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Spatengal1's avatar
Spatengal1
Explorer
Jun 01, 2018

Deep cycle battery charger

Good Morning everyone
I need a good portable battery charger that will desulfonate, equalize and charge my 4 Trojan T145 house batteries. We have more than 1 rv so need it to be portable. I am sure there are many opinions on the best one. The batteries are series/parallel so I have 12v 520 amp hour output. I have emailed some mfg but have not really found one I liked. A couple of the reps said to buy 2 chargers but I would like to charge them all together so all equalized. Surely many rv's have a system like I have or better. They, like many, are stored for long periods of time so want the capability of getting the batteries back up to trip standards. I have automatic water system on them and a solar panel but still want to top them off before long road trip
Does anyone have any ideas on the best charger that "will do it all"
Thanks for the help
Pam

29 Replies

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  • BFL13's avatar
    BFL13
    Explorer II
    Jun 02, 2018
    Agree 100% with doing a (deeper is better) cycle and a "true full" recharge (including a shot of overcharge voltage as a "finish") at home before a trip. If not, the first cycle will get you to 50% sooner than desired. After that, you get better time before hitting 50% (not counting that you do 50-90 after that, so your first day you have an "extra" 10% )

    The batts need a cycle to get right up to speed after sitting there for a while, even if their SG looks good to go.
  • time2roll's avatar
    time2roll
    Nomad
    Jun 02, 2018
    OP is preparing for a trip not camping. OP said he has some solar so not sure why the big recharge is needed. If they were sitting a while maybe cycle them down 20% and recharge at 14.8 volts. Really should be close to full if the solar is working.
  • BFL13's avatar
    BFL13
    Explorer II
    Jun 02, 2018
    "It is all manual, so you do have to baby sit it "

    When you are camping using the gen to recharge, you need to be there to turn it all on and off. That is the extent of the baby-sitting with the gen and adjustable charger doing a 50-90.

    You need to know when you are at 90 so you can turn off everything and put it all away till next time (in a few days, perhaps) I use the Trimetric AH counter for that.

    The only thing you need to do other than that is set the voltage to say 14.8 ahead of time. After that you are free until you get to 90, which could be in two hours or so. Walk the dog. Read a book. Whatever, it is not a big deal that will ruin your whole camping trip.

    Here is the other end of the business, which you need to do anyway unless you have a built in Onan or whatever:

  • theoldwizard1's avatar
    theoldwizard1
    Explorer II
    Jun 02, 2018
    MEXICOWANDERER wrote:
    I am building one in my shop for another forum member. There never has been a "push a button and it does it all" battery charger so start thinking about compromises.

    Mex, you have to give him the background !

    First, if you read the recommendations that Trojan publishes about charging (bulk/float/equalize - 7.41/6.75/8.10) and then start looking a the specs that automatic ("push a button and it does it all") battery chargers do, you find there is a difference, maybe up to a 0.5V for the various stages of charging. Trojan will tell you that these differences will shorten the life of the battery. How much shorter is debatable, but it does seem to be true.

    Second, what Mex is saying, he feels he can do a better job of charging by using his "home brew" charger that he can adjust to very precise voltages. It is all manual, so you do have to baby sit it !
  • BFL13's avatar
    BFL13
    Explorer II
    Jun 01, 2018
    MEXICOWANDERER wrote:
    I am building one in my shop for another forum member. There never has been a "push a button and it does it all" battery charger so start thinking about compromises. BFL13 has tried many and has come up with the least offensive compromise.


    Mex means the one in the photo here. You can actually make any deck mount converter into a portable charger. Just cut off the end of a set of jumper cables (with big enough ampacity AWG) and stick that in converter's terminals. Big "parrot" clamps are ideal.

    This is a PowerMax 100 amp Adjustable model. You want the adjustable model, not the ordinary 3 or 4 stage, so you can choose the various voltages you need for the different charging jobs you mentioned in the OP.

  • Smitty77's avatar
    Smitty77
    Explorer
    Jun 01, 2018
    Many in the boating community, use these when they pull their batteries back to the house for deep conditioning/equalizing. Trojan needs GT 15.X volts, so getting a unit that has range to cover the voltage level Trojan recommends for your specific battery, is warranted:)!

    I've never owned one, but know two that have these, or in the family. Seem to be a decent product, at a relatively decent price:)!

    http://www.mastechpowersupply.com/volteq-power-supply-hy3020ex-30v-20a-over-voltage-over-protection-lithium-battery-charging.html

    Best of luck to you,
    Smitty
  • time2roll's avatar
    time2roll
    Nomad
    Jun 01, 2018
    Solar does all that in the best way if you have a good controller.
    Otherwise look at Battery Tender 20 amp, Xantrex TrueCharge or Victron.
  • pianotuna's avatar
    pianotuna
    Nomad III
    Jun 01, 2018
    Hi,

    If you store outside (in sun) and have a good solar controller with at least 60 watts of panel for every 100 amp-hours of battery storage, then there is no need for a charger.

    Spatengal@msn.com wrote:
    Good Morning everyone
    I need a good portable battery charger that will desulfonate, equalize and charge my 4 Trojan T145 house batteries. We have more than 1 rv so need it to be portable. I am sure there are many opinions on the best one. The batteries are series/parallel so I have 12v 520 amp hour output. I have emailed some mfg but have not really found one I liked. A couple of the reps said to buy 2 chargers but I would like to charge them all together so all equalized. Surely many rv's have a system like I have or better. They, like many, are stored for long periods of time so want the capability of getting the batteries back up to trip standards. I have automatic water system on them and a solar panel but still want to top them off before long road trip
    Does anyone have any ideas on the best charger that "will do it all"
    Thanks for the help
    Pam
  • MEXICOWANDERER's avatar
    MEXICOWANDERER
    Explorer
    Jun 01, 2018
    I am building one in my shop for another forum member. There never has been a "push a button and it does it all" battery charger so start thinking about compromises. BFL13 has tried many and has come up with the least offensive compromise.

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