Hi back in Eevblog number 35 Yes, that was in a Galaxy far far away. I Tore down had a look at this Vada fast battery charger and four nickel Metal Hydride batteries. It can charge them in 15 minutes and we took a look at that. Well I've got the new one, the upgraded model to this thing so I Thought we'd just tear it down see if any things are changed between this original model and this new one.

Let's check it out. Now the first thing that's changed between these is the input plug packet right in. The old one here had a 15 volt DC plug packet 4.7 Answer: Basically 75 watt plug packet was actually supplied with this one. even though that charge rates exactly the same is only supplied with here.

It is a 45 watt plug pack. It's the same 12 to 15 volt input. You do actually get a car charger lead with it so you can actually recharge your batteries 15 minutes in the car which is very handy, but it's only 45 matter what's maximum plug pack. Still, that is a decent sized plug back.

I Am I The only one who hates plug packs with these stupid ears on them. Why? what does that do? It's just a pain in the ass. It just fails with ones next to it. And the other main difference is if I pair it on, this one has a funky LCD here backlit blue ooh fancy pantsy that's got our individual voltage and current readouts for the individual charging on each cell here whereas the old one just had you know nothing at all, just four.

LEDs That's it. Bob's your uncle and it had these rather nice little contact terminals here. and just like the old one, it's got a fan in here. It has to to keep these things cool so that just starts.

Sucks that in from the bottom. I Do like this design here. If you put the batteries in like this, it's um, it just allows you to get your finger in there and just pop it out. That's a really nice touch.

Anyway, it needs a fan. and because these batteries are going to get hot, you can charge these up to 70% of their cap the in 15 minutes. It's got an 8 amp charge rate. Unbelievable.

And for those who haven't seen it, here's the voter ready to use. They call them rechargeable nickel metal hydride batteries. They're basically equivalent to the Seor any loops, which everyone knows. these are long life batteries.

These particular ones, can you charge them? then? they still retain that 75% of their charge after a year. Not quite as good as the latest generation any loops, but you know, not too far off it. this is 2100 milliamp hours capacity. This is what came with the charger, but they are available in up to 2600 milliamp hour capacity.

But the amazing thing about these is that well, these batteries and this charger is that they actually charge at 8 amps 4 times what's called 4 C or 4 times the capacity rate in almost um, you know 20 100 milliamps times 4 is going to be 8 point a 4 but near enough to 4 C whereas the Segno any Loops the fastest charger I've seen and please correct me if I'm wrong is just 1 C or even I think CEOs fast charger in quote marks for the Segno any loops is just under 1 C or something like that so takes much longer to charge the Yahtzee knows. but I suspect there's actually nothing special about these varta ready to use ones that enables are fast charging I reckon you can probably do it with the inner loops to I think they're actually pushing these things beyond their you know I Don't want to say beyond their design capability, but you're not going to get the I don't think I haven't tested this but I don't think you're going to get the claimed number of recharges on this if you abuse them basically by charging them at 8 amps but you know it's still going to work. you can actually charge these super quick now. I tried but I couldn't find it.

so please, if you can find it, please link in the datasheet to these Vard ready-to-use batteries. I could not find it for the life of me. Maybe I'm just dumb and I missed it. But anyway I got the senior any loop ones here and it says the faster start charging right here fast Charge is so 2,000 million taels for basically a two thousand milliamp our typical cell.

So it's a 1 C charge rate, so it doesn't say that you can actually charge it any faster than that, presumably because that's what their specification is for the 1500 recharge cycles or something. You know you've got to charge it at 1 C. But if you have a look at the charge and discharge curves here, it does actually show you a look at the charge rate are two thousand milliamp so one C. But of course the discharge curve.

They actually have a discharge curve for to C or four thousand milliamp. So if you can discharge it at four amps, why can't you charge the thing at four amps? So it basically you know they don't tell you this in the datasheet, but it comes down to the fact that these nickel metal hydride batteries be at the seniorita loops or some of the others, or these vital ones can most likely be charged at a higher rate a much higher rate than the one C But you're probably not going to get the full number of recharge cycles out of them. But if you don't care about that, you want your batteries charged in 15 minutes or half an hour or whatever, then you can probably do it. now.

This charger is really funky. Not only does it have their individual our cell charging which the cheaper Vaada battery charger for these things are there which is like half the price does not have you have to actually put two in series but of course that's not going to work when you're charging the damn things at 8 amps like this puppy does. So it's got individual cell charging, individual temperature sensing which as we saw in the previous model and I'm sure when we do the teardown in a minute will find individual are temperature sensors connected directly onto the pads down in there or may or probably I don't know. yeah maybe this one down the bottom or something like that.

it's got to be connected right on there to get the thermal heat transfer right. You know, as efficiently as possible down through the temperature sensing because that when you're charging them a super high rate like this, it's critical that you measure the temperature so you have individual cell temperature are cut off with this thing as well. And yes, this can do double A's and triple A's and triple A's that charge at a nominally slower rates. It's got a separate contact down in there and but the great thing about this charger is we'll walk it in and here we go.

It's charging and it's actually got eight thousand on there. So it's actually charging it eight amps and we can actually put two in and we'll charge two at eight amps. but err, it won't do. Our plug pack cannot supply the power, the internal charging circuitry cannot handle it if you want to put more in.

Bingo! It changes them all to four amps out halves. But you can charge all four at four amps or twice at to see, but you only want two of them. I Like that. just get your finger under.

That's a beautiful design. It's absolutely beautiful. Look at that in any of the combinations of the spaces. Here you can get four.

C Charging Absolutely incredible. and I'm not sure if you can hear that fan going. It's not massively loud I Think the old one was louder, but it is distracting if you use it in a quiet environment. But it's got it.

You've got to get the airflow over these to attempt to at least start. cool these things down because that is a massive charge rate for C Now it's actually got different display modes That was a charging current. Now we're looking at the charging voltage. here.

These are already yet charged. it's probably about to cut off any second. I'm not sure what the what cutoff voltage that they're going to cut off at, but very close. And it'll also tell you why the accumulated charge as well.

There we go. 137. It's counting up. So how much charge we're actually putting into these things.

It's able to measure that. and if you have a look at the modes here, it's charging at the moment. Well, we can change it. We can actually discharge the batteries as well, so it's going to have a load inside there that we can now discharge the previous one I don't think you had that.

It was just a purely a charger, so that's very nice. But not only if we got discharge mode, we've also got that refresh mode as well. And what refresh mode will do is it will actually discharge the batteries and then recharge them. Just so you know, like cycle the batteries so it attempts to get some extra life out of it.

Whether or not that's you know it's going to do the business. I Don't have to go into the chemistry of the the electrochemistry of this particular type of art, a battery and whether or not it's worthwhile. But anyway, you've got that mode and you've also got test mode as well. And what test mode will do what it's doing now is it's showing Mm.

so it's discharging at 2 amps, discharging these battery as soon as it's finished discharging. Just like the Refresh mode, it'll start charging up again, but when it charges up, it will actually calculate the add up and calculate the accumulated capacity in the cell and it will give you a readout for the milliamp er capacity of the cell. Once it like it's going to take some time to fully discharge this at 2 amps and then recharge it. but hey, we can.

Actually it's a battery capacity tester. Fantastic. But hey, that capability basically comes for free because it's basically a software function. Once you add in the ability to discharge these cells, well, it's just you know, a micro software stuff that just calculates the milliamp power capacity and can do that sort of stuff.

so you know no surprises that they've added that. And naturally this thing has all the bells and whistles that's got to be safe in terms of our charging. So it's got dart negative Delta V cutoff and it's going to have as I said individual temperature sensors on the contact terminals here. So it's going to have temperature Delta cutoff as well because you know once these batteries hit like I believe it's like around about 1 or 2 degrees C per minute temperature change, then you know they're there.

Basically I reach their full charge and you need to cut them off immediately. You don't want these things to go are completely exothermic and explode on you and that is a poor attempt to try and keep us out. Now we can fix that security screw and I can get these ones out, but unfortunately the hole down in the shaft down in there is just too narrow to actually fit the entire shank of this thing. this security bit in there so it doesn't work.

but here's one: I Prepared earlier. Nothing you can't fix with a Dremel. and today there it is. we're in like Flynn and it wouldn't surprise me if this is a very similar or the same as the previous model.

although we didn't have that quad flat-pack last time. I Don't think we can see where they've removed solder mask all around here. that's to well and then to get some much solder coating on that just increase the current handling capacity of these traces just a bit. You don't want to spend extra coin for a row, you know the two ounce thick copper on your PCB no siree.

Bob So you just remove some solder mask and let the solder coat do the business. They're not as effective as you know proper thick copper, but me does the job and this ball is actually fairly easy to lift out. So it's a double-sided load. and today we can see there's our MOSFETs obviously down in there for our individual are driving channels.

We've got two per channel. horrid here. or is it one separate one? one for a double-a one for triple-a contacts. I'm not entirely sure we've got right angle charging contacts on there.

Here's the springy ones at the back. There's nothing fancy going on there, it's just you know, spring metal. and bingo there is. Our temperature sensor.

Looks like they've got diode temperature sensing right down on the contacts down in there. You've got to have that for a fast charge like this. Absolutely critical, otherwise your batteries will explode and catch on fire. And just a silicon diode.

Temperature sensing like that? You know it's good enough for the crude type of stuff we're doing. You know it's roughly what is it? 10 millivolts per degree? C Temperature coefficient. If memory serves me correctly, for a regular silicon diode, it's just good enough. You know you you want to measure that temperature differential that change over you know, over the span of a couple of minutes Soap? You know you don't have to be.

You know point one percent accurate on your bloody temperature. so you know they're going to do the job actually. I Think I'm going to stand corrected on that. It's not a silicon diode.

It's a do 35 hour glass package. similar to what some diets come in, but NTC gives it away here. Negative temperature coefficient that indicates this is a thermistor and you can get the misters in do thirty-five glass packages like this. so that's what it must be.

So they're not just using a silicon diode and this might look a bit strange here. How is splitting around these contacts here? But what they're basically doing is they. you know these. These pads are shorter.

They might look like there are like Isolators some sort of you know, four terminal sense measurement or something like that. but that's not the case. They're actually shorted out just like this one. You'll notice that all the copper is basically this terminal here.

They're using all of the available space right around here. so this is this trace here on this side is for this terminal here and this one on. But if we can flip it, can we flip it over I'm not sure. Yeah, but yeah we can.

There we go. and this one here is using this top side. Okay, so this one goes on the bottom side. This one here.

it goes on the top side all the way across. And likewise for these two over here, you'll notice that this one here is for is it for this terminal here? Yes, it is. And all this on the bottom here is going to this terminal over here so you know that they have to do that. They've got to fit around the fan.

You've got this huge big cutout for the fan which is absolutely mandatory. You've got to have it right over the batteries. so they had to use all the space there and they can just snake the little temperature since terminals right around the outside. they're just now.

This is interesting. These two pins here are the triple-a terminals and these two here are the double-a E terminals and you notice there's just some parallels resistors there. There's actually three on this side and they are they one our zero? 1 Ohm I Think they're they three 1 Ohm resistors in parallel and it's got another three I think on the other side as well and I Can't actually see any voltage tap directly off the Double-a terminal either on the bottom here or the top. But what they're doing is you can actually see this trace here going from our 79 there that is actually tapping off right onto the Triple-a terminal.

which if which is fine. Okay, so your voltage sensing the you know, four wire terminal sensing so to speak, the Triple A terminal here. But if you don't have the Triple-a battery installed, then these 1 Ohm series resistors or less because you got them in not parallel. you know, sub, You know hundreds of millions in series is not going to matter.

So you're essentially directly tapping off the Triple-a terminals as well. That's neat, so they're not. You know, then not bothering to actually tap separately, the Triple A and the Double-a you can actually do it in one. that's actually quite elegant and you can forget about finding out what that presumably it's a micro.

It's got to be like a off-the-shelf micro. but then they've rubbed the numbers off it. So and all their you know, the hand solder connections are very how you're doing. Quite ugly, you know, very messy work.

I'm not hugely impressed by that. and you can see the UH solder thieves there. Those are those pads. Those large pads.

These are designed so when this thing goes through wave solder in our process then it just bleeds some of the solder off there. All our thieves the solder away so you don't get shorts on the rest of the pins. I've covered that in previous videos so obviously this board was that way. Sold.

It needs to be wave soldered to get all the extra solder on these iPads here. So double-sided. All these components would be a stuck down with glued. yeah, you can actually see the glue just oozing out from the bottom of those parts there.

so they're going to stick those down before they wave solder this thing of course. Otherwise they just float off in your solder bath. That'll ruin your day. and we got ourselves a tail for 9/4 Not a genuine Texas Instruments It's a UTC one.

but ant, whatever. that's a pulse with the switch mode controller and that's handling or the switch mode on top. We've got to have a switch mode Biggers Massive amount of power involved here so that till Four Nine, Four under there is controlling our switch mode controller here. We've got a massive inductor on the top here that looks quite nice.

I've got a switching over there, is it? Yep, and that is an SPD 50 Po3 for those switching 20 fan waise there you go whoo and the load control MOSFETs in there there's a new one DTM 44 1-0 from a manufacturer I've never heard of and I think Din Tech, go figure and check it out. We don't need no stinkin' common mode joke. Note: We'll save a couple of senses. put a couple of links in there.

she'll be right mate, No worries. and I love this here. Look, they've put in this link from over here. they went: PCB Designers went nah no I can't get enough width through this channel I've got to snake this signal connected through here.

damn it can't meet my current trace requirement with that particular width. and well, they won't let me spend the extra dosh to buy two ounce copper board. so I will just whack in a link. She'll be right now.

I've done a little bit of reverse engineering on one of the channels here and it's a rather unusual arrangement. What we got is two N channel mosfet s-- like this across the battery holder, directly across the double-a battery holder and we've got our DC to DC converter and which I believe is a constant current source and it's going into the center tab of this kind of like for want of a better word, a totem pole type arrangement. here. and I've drawn in are the internal body diodes of the N channel MOSFET and if you watched our previous videos I've done, you should know that N-channel MOSFETs or MOSFETs like this have a what's called a body diode.

a parasitic diode inside. Its inherent in the physical construction of the diode itself, and I won't go into the physics of how it happens, but it's basically a reverse biased diode like this and you know you might think, okay, what they're doing here you might think is actually quite clever. They're actually this is a constant current source currents flowing into here. and you might think that because this is an N channel MOSFET, they can't turn that on.

and they're actually using the body diode like that to force the charge current through the battery like that. But that's not really what's happening. This end channel MOSFET will actually are turn on. It's not a more typical arrangement you might be familiar with because obviously the voltage of this, the output of the DC DC converter, the voltage here.

the compliance voltage right there is going to be larger than this double-a battery. Okay, so you might think that you know they should be using a P-channel in here, but an N-channel still going to work as long as the Vgs the gate source voltage. This is the gate terminal. This is the source.

This is the drain up here. As long as the differential voltage between the gate and the source is positive and it's above the threshold value, then the MOSFET will effectively turn on. and then current can actually flow your more traditional way through from drain to source, but can also flow from source to drain as well. No problems whatsoever.

So the constant current assuming that this are in charge mode, this MOSFET here is that turned off. Then all the current will flow through the N channel. MOSFET and bingo down through your battery like that. So they're not actually using the Body Diode there, which are at first glance you might think so, but they're not because this are controlled voltage from the Vgs.

I mean they've got you know, the five volt supply for the microcontroller or whatever in there. They're going to have enough voltage in there to actually turn on this and enable this N channel mosfet. And it's going to conduct. In this case, it conducts flows in and around and charges the battery meet.

And of course, if you want to discharge the battery well, you can do that too. You just switch on, you switch off your DC to DC converter which is your constant current generator, and then you turn on both of these MOSFETs and you can drain the battery to easy. But the interesting thing about this is that regardless of the gate voltage here, you could put this right down to zero. It doesn't matter and this MOSFET is switched off.

You're still going to charge your battery because this is a constant current source. It's it. Will then use this body diet. It might might blow the crap out of the mosfet depending on how capable that body diode is, Because that's you can.

You know a lot of people do use the Body Diode for various things. That might be clever, but yeah, you got it. You got a really not you're doing in this case. Even regardless of Vgs, it will still actually charge the battery.

It's just that the voltage here at the source will actually rise by this diode drop. Let me try and explain what I'm talking about here now. I've got the voltage on the gate here. Okay, let's assume it's five volts and that's enough voltage to overcome the gate, the Vgs at threshold and switch this mosfet on when the MOSFETs on it's basically you know, zero.

Ohms. Okay, it's a short circuit, basically switches off and on site. five volts, the MOSFETs on and the body diodes effectively shorted out. So all the current flows through here like this.

So the voltage at the source pin right here. Okay, this is actually going to be exact because this is a short circuit, it's going to be exactly the same as the charge voltage on the battery. which is let's say it's one point 6 volts. Okay, due to the electrochemistry of the battery at whatever particular are current it happens to be your feet and charging at at the moment.

Now if you come along and actually switch Vgs down to zero like this, the battery will still keep charging. I should actually so I bet I should actually put that in here like this. I about will basically stay. my pen works completely constant.

Let's say it's like the eight amps that we've actually got in here. It's regardless of what VG does the battery violent is still going to stay the same. but Vgs will actually rise. instead of being the voltage directly across the battery.

it would rise by the voltage of the body diode. Okay, so the forward conduction voltage of that body diode. So it might be like naught point. six volts for example.

So it'll rise up, jump up to two point two volts. And so this point here is now two point two volts. But it doesn't matter because it's a constant current source. it's going to drive that constant current through the battery.

so it's going to stay the same. So to actually switch off the charge current, they can't just drop Vgs down to zero and try and turn off this mosfet. It's not going to work. They have to actually turn off the output of the constant current DC to DC converter generator year.

If we have a look at the thermal image here with our flow camera, we're looking at like the battery I've only had it on there for a couple of minutes. it's already at 55 degrees. you know I'm not counting for you know, emissivity and everything I don't have the exact value, but anyway, you can see it and the board over there. Very similar type of thing.

you know, 50? You know some of the diodes. I think I'm pointing at the diodes. They're seen to be the seen to be the hottest there and but yeah, she's a bit toasty I think the emissivity on that battery was a little bit off because yeah, I can hold that so it definitely wasn't it over 50 degrees So and as I showed earlier just for the triple-a battery holder here, they've just got those resistors. They were like what I am so just multiple resistors in parallel in there I think there was like six of them r1 ohms each or there abouts and then the voltage sense is coming off that.

So if you don't have the triple-a battery installed, then you know that there's no problem having you know a point to om resistor or something. In serious, you've already sense line because this is a high impedance input to your analog to digital converter, so no problems whatsoever. so they're tapping off the voltage directly from the either pad there. That's rather clever actually.

I Just remember I do a very similar thing on my microcurrent as well. By the way, I forgot this is genuine Dave CAD accept no substitute I can see some glue on that board, but nobody's home and I actually just thought that I had these resistors for the triple-a here. Back to front, but because like I'm going, where is the current sense resistor for this thing? So they know what current they're actually um, you know, charging and discharging at. But yeah, I know it's I Double check.

That's definitely right if you don't plug in the triple, A's that those resistors, the main charge current is not flowing through there. So yeah, I don't know how they're doing that Now at first I just assumed that this point the negative terminal batteries was too, just connected to ground. But I decided to go down the rabbit hole a bit further and have a look at the arrangement of all the various battery holders. Now what I found is this top part up here? Okay, is exactly the same configuration that we looked at before, but instead of going down to ground, it's actually a cascade arrangement like this now.

I've got battery hold a number I call this Led battery, hold a number one up here and then two, three and four. So I've got one, two, three and four here and the negative terminal of battery number one here. instead of going down the ground, it goes to just like the DC to DC constant current output goes into the center point of the N-channel MOSFETs Here it also goes r into the N channel MOSFET and likewise this one the negative. Channel The battery goes to the centre point once again.

So it's basically a series arrangement. so they are actually charging these things in series. Constant current here at the 8 amps goes through this N channel. mosfet turns on through the battery down here.

once again, through this channel, MOSFET is turned on through the battery, etc. etc. And if course, if you don't have the battery installed in any of them, it can detect that. And basically they cannot turn on the MOSFETs too.

You know, because you've got individual control over these. MOSFETs You can just switch. if this battery is not installed here, you can just switch on this sup MOSFET here. Boom straight down and then boom straight down.

Boom straight down and then and then this one. Here you turn on this mosfet and Bam you charge this battery here. So it's quite a clever arrangement. I Rather like it, but what? I couldn't find on the circuit I Haven't done a complete reverse engineering here, haven't gone in depth but I've had a quick look and I cannot find any way that they're actually measuring the individual our battery current.

especially the battery discharge current. Because of course in this arrangement, you can switch on the two transistors and you can discharge your battery like this. No problems whatsoever. you can discharge this one this.

but I don't see any mechanism in here. No current shunt resistor in here to actually do that. the triple-a battery. it's us separate.

It's got the sense line. Let's assume you've got the double-a Then there is no current sense resistor that I could find anyway in here. So like are they doing it Really dodgy brothers and using the on resistance of the MOSFET to get over? you know like really, you can kinda sort of do it in a rough and ready way. but that is such bad design practice.

I You know? I Don't know, but maybe it's good enough. Or then I thought ah maybe it could be a sense what's called a sense FET which actually is a regular MOSFET but actually is part of the silicon in there. It's actually got effectively an internal sensors. It's the internal current shunt resistor as part of the silicon which allows you to actually measure the current flowing through your AR and actual mosfet itself without having an external resistor.

But hey, no, that's not the case here. This particular MOSFET is just like a Joe Bloggs you know, high current and channel wah enhancement mode MOSFET So nothing fancy there at all. so it's not a sense. FET So I Don't know how they're actually measuring the discharge current of the battery, but I did find the current I Do believe the current shunt resistor that one down there.

that little one. that one in there I Think they're using that as a current shunt resistor right down the bottom so that they can. Well, that's probably most likely feeding back because of its location here. That's actually part of the Er feedback loop for the constant current generator here.

So they're actually using that to generate the constant current so that'd be tapped off and then measuring that. But yeah, individual currents I Don't know. And as for measuring the sense voltage? as I said before, you can there tap in the sense voltage directly off the terminal here which is fine, but how do you get the you know the direct like for wire measurement across the battery and I were talking a high currency so you need like a direct? Well, they've got the semester in here so there's the four thermistors. They're actually connected to the negative terminal, so are they if you feed that the output of that semester.

What like up here with this sense resistor here. If it will this drop a resistor for the triple-a batteries here, then are they actually using that into a high impedance source to actually measure the voltage? At this point? In that case, they've got their two voltage taps across each battery here, so they could actually do that. but then you've got to use your thermistor as also you've got to have it in door divider, a lower impedance arrangement so that you can actually measure the temperature. You can actually use the thermistor as you know as it was intended to UM to actually do that.

so I you know to measure the temperature, Are these switching between them? I Don't know because if you had this just this single ended sense tap voltage on here on the battery just going into a single ended analog to digital converter, then what? You've got all the losses in your shunt resistor in your MOSFETs and every or your other connections and everything else had to be horribly inaccurate. So yeah, I'm not quite sure how they do in the sense in there I Can't really figure it out on our first little reverse engineer there now. I'm actually discharging two batteries here and if you have a look at the display, you can see that we've got different values there and it does vary. so it's continually monitoring the discharge current so it must know must be able to measure and calculate the current through each of those batteries.

So yeah, they must have independent current measurement somehow. But I can't see it. So there you have it. There's a little look inside the Vada 15-minute eight and battery charger.

Can you believe it? Eight amps into a regular? well? I Believe they're pretty much regular nickel metal hydride. Although they are, they aren't ready to use that long shelf-life art type. but I Don't believe these things are actually SPECT at the full eight amps current. So you know they're just basically overcharging these things.

And as I said in my original video, number 35 either? I Can greatly doubt you're going to get the full number of charges. What is it like five hundred or something rated for these that you get if you actually charge them in the fast charge as opposed to the regular slow charger which is the recommended value to charge these nickel metal hydrides at. And it'd be interesting to know if you could actually fast charge the senior any loops as well because I can't necessarily see why not if they can do it to this. I don't think there's any magic secret source in this so I think you can probably do it to any loops as well.

but I don't know of any data out there of you know people or products actually really fast charging and say at 8 amps they send you any loop. so if you've got any data or stuff on that, then yeah, please leave it in the comments. But once again, if you did overcharge the send your any loops and you know you're using a charge like this has got the product proper protections. it's got over temperature.

it's got negative Delta V it's got. You know it's got all the protections possible so that you don't actually so these things don't actually catch on fire when you charge them at a dance cos we remember nickel metal hydride batteries are exothermic so if you didn't actually temperature sense them and cut them off when they were fully charged I can run away on you and well I don't want to know what would happen. hmm so I don't have any seor any loops to our hand I've been using these vital ones. they seem to work really well I haven't uh you know use like the 500 recharges on them to actually over the years to actually see if you know the battery life drops.

Number cycles are drops on them. The senior ones would drop what are they rated for like 1500 charges. You'd never get that if you I don't think if you're charging them eight amps. The datasheet exists here for a reason.

You know it's there's a reason why it says you know, only charge it two amps. there. it is. So yeah, like disobey that at your own risk and that's what Varta are doing.

But this isn't a genuine official Varta charger, so you know they. I Guess they have to stand by it. But as it stands, the circuit is a good example of a real, minimalistic and rather clever implementation to get individual work, soul charging, and discharging using these. MOSFETs So I'd love to do a better reverse engineering and if anyone actually already has knows of a schematic or anyone who's done any reverse engineering on this, then please let me know at the moment I don't have time I just want to get this video uploaded.

so I might have a second shot at this. Might have another look around here. Do what? see what's what and how they're doing, the individual cell discharge currents and also the voltage sensing as well. because I I think it's all a bit, you know I I expected individual charge You know, circuits for each one and proper differential voltage sensing and all that and it just seems to be a bit rough and ready.

but I you know they're doing, they're getting away with it and you know Vy2 know what they're doing so you know they've got to stand behind their product. And the charger works. I've been using it for years or at least the previous generation one. but yeah I don't know Evernote won't catch on fire yet but my fingers crossed so you got a wonder.

Didn't mark it in like I Come up with this all. we'd love to have a 15 minute charge. a Leo Sonia is not doing that. Let's come up with that.

You know, really? SuperDuper Fast. Four times faster than what Seor can do. Let's do that in engineering. Go well, you know I don't know.

the bloody battery chemistry's me. I'm not going to get the same life out of it. It's a bit dodgy, but oh yeah, we can come up with something and it's got to be cheap too, so you know they've implemented it cheaply. And yeah, okay, it kind of yeah, kind of sort of works.

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