Good morning, all time to solder my bms, the high current stuff into um, basically an extension piece here - i put a fuse in there as well, and that means i can connect my solar panel to the battery and get charging it right. Let's put some solder in here now, i want the uh battery negative blue to be in this connector and then pack negative black to be in this connector, which you normally see on the end of a battery pack, and that will give me a bms protected battery Pack, i need lots of solder in there. Okay, so blue goes on this, sir one. Oh it's moving around.

I need some blue tech. Okay, i need to clean the iron because it gets very dirty very quickly because of the high temperature. Okay. Let's get that in there get some heat flowing, that's good! That's taken! Okay and i've got my pieces of heat shrink on here.

Let's do the other one and uh out here in the shed. I've now connected the bms to the battery cells, with the balance lead and the main current lead. I've got my solar panel outside connected to here that runs through this bulb and directly into the battery no charge controller, and it does work when the batteries fill up. This bulb switches off, hopefully i'll capture that and uh.

Yes, there. It is, and then, when the cell that's topped out, backs off and the bms switches back on the bulb comes back on now. I can't really see what's going on, because i don't have my balance. Charge leads on these two connectors.

So what i'm going to do is go back into the office now construct a cable for that, and then we can watch the cell voltages. While this thing charges up from solar gray here is most negative, black is most positive, i'll, try and remember that by it having the red next to it, these connectors will have to go upside down because the latching mechanism on there is on the bottom. So these must be the same. That's the four-way, that's the five-way! That should do it and there it is uh.

I've made the four-way slightly longer because it has to reach over to the other pack, but let's plug it in and see if it works. The battery checker is now on here with my lead that i've made up, so i can see the eight voltages all the time. That's good sona's coming in here. I think, there's a cloud going past at the moment, through this light bulb through my ammeter, see.

If i can get that a bit more into shot, and so if i connect now, that's positive, positive positive. If i connect that to there uh the lamp comes on, i'm charging the cells, the bms is ultimately monitoring and will cut off the charge if a cell goes too high now what's happening here, we've got one at 3.6. Oh, it's climbing up quickly! That cell 5 is at 3.65. Now now the bms is a bit tardy, or at least its high setting is a bit high, doesn't actually chuck off until about 3.75 interesting, but at least it shuts off now.

The point about this is that uh self five, which actually is that one at the back on the top there is way ahead of all the others. So it's high now i don't know whether the with balance on this bms is actually going to do anything very much. I think it would be better if i set up a charging and balancing setup that isn't running off the solar for the time being, or at least for as long as to get these cells into balance, because they're clearly way out. I'm not sure when this will cut back in uh.

The highest cell is still cell 5 at 3.58. So i'm waiting for that to drop down to whatever threshold the bms decides is low enough that it's going to switch back on, i'm tempted to say 3.55, but i don't know um. I will wait until that happens until this lamp comes back on and then i'll restart the camera it's come back on. I just want to check the current and it was around an amp, it's falling, probably because of the differential between solar panel voltage, which i can see actually oh well, it's 33.3 volts now because the bms has shut off, the lamp has gone off.

That's back up at 3.73, so clearly, this is not a very good setup. I'm going to rearrange things a bit. This is my new setup. It's the isdd isdt t8.

The balanced charge lead is now going into that. Its output is going into the uh. Well, the cells via the vms and i've got 12 volts on here from a power pack. So i'm going to do um.

We can see the voltages so they're upside down. It's the only way i can arrange this um yeah cell 6 is 3.57 cell. 5 is 3.60, so that's the high one. So i am going to do a uh lifev, 3.65 volts, 8s half amp charge.

Let's get that started, i'm doing it at a very low current, because that way the balance charge circuit in here and it's quite powerful. I think it can do up to two amps on these. It won't at a half amp charge, but it's going to be able to keep the high cells in check at this current. So it's pulling the high sales down.

Uh cells, five and six are now 3.50, but it needs to get them down to 3.39. That's the lowest one, get them all in balance and then bring the whole pack up. Well, really slowly at half an hour. These are 10 amp hour.

So, theoretically, it's a 20 hour charge. These are probably about half charge this one. This pack, actually, i think, is quite near the top. So maybe it's six seven eight hours doesn't matter to me.

I'm just gon na leave everything out here and get this pack charged top balanced so that i'm ready to go back to charging it from solar. I've mounted the camera upside down so that for the video it should be the right way up or near enough. Oh, the exposure's still not quite right, isn't it let's get that right down like so so you can see that it's quite good at pulling all the voltages together. That doesn't mean that the state of charge of all the cells is now matched it's just putting some resistance across the necessary wire pairs here to pull these all together.

In fact, it's hinting that these cells are higher. I don't quite know what it's saying there. Everything is now at 3.41 that one's at 3.40 - and it's just case of leaving this now um for it to very gradually bring everything up to three point. Six sigma takes five is probably where it'll terminate, but at the same time, holding down the cells which are clearly well ahead of the others, so yeah, this t8 is doing quite a good job, but it will be a very slow charge yeah.

This is interesting. Why did that suddenly change the exposure? Get the exposure right there? It is. It's got the same cell voltage for each cell or near enough, but it's definitely got longer bars for these two. So is it doing some sort of i'm anticipating because of what i know from historical events that actually these cells are have a higher state of charge? So are these bars more than just voltage bars? They must be, they must be anticipated state of charge bars.

It's quite clever that but um it's certainly managing to hold these cells down to these voltages, while it brings all the others up. So i think this is going to work. It's just going to take a long time. Oh i missed it.

The uh display has gone blue, but it has now, if i come around here, balanced all the cells, it's beeping, because it's telling me it's finished the charge they're all falling back now. Cell 4 was a bit of a laggard, and indeed you can see from that. That it's falling back the quickest. If i keep restarting the charge at lower amounts of current, i can probably um sort of get it to match up with the others, but it doesn't really matter.

Essentially. The t8 has now filled my eight lithium ion phosphate cells completely and really the next thing i need to do, and i've started to think about this. I found this power supply, which was probably given to me by banggood a few years ago. It does 15 amps on the output, so that should be okay to step.

The 24 volts from my lithium ion phosphate down to the 12 volts needed for my ant miner at a reasonable current. I don't think i'm going to be able to run it with all the hashing boards, but i can certainly start by running it with one. So the next thing is to make up some cables um from here to that power supply and from that power supply to the miner and empty all of these cells until the bms says that's low enough anyway. For the moment, my cells are all fully charged awaiting the discharge machine, which is the ant miner uh, which is coming soon, that'll be the next thing i work on so for the moment, cheerio.