Charging Gel Batteries

Discussion in 'Tech/Mech General' started by daveandsan, Feb 6, 2015.

  1. daveandsan

    daveandsan Funster

    Joined:
    Dec 10, 2013
    Messages:
    1,234
    Likes Received:
    1,771
    Location:
    South Staffs
    I want to charge 2 new gel batteries before I fit them to our Motorhome, my question is will it safe to use my old CTEK xs 3600 charger. It has 3 modes and the car mode is 14.4V/3.6A.
    Sorry if it seems a daft question but I have never charged gel batteries out of situ before and I know that the onboard charger is set for gels so I wondered what the difference was.
     
  2. Don Quixote

    Don Quixote Funster

    Joined:
    Jul 29, 2012
    Messages:
    2,497
    Likes Received:
    3,696
    Location:
    Lost in La Mancha, Spain
    • Like Like x 1
  3. Lenny HB

    Lenny HB Funster

    Joined:
    Oct 18, 2007
    Messages:
    5,212
    Likes Received:
    5,002
    Location:
    West Sussex
    It would be OK but it won't get a full charge into them as your CETEK uses the same setting for Wet & Gel batteries, normally with a Gel you charge them until the voltage reaches about 14.2-14.4 volts and then maintain that voltage for 8 hours before reducing to a maintenance charge of 13.6-13.8 volts, the CTEK will probably reduced the voltage to 13.6 after one hour.
     
    • Like Like x 1
  4. jollyrodger

    jollyrodger Funster Life Member

    Joined:
    Oct 1, 2012
    Messages:
    3,409
    Likes Received:
    6,673
    Location:
    Plymouth
    • Like Like x 1
  5. Don Quixote

    Don Quixote Funster

    Joined:
    Jul 29, 2012
    Messages:
    2,497
    Likes Received:
    3,696
    Location:
    Lost in La Mancha, Spain
    Even your onboard charger will NOT hold the charge at 14.4 volts after 1 hour no matter what state the batteries are in. The Ctek will do the same as the on board.
     
    • Like Like x 1
  6. DavidG58

    DavidG58 Funster

    Joined:
    Feb 24, 2013
    Messages:
    6,269
    Likes Received:
    12,091
    Location:
    Bolsover, Derbyshire
    Why you want / need to charge them before you fit?

    They should be supplied new pretty much fully charged

    I would fit them and let the MH charger sort them out after
     
    • Like Like x 1
  7. scotjimland

    scotjimland Funster Life Member

    Joined:
    Jul 25, 2007
    Messages:
    28,934
    Likes Received:
    25,574
    Location:
    .
    The Gels you have purchased should have been supplied fully charged, so no need to pre charge (unless you know differently) .. just install and let the van charger top up


    snap ..lol
     
    • Like Like x 1
  8. eddievanbitz

    eddievanbitz Trader - Funster

    Joined:
    Oct 4, 2007
    Messages:
    3,538
    Likes Received:
    10,996
    Location:
    Taunton Somerset
    It all goes out of the window of course when you start the engine and put them in parallel with a wet Lead acid engine battery and an alternator chucking out 14.8vdc lol

    So it doesn't really matter in the real world, it will all do what it can do.
     
    • Like Like x 3
  9. TheCaller

    TheCaller Funster

    Joined:
    Sep 23, 2013
    Messages:
    1,809
    Likes Received:
    2,140
    Location:
    Lincs
    Only the battery manufacturer can tell you the correct charging voltage for their particular battery, but 14.4V seems to be the generally accepted maximum for gel batteries.

    It looks as if CTEK have gone for a compromise with this particular charger. They claim the one 'Car' setting is suitable for all common types, including AGM & GEL. They've gone for the upper limit on gel & accepted that it's a bit low for open cell batteries & some AGMs.
     
    • Like Like x 1
  10. daveandsan

    daveandsan Funster

    Joined:
    Dec 10, 2013
    Messages:
    1,234
    Likes Received:
    1,771
    Location:
    South Staffs
    Thanks for that, will do as Jim and David said and just fit them. Just waiting for the leads now to link them together. (y)
     
    • Like Like x 1
  11. TheCaller

    TheCaller Funster

    Joined:
    Sep 23, 2013
    Messages:
    1,809
    Likes Received:
    2,140
    Location:
    Lincs
    True enough for a simple split-charge system, although given the minimal cable sizes often used by converters, the voltage drop will probably protect a gel battery positioned well back in the habitation area. :D

    Does that still apply where something like a Schaudt Electrobloc is fitted? I know they have a gel setting to limit the charging voltage from the mains charger. Does that apply to the feed from the alternator as well?

    I seem to remember reading that some of the Electrobloc units can manage the opposite trick - where the cable voltage drop is so severe that the available voltage fro the alternator is now too low, the Electrobloc regulates it back UP to the level required for the battery type selected.
     
  12. Lenny HB

    Lenny HB Funster

    Joined:
    Oct 18, 2007
    Messages:
    5,212
    Likes Received:
    5,002
    Location:
    West Sussex
    Yes it will, the OP has a Hobby so probably fitted with an Elecktroblock, if set to Gel it will charge until voltages reaches 14.3 volts then hold at 14.3 for 8 hours before reducing to 13.8, if set to wet cell it will only hold at 14.3 for one hour.
     
  13. Don Quixote

    Don Quixote Funster

    Joined:
    Jul 29, 2012
    Messages:
    2,497
    Likes Received:
    3,696
    Location:
    Lost in La Mancha, Spain
    I stand corrected.
     
    • Like Like x 1
  14. eddievanbitz

    eddievanbitz Trader - Funster

    Joined:
    Oct 4, 2007
    Messages:
    3,538
    Likes Received:
    10,996
    Location:
    Taunton Somerset
    The EB still simply parallels the batteries when the engine is rnning +15 is on the yellow wire.

    Inside the unit is a normal automotive relay, so callling it a split charge is a misnomer.

    In practice though as you say with the skinny cables most converters use and the distance involved you would be lucky to get 14.4 vdc at the leisure batteries irrespective of if they are Gel or Wet

    Hence the aftermarket sales of Battery to Battery systems, fromm the like of Sterling Power Products and CTek. In those systems the batteries are seperated and each given the appropiate charge, based on the batteries requirements.
     
  15. steevie

    steevie Funster

    Joined:
    Apr 29, 2012
    Messages:
    295
    Likes Received:
    269
    Location:
    Holmfirth
    a few years back, I had gel batteries on my scooter, and they were flat, so as I was going into town[while on holiday] I attached them to my vehicle with jump leads. They were in the back, so I didnt see what was happening. Two miles there and back, and the gel batteries had gone from square to nearly round, and spewed gel out on the floor. I found out the hard way that you must have an intelligent charger for them, and never charge at more than 4 amps. Lead acid for me from now on.
     
Loading...

Share This Page