditions that are required...

All the better motorhome brands, and most all newer ones of any brand, do that. 3-stage chargers with temperature compensation are common these days, one of the benefits of low cost electronics.

Sehc · 07-14-2016, 12:14 PM

Oil filled batteries are used for deep under water applications such as submersible explorers. Sounds like a supplier is trying to sell you snake oil.

Dutch Star Don · 07-15-2016, 05:33 PM

If you have Interstates as your current batteries (a popular battery), Interstate sells rebuilt batteries that they often recommend as a good choice when adding addition batteries to existing used batteries. I did it a few years ago on my other coach and they worked well.