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Start out on the right foot with your battery!

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  • Start out on the right foot with your battery!

    This is primarily intended for the newcomer to solar, especially those experimenting with 12v systems.

    Batteries of course are a huge part of the plan, and while reading the threads and subforums yields great advice, I KNOW that many of you will attempt to put a battery into service that may be old or inappropriate for the job.

    Whether you just slap something in to see if it sticks, or have done all your homework to "right size" it for your system, the idea is to be SURE you are starting out on the right track - that is making your battery as serviceable as possible, which can mean a little bit more than just fully charging it.

    I have seen quite a few projects that go to great lengths to get things exactly right, yet the battery they use is the culprit for poor performance. The biggest problem here is that unless you know how to ascertain your battery health, you may be led to making false conclusions about your other gear!

    Without a lot of experience, or test gear to prove that what you are reading is true, I can make a suggestion:

    Start your project by using a Tecmate-Optimate 6 ac charger on your battery first, AND being sure to let it finish the job - which is at least 12 hours or more after it finishes the job, since it is still testing / charging before it reaches a conclusion, and displays the battery health conclusion to you.

    Ok Mr. Salesman, why is that? This is the internet, so you should trust me.

    Read their manual online if you want to get into that. Essentially many other cheap automotive chargers are either too agressive, too weak, or too cheap to do the job *right*, despite a lot of sales hype. And doing it right means that a battery geek like me will watch what they do with their own voltmeters / ammeters inline to actually PROVE what they claim is true.

    The best part is that it can appeal to both the battery geek and the neophyte. I watch and monitor what it does for the entire process. Normal people can simply attach leads to the terminals, plug in the ac, and walk away.

    It is more than just a blink-led toy for geeks. It is a real TOOL. I consider it just as important as the oft-recommended Kill-A-Watt meter. The best thing about this tool is that the neophyte can simply clamp up and walk away (although I recommend NEVER leaving a battery on charge unattended!)

    While I would love everyone to read the threads, get the appropriate NEW battery for the job, I know that in the real world, many will put a used one in place instead. At the very least, let a Tecmate-Optimate 6 (or 5 if you are really on a budget), vet the battery performance to see if you are going to just stumble out of the gate, or start on the right foot.

  • #2
    Can this Tecmate-Optimate 6 ac charger de-sulfate 400 amps deep cycle batteries like Roll 4000 series battery. It is only 5 amps output, but the website say it can de-sulfate deep cycle batteries, I wonder if you have any experience on the large batteries.

    Thank you.

    Comment


    • #3
      Good question - The 6 only supports up to 230ah, and the 5 model supports 120ah and progressively further down the line ...

      However, I might chance it - if only to burp that battery up to a state that it will start to accept a charge from another source, not as a recommended normal charger for your battery which is twice the rating in ah. Part of their routine is measuring not only voltage, but internal resistance against ideal charge slopes in the firmware - so for a battery double their supported range I'm not sure if it would get confused or not.

      I'd contact them with this question - would it at least desulfate a battery twice the supported ah capacity to the point of letting another higher amperage charger finish the job? They are also under the Accumate name in the UK.

      When it detects no external wiring, the desulfation pulses (PRIOR to bulk!) can get up to 22v when it detects no additional wiring hanging off the battery for it to works it's best. But it is smart and varies. Very interesting to watch, BUT I have only done the revival to friends Optimas and Odysseys. Of course revival from extended deep discharge does not mean damage hasn't already been done, and at least these guys are honest enough to tell you so right from the start.

      You might be able to "reset" it for an additional go-around if it times out on you, but they also wisely warn that not every bad can be desulphated - at least to the point of being usable to sustain a load.

      That being said, my success rate has been very good with other agm's, including those that were - yes - out of balance! With no access to the cells, their version of absorb is an oscillating ramp up and down from about 14.0 to 14.3v - all the time watching internal resistance, voltage, absorb current and the like. I guess that's how they kind of get away with it being general purpose, although I *still* would be cautious about gels, even if oscillating the absorb.

      Basically I don't have the time or patience anymore to sit on the bench with a variable-bench supply and tweak the voltage and current in minute-increments all day long for chores like this. But that is a great way to do it too.

      Comment


      • #4
        Don't get suckered into miracle cures!

        Now that we've brought up desulphation - nothing draws the quacks out of the woodwork like this topic.

        I use the Optimate 6 as a tool - primarily for initial commissioning of new batteries, preventative maintenance, and best of all the extensive testing.

        The very best thing you can do is start with a NEW battery, and TREAT IT RIGHT. That means knowing about what your DOD values are. These are covered in other threads.

        Some guys like to buy these chargers or desulphators, and try to bring back the dead. In many cases, if you get to if soon enough, it works, although that abuse will have a small bit of a toll. On the other hand, don't get disappointed when it won't bring back some POS little agm battery pulled from a UPS that has been sitting totally discharged for 4 years. For kicks I did this, and the Optimate got one foot out of the grave, but the only load it would sustain was a 9v radio. Gotta' get real. The Optimate works well, but there IS a point of no return.

        Other common quacks are using Epsom salts, and my favorite - guys popping the caps off of sealed agm's, and putting distilled water into them because they see that they are "dry" inside. HELLO! That is how agm's are built, and by cracking the caps and adding water, you just made a very poorly performing flooded battery out of it. Consequently, the charge rate is waaay too high now, and the now opened caps just overflow. Avoid such "discoveries" that your poor little agm just needed some watering. These guys just don't know anything.

        In other words - don't goof unless you want to totally waste your time. Start NEW, and treat it right from now on. In some cases, yes, an Optimate can do a VERY good job of revival, but it is not a miracle cure for the dead. Concentrate instead on commissioning your NEW battery, PM'ing it, and watching the test results.

        Comment


        • #5
          Can this charger do the balance on a battery bank? You did said you use it to balance AGM, my battery bank is 48 volts 8 of 6 volts batteries, if 1 or 2 cell out of balance and in different batteries at different part of the bank, how do I use this charger to balance the cells without moving batteries around? the batteries are 6 volts, I have to use two batteries for the balance? any suggestions?

          Thank you.

          Comment


          • #6
            Well, let's not go nuts here.

            The Optimates are designed for 12v / 6 cells in series. Normally a controlled overcharge (EQ for flooded), or extended absorb for agm will do that the canonical way and tend to balance the cells as some go into light gassing while the others catch up.

            Instead of an EQ or extended absorb, the Optimate oscillates the absorb by running it from about 14.0 to 14.3v, all the time watching the internal resistance and of course the absorb that does take place without having to go high-voltage. Essentially the leading-edge of the oscillation brings up the low cells without driving the high cells into extreme gassing.

            Without access to individual cells, how does one know? I built a 12v agm bank out of smaller Hawker Cyclons, purposely drained one cell (within reason!) and let the Optimate do it's thing. Expensive test, but fun.

            Thing is, you might be on your own when dealing with more than 6 cells, or some complicated parallel / series arrangment that this was not designed for. In other words, it may be helpful, but it may not be effective enough to justify it on anything more than a 6-cell / 12v battery.

            For your quest, I have seen "lead acid balancers" out there, (thowback to the Pb EV days...), but just like lithium bleed balance boards, all the same issues come up. Your best bet here is to find out WHY your batteries are going unbalanced in the first place, perhaps fix any high-resistance wiring infrastructure, do other normal Pb diagnostics, and see if you can accomplish the same with a normal charge that goes into light gassing.

            One has to be careful when shoe-horning a device into a system not expressly designed for it. It may work, and it may not.

            Comment


            • #7
              Originally posted by PNjunction View Post
              Well, let's not go nuts here.



              Instead of an EQ or extended absorb, the Optimate oscillates the absorb by running it from about 14.0 to 14.3v, all the time watching the internal resistance and of course the absorb that does take place without having to go high-voltage. Essentially the leading-edge of the oscillation brings up the low cells without driving the high cells into extreme gassing.

              Without access to individual cells, how does one know? I built a 12v agm bank out of smaller Hawker Cyclons, purposely drained one cell (within reason!) and let the Optimate do it's thing. Expensive test, but fun.

              Thing is, you might be on your own when dealing with more than 6 cells, or some complicated parallel / series arrangment that this was not designed for. In other words, it may be helpful, but it may not be effective enough to justify it on anything more than a 6-cell / 12v battery.

              That is what I try to avoid, EQ the whole bank that 4 out of 6 batteries are perfect balanced and 2 of the cell in two batteries out of balance. It put too much stress to the good ones and also waste a lot of electricity too.

              Thanks.

              Comment


              • #8
                what is causing one cell out of 3 cell out of balance? other than say factory fault? it is not like I can separate one cell to charge or discharge.

                Comment


                • #9
                  Yep, lack of access to cells is a problem.

                  At this stage, it may just come down to a quality / warrantee issue to be dealt with that way.

                  One thing I'd try first, is to *individually* charge those ailing batteries to see if the EQ will be more effective than trying to drive the whole bank into submission. Of course your other batteries should be fully charged before putting them back into service as a huge bank.

                  Note that I'm not a huge-bank guy, but a small sized hobbiest - seek professional recommendations!

                  Comment


                  • #10
                    Battery balancing question

                    I read recently that a better way to improve the balancing problem with batteries in parallel would be run equal length cables from each terminal to a lug, both positive and negative. Being careful to make the cable lengths equal.
                    The load would be connected to the lugs.
                    Does this sound like a better method for balancing purposes.
                    Then the question of charging these same batteries. Would be better connect the charging leads from the controller to this single lug instead of each batteries' terminals?

                    Comment


                    • #11
                      Sure it's possible and reasonable.

                      The worst thing to do is use a "ladder configuration". Here is a review of how to do it right for lead-acid:

                      http://www.smartgauge.co.uk/batt_con.html

                      .

                      Comment


                      • #12
                        2 battery charging- parallel

                        I read that run down thoroughly and it appears in my application that if I connect the load on diagonal post it would give me the best chance of keeping the batteries balanced.
                        Of course my situation is more of a charging setup and not one where the charged batteries would be used with an inverter.

                        Comment


                        • #13
                          You got it - avoid ladder connections to multiple batteries if you can, and at least use the diagonal.

                          Comment


                          • #14
                            Originally posted by PNjunction View Post
                            You got it - avoid ladder connections to multiple batteries if you can, and at least use the diagonal.
                            Note however that for for some battery chemistries other than lead acid the ladder connection may be preferred.
                            SunnyBoy 3000 US, 18 BP Solar 175B panels.

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