Good afternoon, all these are ideal diodes. Now i don't know whether you remember, but a few years ago i bought a whole set of these ideal diodes and i've never actually used them, but i have an application now where i think these might come in handy. So i've got my solar panel hooked up to my lithium ion phosphate battery, and i noticed that after dark this, the battery is feeding back. It's feeding a small amount of current back into the solar panel, i'll insert a clip showing me or showing that happening, not completely dark yet, but certainly very gloomy.

Let's head into the shed i'll need some light. That's that light and let's turn on the ammeter and yes, we're getting minus 20 milliamps. So you do get back feed from the battery into the solar panel, only 20 milliamps, but it's not zero. So what i want to do with um these and i'm going to choose this one just because it's got these convenient terminals is put the solar panel on the in positive and in negative connections and the battery on the out positive and negative connections.

Now. Is it safe to do that? Is it safe to put a battery straight across the output of this thing? I suppose i ought to have a look at how this thing is wired. Yes, i remember now this doesn't work and it can't work and i'll show you. It's not working actually so there's five volts of battery going into the in there's a 24 volt bulb, which is not very bright, going coming out of the out um.

But what i really want to do is measure the voltage drop. So, let's put it on volts measure, the voltage drop and it's 0.6 volts. So that's not an ideal diode, that's a diode and in fact all it's doing is it's using the body diode in this pair of mosfets, which are in parallel um to act as a non-return, anti-back feed thing. But it's not an ideal diode.

It's just a diode and it will get hot, hence the heat sink, which i must have pulled off last time. I looked at this, so i'm going to use this. This is an ideal diode with an ltc uh. What is it four? Three, five nine.

So it's a special controller chip which controls these four mosfets. Now it looks like these are all in parallel, or at least all their sources are connected together, but the drains on this side go to the out and the drains on this side go to the in. Not quite sure why it's been done like that, but anyway um. I just want to see if this works now.

The other thing is. Can i put the output straight across a high voltage battery 24 volts? I mean this device says: oh, this is an ebay list. No, this is an aliexpress listing, uh 4 to 70 volts so and 15 amps without any heat sinking, so that should be okay, let's wire this up to a couple of xt 90s. So i'm going to wire it like this, i'm going to put an xt90 19, not for the current, but just because it's a convenient size and it's what's um on my solar panel lead um positive, a red wire to the in positive red wire to the out.

Now the black wire i'm just going to run straight across, but then i'm also going to solder in a little thin wire which runs up to ground and that's because there's no high current ground running through this board. All it needs is a ground reference. So that's uh that could be a little small wire and i just want to make the point about that. So i'm not actually going to connect the fat ground to this large hole, i'm going to connect a thin ground wire to that little hole.

Let's do this, so i bought this red wire got some black as well. Now. What is this? This is awg 12 awg. Oh, you may not be able to read that, but that's what it says: 105 degrees c uh.

This is try rated. So this is what i'm going to use for the positives, and then i've also got some black i'll run that straight across with the negatives, with my little additional wire, the chap on the ebay listing said um 41 amps for this, and of course i don't need 41 amps for the project as it stands, but going forward and that's got to go through that hole that might fit in there. I think i'll make an extra long, uh removal of the sleeving for that one, because that's going to go into the xt90. Oh, that could actually be longer still, but anyway, that's good enough for now i'll use the ts 100 for this on 400 um degrees, because that ryobi iron, i don't think, is any or much more powerful than this in terms of what so this should do this.

Yes, just about okay, we need to tin the wire. This short, no, that's what i didn't want to happen. I didn't want it to splay. This short piece of wire is going to get very hot, very quickly, of course, but that's all right i'll just have to deal with it.

Yeah! It's not really powerful enough for this. Okay, let's shove that in there - and i want the curl coming up because i'm going to come up from underneath on this board. Okay, let's see, if i can get this in there with minimum drama, that's it that'll do now. I need to bend this 90 degrees.

Is it still too hot to uh to put a curve in there? No, i think it's about right and then that needs to go through this hole here, get all the strands through the hole they don't. Oh there. It is right, let's solder, that and hope. I don't fry those components right: here's my big piece of black not attached to the board and a thin piece of black, which i can put in that end mustn't forget to do that.

But first i need to solder this end flood it with solder, get it to attach itself to the connector which it hasn't done. Yet i think it's just starting to in you go, try and keep a large amount of surface area in contact with everything there. It goes it's flooded in so that's that side. So if i put the heat shrink on there, okay, let's get the negative side in so i've got my thin black wire running over the top.

It goes through the heat shrink, so i can heat shrink it all. Together, but it is sitting a little bit in my way of applying heat down onto the thick cable - oh well, let's just flood it in yeah. It seems to be attaching itself to the connector of the xt90 come on flow into it there. It goes that i think, is okay and there's my final module with an in a socket and an out plug.

Well, that's actually a socket, but that's the way it's done. Uh there's my thin black wire running up to the ground point there and then the thick black wire just runs right across. So that's my ideal. Diode solar panel goes in there and this will go to my 24 volt lithium ion phosphate battery do my bulb and battery test again and that lights up so current goes through that way same as the arrows and the other way it shouldn't light up.

So they're shoved in there that's shoved. In there i mean it's not going to light up, so no amount of wagging is going to make that work, and so this is it in position. Uh solar panel is there comes through the ideal diode into the battery i'll. Just change the angle of this uh yeah through that bulb just as a sort of protection against something disastrous going wrong through the ammeter.

Now there is only 280 milliamps coming in from the solar panel, because it's very overcast today going into the battery these numbers should be lifting up. I haven't seen them lifting up, but i'm sure they are a tiny fraction with that very small current. What i want to see is when it gets dark this evening, um whether there's any back feed current back through the ideal diode and, of course there shouldn't be now. If you're thinking julian, you don't need that ideal diode, because there's going to be circuitry in the mppt solar charge controller, which you're eventually going to use to charge these batteries.

So this is a bit superfluous. Well, these batteries sit at about. In fact, i can show you um 26 volts now the maximum power point um of the solar panel is about 28 volts and it runs through 28 volts when you charge this up to its full voltage, which is something like 29 volts. So actually it's a very good match between a 60 cell solar panel, which is outside and an 8 cell 24 volt lithium ion phosphate battery pack, so you're almost at maximum power point over most of the charging curve.

It's going to start a little bit below hit maximum power and then just tell off a little bit at the end. But it's so close that i'm almost tempted for at least in the medium term, not to bother with mppt i'm just going to connect the solar panel directly to the battery. Through this ideal, diode we'll see how that goes. In fact, this ideal diode isn't really massively necessary because the back feed current of 20 milliamps is very small, but it would just be nice to see that the backfeed current is now zero.

There isn't any backfeed current um, which i'll do when we lose the light. Um in that fact, i was just thinking. I have here a big piece of cardboard. What say i go and shove it over the panel now and see what happens on that meter.

Let's do it that's only partially shaded, but oh yes, that has gone to zero. That looks pretty good. It's dark! Well, almost solar panel, nothing much going on there head into the shed, let's put some light on, and what have we got back feeding into the solar panels, precisely nothing because of the wonderful new ideal diode, which stops the 20 milliamps of back feed that i had When i didn't have the ideal diode so that solves the backfeed issue, not that it was really an issue anyway, but now there's none another day very hit and miss with the sunshine. Today, let's look at the cloud situation.

Ah, yes, sort of on and off kind of thing, let's head into the shed - it's all very damp out here, so i've got this set up now, with um, a 55 watt bulb in the circuit there, which is effectively pretty much a dead short and the uh. What's it called the ideal, diode is fine, just put my finger on it, see if there's any warmth, no stone cold, we're up to the 3.4 region. I had mined away with the ant miner here, some of the energy contained in these cells just waiting actually for the sun to reappear, and then this bulb will go from a faint to glow in there, too, really quite bright. If you're wondering what the noise is, i am mining today because there's quite a bit of sun with one of the l3 machines.

This is l3 plus um on ip address 1.43. Yes, these are so much more lucrative than something like this z9, which is oh there. We go look bright, light yeah, it'll, be a shame when the l7s come out and rather spoil the party for those l3's. Oh the sun's gone away again, so it briefly came out.

Oh it's really gone away. Look that's gone to a very faint glow. Wait for the sun to come back out and for that to go bright again and there it is. Oh there it was and uh when that happens, all right again, it's very on and off today um.

Then, of course we get lots of current we're. Looking at two amps at the moment, but that's gone dim again uh, but these are pushing up to the mid 3.4s. Oh extremely bright. That's 2.89 amps 3.45 on the highest cell, which looks like cell seven, so yeah that won't take a long time to what i really wanted to do.

Today, though, we'll see whether this ideal diet gets well. No, it doesn't it's absolutely fine. I think that could take well, certainly 10 amps. It says it's rated up to 15 and there's no heating provided with it.

So i think that's absolutely fine in this system. This, i think, tops out at about eight amps. That's if i took the bulb out and put a dead short between the solar and the battery and um zero back feed at night, so that certainly solved the problem. The back feed, not that it was a particular problem.

It's only 20 milliamps. I may not need it at all, but this video was really about that thing and whether it's of any benefit - and i suppose it is a bit so i think i'll wrap it up. That's the end of the video cheerio.