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LunaCycle Wolf battery parallel running while solar charging at the same time

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    LunaCycle Wolf battery parallel running while solar charging at the same time

    I'm setting up trikes with Bafang BBSHDs. I plan on running 3 LunaCycle Wolf 52v GA 13.5 in parallel. Ridiculously heavy touring setup.

    I have a 100W solar panel on each trike, with plans to add more on trailers behind each, which I previously used to charge a spare Bionx battery.

    Short system description
    Solar > Genasun GV-10 MPPT charge controller > 12.8V LiFePO4 40Ah battery > 12 to 26V boost converter > spare Bionx battery

    I'm going to build a junction box on the output side isolating each Wolf with a Schottky 80V 100A diode so back cross charging through the output ports wont be an issue, SAFETY!

    What I'm thinking is replace the 12 to 26V boost converter with a boost converter with 52/58V CC/CV regulation and running that into the batteries input ports which will also be parallel. I'm assuming that each battery's BMS will protect it on the input side and the CC/CV will control the charging

    Now my question is does anyone know if the LunaCycle Wolf BMS will allow charging/discharging at the same time? The Bionx system wouldn't allow this. If you applied charging current it disabled output current to the motor even though the system would power on. Thus charging the spare battery and swapping.

    Splitting the load among all of the batteries will maximize by distance because of the reduced load on each and add the solar charging will increase it further.

    Would appreciate any help on the BMS inside the Wolf's

    My other option would be to supply current in parallel to the batteries to the Bafang but prefer the charging option since it maximized my solar.

    Thanks
    Gadgets

    #2
    Far as I remember the battery has no problem discharging while charging. You can certainly power on the system while charging, which is a form of discharge even if just for powering the display

    Comment


      #3
      Hi paxtana,
      Thanks for the reply,
      My old Bionx system would do that as well. System would power up display on but it wouldn't send any current to the motor. Though the Bionx system was much more integrated system than this battery which will work with most ebike systems. I'm hoping that the BMS isn't quite as restrictive on this one. I suppose I'll find out soon enough.

      I'm going up for the install tomorrow. I have one set of batteries and just received the motor power supply side diodes today. So I'll be building a wire harness tonight. Don't have the mppt charge controller in yet so that part will have to wait for awhile. I will post an update about what I find out just in case anyone ever attempts to do the same thing.

      Thanks
      Gadgets

      Comment


        #4
        For anyone interested,

        I have the wire harness done for one of the trikes, still have to build the second one. Forgot to take a picture of it completed with heat shrink and spiral wrapping before I installed it :-(.

        Pictures are of the discharge side which is way more interesting than the charge side. I used 10ga wire along with hi-temp ring terminals. I crimped those with a hydraulic wire crimper and then soldered each before adding the marine grade heat shrink tubing. Rings are combine with brass screws and flex head lock nuts. Outputs are paralleled through 80v 200amp schottky diodes. The diode for each battery is rated at 100amp so I can still run the trike on a single battery and not worry about blowing it. Also nice with the oversized diode I'm only seeing about .1 volt drop so not wasting power in the diode.
        I know the whole harness is WAY over built but by doing it this way is that I'm losing less than 1% in the wiring between the batteries and motor. Trying to eke out every last mile from the system.

        Gadgets

        Comment


          #5
          That's a pretty cool diode, you got a link to which one you used?

          Comment


            #6
            Here's a link
            https://www.ebay.com/itm/Internation...Se9Bf:sc:USPSF

            Comment


              #7
              What a good find, that price is a lot lower than other examples I have seen. Thanks for the link!

              Comment


                #8
                You're welcome.
                The seller sent me the wrong ones the first time. Sent 45V 200amp diodes but he made it right with one email so would still recommend.

                Comment


                  #9
                  I can see the 3 packs in parallel for crazy range or high current. I'm curious with the charging setup why you are going with simultaneous charge/discharge. Would your bike run on one of the batteries alone? If so, could you cycle through them, switching from being charged to being used? The only advantage I see of running 3 batteries at once is if they were all low and combined they kept the voltage drop from triggering the low voltage cutoff.

                  Comment


                    #10
                    The reason I'm parallel the battery packs is to extend the range/battery cycle life further.

                    You can squeeze out more capacity the lower the discharge rate. Also the slower you discharge a battery the more cycles you'll get of it as well. So splitting the load across three batteries basically cuts the load on each battery to a third of the total draw. At 8A discharge, ie 500 watts, each battery is only seeing about 2.3A draw. Even at max draw for the Bafang BBSH 30A each battery will only be seeing 10A still below a 1C discharge rate which makes for happy batteries.

                    The wire harness will allow me to run on any single battery if need be.The anode, ie feed, side of each diode is linked to only a single battery but the cathode, outputs sides, are all connected together. This allows all of the batteries to feed power out but will limit the back feed between the batteries.

                    Sure I could cycle between batteries, which is what I did with the Bionx system I previously had on my trike. To put it simply it was a pain because the bionx system wouldn't allow for charging/discharging at the same time.

                    As for the question on why I want to charge/discharge simultaneously. When you charge a battery you lose about 20% of the energy you put into the battery. To charge a 13.5A battery you have to put in 16.2A. This isn't an issue when using AC to charge but when I'm using the solar I'm only going to have between 100-200 watts of solar. So right off the top you'll only get about 75% of a panel's rated powers at best. Which immediately brings me down to 75-150 watts max. Having to waste another 20% brings that number down to 60-120 watts. If the BMS will allow for simultaneously charging/discharge I'll get that twenty percent back since it'll pretty much just passes the power through to the load. Than if I'm not actively drawing current or drawing below the solar input it'll be feeding power back into the batteries.

                    Thus I get the maximum use of the solar power I'm bringing in. As for crazy range it isn't really going to be as crazy as everyone is thinking. Sure it'd be amazing if I was going through Kansas with a tail wind but living in a state with mountains my range is cut way down. It also doesn't help that my touring rig is about as far from ultra light as you could possibly get. Sure I could cut down on the weight but if I'm going to go to all the trouble I'd like to have a couple of creature comforts.

                    Beside everyone needs a Green Cheek Conure as a riding companion. Just ask him. He'll tell you.

                    Gadgets

                    Comment


                      #11
                      Holy shit look at that thing.. you got some more pics or video of everything you got going on there? Looks fascinating. Got to be one of the biggest builds I have seen and definitely the only one with a built in birdcage lol

                      Comment


                        #12

                        Of everything nope. I really should though

                        Comment


                          #13

                          Of everything nope. I really should though
                          A quick run down though. Well not that quick honestly.

                          Trike is an Azub T-tris, shimano Di2 shifting, Bafang BBSHD with 3 Lunacycle Wolf 52V batteries.
                          Solar panel is a Renogy 100w flexible mounted on top of a Ed Miller Big Leaf Canopy.
                          Right now the solar is routed through a Gensun MPPT charge controller to a 12V 40A LiFePo4 battery under the seat. When I get the time and money I'll replace that out with a fourth Lunacycle Wolf battery the harness is already built to accept the fourth battery and second load.

                          The reason I have it this way is because I originally built the trike without electric assist. Yes I was actually able to pedal this thing thanks to a Schlumpf mountain drive crankset and an 8 gear inch low. I was dead slow though. Wanting to up my range I went with a Bionx D500 and two batteries but the motor died. I think the motor was defective from the start because my wife's trike which is pretty similar in build was still working fine. I didn't trust the bionx any longer and wanted identical systems on both trikes so switched it out for the Bafang BBSHD.
                          The reason I started with the whole 12V system was I commute year round and the little green MONSTER comes with me to work every day. So I needed a way to keep him warm during the commute. Tropical birds don't hand the cold well, even if he's a Colorado native. So I found an electric bird heater and wired it up to keep the carrier warm and built the insulated cover for the carrier as well. So this progressed to running everything off of the 12V, lights, charging the phone/garmin.
                          The plan now is to have a fully 52V system and than us a bucking voltage converter to drop that down to 12V to run the existing stuff, but have to get the fourth Wolf and a new Gensun charge controller for that first.

                          I've included pictures of some of the stuff that I built myself for the trike and I've put comments on the pictures.
                          A couple need longer description than I can put with the pictures though.
                          The canopy adapters I made are pretty much self explanatory as is the solar panel mount.

                          The one that probably needs more explaining is the Bob trailer with a drum brake.
                          Since I weight just short of a semi truck I needed more braking power than the front two brakes only. Trikes normal only have front brakes because on a trike a rear brake is useless. Braking dynamics mean the tail lifts as you brake which means that even if you brake with the rear wheel it doesn't contribute much as the nose dives and the rear lifts. My trike is heavy enough that even under heavy braking my rear tire still contributes to the braking power. So I went about installing a Problem Solver brake doubler on the right lever. So this one now brakes right front and trike rear. I wanted to do the same with the Bob trailer and while I could use the Problem Solver to double the brake lever the issue was how to be able to quickly take the trailer off of the trike without having to redo the brakes each and every time. What I wanted didn't exist so I machined out the adapter you see below. The left brake lever goes through the Problem Solver doubler and than back to this adapter. I used a tandem brake cable splitter in the middle of this. So when I want the trailer I hook it up and screw the splitter back together and now my left lever brakes left front and trailer.

                          I was going about 18mph down a short hill and had to slam on the brakes. I stopped so fast that I actually triggered my Garmin 1030 accident detection. Though I do have to say that I miss the regen braking from the Bionx. It was nice to put it in regen 4 when going down a long grade and just let it keep my speed under control without have to use the brakes. If I were to redo this all over again knowing that I was going to go with the Bafang instead of the Bionx I probably would have had a small hub motor built into the trailer instead of the drum brake. I than would have used that as my electric no wear drag brake instead. Who knows maybe a project for another year.

                          Gadgets

                          PS while this video doesn't show the trike it does show one of my more interesting commutes home


                          Comment


                            #14
                            Got it. The system truncated my post at the point that I inserted an emoji via the Win+; shortcut even though it showed in the preview.

                            Here was the video that I mentioned. Sorry about the multiple postings
                             

                            Comment


                              #15
                              I was also going to mention in the last post but got distracted.
                              The other reason that I want to replace the 12V LiFePo4 battery is because right now I have two Cycle Satiator chargers. One for each 52V and 12V batteries with a twin output ac power cord. I stop plug that one cord in and it takes care of charging both batteries. Currently set to 85% charge for the daily commute but will switch to 100% when I get out and really start traveling.

                              With only a 52V system I can parallel both Satiators into that system and combine charge at about 14A. I can do it now but that involves my switching the output connector and changing the profile and I'd rather not have to worry about doing that. I run the risk of forgetting to switch it back and ending up with a dead battery as a result.

                              Gadgets

                              Comment

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