Good morning, all this is the xtar bc8 aa sized battery charger and xtar have also supplied me with this 18 watt wall adapter. So let's open this package up like so now, xtar have also very kindly supplied these two 1.5 volt lithium ion rechargeable cells manual. Is here and it's pretty straight forward: we've got indicator lights, which are just red or green, so charging or charging complete um. It takes 1.5 volt aaa or aaa lithium or 1.2 volt a or aaa nickel metal hydride, and you can mix them because each bay is totally independent.

Um charging function stuff your batteries and they start charging. There really isn't much more to it than that. So i will charge these um supplied lithium aas, and i also have some ladder which are from ikea. I've got some 2450s and i've also got these ladder.

These are the 1900s. Now, normally you wouldn't choose to buy batteries that were a lower capacity, but these have another advantage, and that is their slightly smaller diameter. You can see these ladder 2450s, don't actually fit terribly well in here they're a bit of a tight fit. I suppose you can get them in no, you can't push one in the other one pops out now.

The charging current of this battery charger is half an amp 0.5 amps. However, it does say down here that when the power supply is insufficient and that's because it only pulls two amps from the usb, so there it is loaded up with three of the larger ladders and three of the smaller ladders and the two x tar, 1.5 volt. Lithium i'll use the cable that came with it, plug it into a power bank and we'll get charging now. This supplied cable is a usb type c, one end to a type, a the other, but it's colored orange as a sort of hint that um you should be using quick charge three well.

This power bank has quick charge three, so that should work. Let's give it a try, so that's it plugged in and charging all the lights are red, so they're all charging. Now the ladders, these white ones are full. These gray ones are completely empty because my stair light had gone really dim last night, and these two, i think, are full because i charged them in this charger yesterday.

So let's have a look at the voltage and current that's being pulled by the power bank. So i'll just take that out momentarily stick this in. Oh, it's the other way up in there and let's see what the numbers are and well, it hasn't gone to 9 volts, which is interesting, maybe actually the 9 volts is on the green connector. I don't honestly know on this power bank that hasn't gone to nine volts either and i've just tried a different power meter, and this is also running at five volts, so the battery charger hasn't pulled nine, i'm just wondering.

Actually, i think these cells charge up to four volts, because i think when, when it charges these cells, it charges them because all that's inside here is a 3.7 volt lithium ion cell and a little buck converter board at the top. But i got a feeling these charge at the full voltage. We can test that i'll put a d dmm on there. I can't get the probe down to the positive, so i'm going to use an led just so i can use its leg.

Let's measure that no, i still haven't managed to get onto there. That is still red. Isn't it yeah? So that's charging! Okay! Yes, 4.29! Oh that's! Quite high! Isn't it 4.29 volts? What's on the other one? Maybe this is import! Oh no! There we are 4.5. That's very high, isn't it is there some sort of internal resistance element inside these cells? Yeah? 4.5? Well, that one has now gone green now, it does say on here end of charge, voltage 4.20 plus or minus 0.05 volts for lithium.

Oh, you can't see that and 1.45 volts plus or minus 0.1 is for nickel metal hydride right now. I've plugged um the supplied charger, which is, i presume, 5 volts or 9 volts into this unit, and it has taken it up to 9 volts. So maybe that power bank had some sort of issue with the quick charge 3, but this supplied adapter is supplying the unit with 9 volts, so pretty simple: to use no adjustable currents, no voltage readings, just red and green lights. So i think what we need to do now is take this thing apart.

So let's get all the cells out and i've noticed that there are six screws on the bottom, so let's take them out and have a look inside. Incidentally, this thing about the diameter of the cells. This ladder 1900 fits in my fenix torch. What is this thing? Fenix e11 um, with a bit of rattle there.

The 25 2450 fits in there with a bit less rattle. Now this um 1.5 volt lithium cell. It's a bit of a tight fit and it's also its diameter is not entirely consistent all the way around, but it's it's probably too tight a fit to fit in there with some guarantee that i'm going to be able to get it back out. Let's try this fenix ld15 and yes, it does fit in there, but you have to be a little bit careful with some of these cells there that are a little bit wider diameter.

Sometimes they don't fit in things. Okay, let's remove these six screws from the bottom of the unit, which i'll just have a quick look at that uh. It probably says much the same, as is in the manual uh interesting: 1.5 volt lithium-ion battery output. This says 5 volts, uh 0.5 times eight pieces, which would be uh four amps, wouldn't it at five volts, so it would have to throttle the current back.

I think, for that 1.2 volt nickel, metal hydride output, 1.45 volts is where it stops. Charging now don't know whether this does a delta v thing. Looking for the top of the charge voltage it may not, it may just be simply charging to 1.45 volts, which is probably okay to most nickel metal hydrides right. The six screws are out inside.

We have this, yes, i suppose, with a huge hole in the middle of this thing, this board had to be split into two parts. Now, how easy is it to take these out? Are they fixed in it? No, they don't appear to be fixed in uh, but it's probably going to require sort of easing this out. I know that's come out quite easily, okay, that one's out. How do i get this other one out? Uh? Oh this: has these metal plates slid up into grooves? That seems to be coming out and there it is well the board.

With the negative connections. You've got the uh double a negative connection and the little aaa negative connection down there. All that appears to be is eight connections running back to this eight-way ribbon, cable and running back to the main board. So there's very little to say about that board on this board we have a chip here which we'll take a look at in a moment.

Um there are eight inductors here with really only one other than diodes one active device. So i don't know whether that is an individual buck. Converter we'll have to take a look at those and then on the top side. Now there are these 16 pin ics, but they've all got no markings on them.

There's another 16 pin ic there. So five ics, maybe that's a controller, and maybe these are uh charge, purpose built charger chips. Perhaps a dual channel. Uh we've got some leds up here.

Diodes and there's a big inductor wrapped in heat shrink here, a couple of capacitors electrolytic, and that's really all that's on here. So, let's i can't tell you what these chips, unfortunately, are, because they have no markings on them, but we can look at the ones on the bottom. Well, it looks like the little three pin. Stop23 is a d05lg, so we'll look that one up and this eight pin sig is a cx.

Eight. Eight five five is that. Well, i can't find anything on the little 23 uh controller chip there, but i have found a data sheet for the cx-8855, just printing that out now right. Well, this dead sheets are largely in chinese, but we've got a few things here.

We got 5 volts, four amps uh, eight pin chip and the application circuit shows it with an inductor. Well, that will be the big inductor. On the top side, the one in heat shrink there there's a little current sense, resistor there, which is on here. It's there right next to the chip and then the usual suspects output capacitors here, which are these two on the top side.

So that's it really! It's a simple to use charger, uh no functions to adjust or switch, but it does charge both your nickel metal hydrides and if you have them these 1.5 volt lithium ion cells. So that's it really uh! That's the xtar bc8 nickel, metal hydride and 1.5 volt lithium battery charger with usbc input now i'll put a full set of links and information down in the description below, but for the moment cheerio.