Forum Discussion

Gundog's avatar
Gundog
Explorer II
Feb 17, 2019

New batteries I have some questions?

I plan to change out the house batteries in my 05 Expedition. The current batteries were boiled dry prior to my owning it.

I want to put on all new cables and a Flow-Rite watering system in. The cables on it now don't fit well and some have to be disconnected just to check the fluid level in the batteries. I plan to put on new cables cut to fit properly.

I have the tools and skills to build the cables but I am not sure what size cable they use I am guessing it looks like 2/0 welding cable.

I plan to buy the 6 volt Interstate batteries sold at Costco. I believe that is where the batteries that are in it now came from they would probably still be good if they would have had the fluid level kept full.

I am also thinking of putting in a separate charging system on the batteries when it is stored. I leave the MH plugged in my inverter charger has a button that turns off charging to the battery bank. My thought is to turn off the charging through the inverter and using a better battery charger that will not over charge the unit.

I am not really wanting to buy a new inverter since it works fine other than over charging. This auxiliary charger would only be used when the Mh is stored for long periods of time and not used when we are using the unit.
Class A
  • KD4UPL's avatar
    KD4UPL
    Explorer
    Feb 18, 2019
    If you have a fairly modern inverter/charger it is likely just as capable of properly charging your batteries as any other charger if it is programmed properly. The nice inverter/chargers like Xantrex, Magnum, Outback, etc. have many different voltage and current settings that can be custom programmed to the exact specs your battery needs. If someone did this wrong (like set the voltage too high) you would certainly boil the batteries. I can't imagine a new charger is needed, just proper programming. Do you have a battery temperature sensor? Is it installed correctly?
    2/0 cable doesn't sound like overkill to me at all. What is the wattage of your inverter? Assuming it might be 2,000 watts it could pull as much as 200 amps from your batteries under full load. I wouldn't go less than 2/0 if that's the case.
  • pianotuna's avatar
    pianotuna
    Nomad III
    Feb 18, 2019
    Hi,

    My battery filler system was made from rather friable plastic. It broke when it was being installed. I'd go to used telcom AGM jars. Mine are adequate to my requirements after 4 years of full time.

    Most smart chargers are notorious for not completely recharging the battery bank. That leads to sulphation. I'd go with the best recharging system possible.
  • Big_Katuna's avatar
    Big_Katuna
    Explorer II
    Feb 18, 2019
    It’s a good inverter. I believe it has a float phase. Switches over well; tv doesn’t flicker.
  • Gundog's avatar
    Gundog
    Explorer II
    Feb 18, 2019
    wa8yxm wrote:
    You said the batteries were boiled dry before you bought it.. What coverter does it have.. YOu may wish to do a converter upgrade.


    I was hoping to avoid that expense.
  • Big_Katuna's avatar
    Big_Katuna
    Explorer II
    Feb 18, 2019
    Hi Gundog. I have the same problem with my 05 38N. I too, have the Profill but I still forget to fill monthly. The separate charger may help. I’ve never gotten more than five years out of batteries.

    Which brings me to my next topic. My Maintenance free engine batteries are in year 8 and still spinning her just fine. My house batteries are five and are shot

    We rarely dry camp so I’m going to replace the four sixes with two big dual purpose maintenance free 12 volts. My wiring is worn out anyway.

    They should work fine for the led lights and flat screen tv the few times we do that.
  • wa8yxm's avatar
    wa8yxm
    Explorer III
    Feb 18, 2019
    You said the batteries were boiled dry before you bought it.. What coverter does it have.. YOu may wish to do a converter upgrade.
  • Sam_Spade's avatar
    Sam_Spade
    Explorer
    Feb 18, 2019
    I think that deep cycle AGMs are well worth the extra money.

    The "watering system" is just something else to worry about.

    That disconnect switch disconnects the batteries from everything.

    IF....you don't really need power during storage, there is no good reason to leave the RV system plugged in at all. An automatic tender type charger would work fine but I find that my rig will sit for 3-4 months and my AGMs are perfectly happy with no charging at all, IF they are fully charged going in.

    And finally, loose cable ends can often be fixed without putting on new cables. Sometimes just new bolts. Sometimes new ends.

    Good luck. Try not to make things more complicated than they ARE.
  • theoldwizard1's avatar
    theoldwizard1
    Explorer II
    Feb 18, 2019
    Gundog wrote:
    I have the tools and skills to build the cables but I am not sure what size cable they use I am guessing it looks like 2/0 welding cable.
    .
    .
    .
    I am also thinking of putting in a separate charging system on the batteries when it is stored. I leave the MH plugged in my inverter charger has a button that turns off charging to the battery bank. My thought is to turn off the charging through the inverter and using a better battery charger that will not over charge the unit.
    The size of the cable depends on the highest current draw and the distance. What does your inverter manufacturer recommend ? (2/0 sound like over kill.)

    How will the auxiliary charger be connected and how much current will it send to your battery bank ?

    It sounds like you will have at least 2 or 3 connections for +12V (inverter/charge, DC distribution panel, auxiliary charger). I might be better to install a shield positive bus through a 100A fuse to the positive terminal on the battery. Also a good place to installed a Master Cut Off Switch.
  • Trackrig's avatar
    Trackrig
    Explorer II
    Feb 18, 2019
    I have a 2005 Fleetwood Excursion 39S which is close to your DP. You probably also have Xantrax 458 charger. I live in Alaska, but the DP is stored in AZ under covered storage. I find far more battery water is used / evaporated during storage when it's not plugged in due to the heat. I don't know if you have a heat problem at your location or if you're on the wet side of WA.

    When I pick up the DP next week, one of the first things I always do is check the battery water level even though I topped them off when I put it in storage.

    If you wanted more amp hours, you could go to Trojan 125 batteries which are taller like I did because we dry camp some. I'm not sure the Trojans are worth the extra money. The Costco batteries are a good battery for the money. They won't last as long as the Trojans, but then they don't cost near as much either. You can buy at least three sets of Costco batteries for what two sets of Trojan 100s go for.

    Anyway, after you put new batteries in, continue to monitor the battery water level on the new charger to see how the water usage compares to the Xantrax. If the water usage is less, then it was probably the charger. If it's about the same, then a lot of it was probably evaporation like mine.

    Bill
  • MountainAir05's avatar
    MountainAir05
    Explorer II
    Feb 17, 2019
    We use a Smart Charger to do it. It is made by Ctek

    https://smartercharger.com/ It has been in use for the past 7 years with our batteries and no issues. It is not made for batteries that need a heavy charge. So have to be charged up and will maintain them very well.

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