Inside the Turnigy Accucell 6 Lithium Ion/Polymer/Iron Phosphate 6A Battery Charger.
http://www.hobbyking.com/hobbyking/store/__7028__Turnigy_Accucel_6_50W_6A_Balancer_Charger_w_accessories.html
And a look at the JBC CD-2BB series soldering iron:
http://www.amazon.com/gp/product/B008LZ30Y4/ref=as_li_ss_tl?ie=UTF8&camp=1789&creative=390957&creativeASIN=B008LZ30Y4&linkCode=as2&tag=ee04-20
Schematic: http://www.rcgroups.com/forums/showthread.php?t=1362933
MOSFETs:
MT8103A http://www.mtsemi.com/_control/upload_file/MT8103A.pdf
FDS6680 http://www.fairchildsemi.com/ds/FD/FDS6680.pdf
Forum Topic: http://www.eevblog.com/forum/blog/eevblog-397-turnigy-accucel-6-charger-teardown/'>http://www.eevblog.com/forum/blog/eevblog-397-turnigy-accucel-6-charger-teardown/
Dummy Load Video: http://www.youtube.com/watch?v=8xX2SVcItOA
Battery Capacity Tutorial: http://www.youtube.com/watch?v=R8hTQXqURB4
Battery Charging Tutorial: http://www.youtube.com/watch?v=A6mKd5_-abk
Battery Discharge Testing: http://www.youtube.com/watch?v=ln8Mlz4NsW8
EEVblog Main Web Site:
http://www.eevblog.com
EEVblog Amazon Store:
http://astore.amazon.com/eevblogstore-20
Donations:
http://www.eevblog.com/donations/
Projects:
http://www.eevblog.com/projects/
Electronics Info Wiki:
http://www.eevblog.com/wiki/
http://www.hobbyking.com/hobbyking/store/__7028__Turnigy_Accucel_6_50W_6A_Balancer_Charger_w_accessories.html
And a look at the JBC CD-2BB series soldering iron:
http://www.amazon.com/gp/product/B008LZ30Y4/ref=as_li_ss_tl?ie=UTF8&camp=1789&creative=390957&creativeASIN=B008LZ30Y4&linkCode=as2&tag=ee04-20
Schematic: http://www.rcgroups.com/forums/showthread.php?t=1362933
MOSFETs:
MT8103A http://www.mtsemi.com/_control/upload_file/MT8103A.pdf
FDS6680 http://www.fairchildsemi.com/ds/FD/FDS6680.pdf
Forum Topic: http://www.eevblog.com/forum/blog/eevblog-397-turnigy-accucel-6-charger-teardown/'>http://www.eevblog.com/forum/blog/eevblog-397-turnigy-accucel-6-charger-teardown/
Dummy Load Video: http://www.youtube.com/watch?v=8xX2SVcItOA
Battery Capacity Tutorial: http://www.youtube.com/watch?v=R8hTQXqURB4
Battery Charging Tutorial: http://www.youtube.com/watch?v=A6mKd5_-abk
Battery Discharge Testing: http://www.youtube.com/watch?v=ln8Mlz4NsW8
EEVblog Main Web Site:
http://www.eevblog.com
EEVblog Amazon Store:
http://astore.amazon.com/eevblogstore-20
Donations:
http://www.eevblog.com/donations/
Projects:
http://www.eevblog.com/projects/
Electronics Info Wiki:
http://www.eevblog.com/wiki/
Hi welcome to Tear Down Tuesday I Had a couple of people ask after a previous video if I can do a tear down on this turnery Acurel 6 because you saw me use this in a Lithium Polymer battery discharge video I did where I discharged I got the discharge curve of a 5 amp hour uh LiPo battery from Hobby King and I also mentioned that this thing is available from Hobby King as well for the amazing ly low price folks. amazingly low price of $23 us. Unbelievable! Um, this is for a 5 amp uh charge uh, charger 1 amp discharge and uh, it supports all the different types of batteries. Three different types of Lithium nickel metal hydride, Nikad, and lead acid as well and it's got LCD user interface, all sorts of stuff.
It's got a temp sensor interface with an optional Ser well a Serial data output as well. It's got controls, it's got fan, it's got a buzzer and it's uh, supports balance uh, charging and balance discharging of all the cells with all the different types. So you can do single cell you know uh, two cell, three cell, four and five and so on. and it's a really amazing little beast for the price $23 Got to be kidding me! Um, even from the Australian uh warehouse for Hobby King it's only $29 or something.
so absolutely amazing. Anyway, I had a few people ask if we could tear it down and have a look. It could be interesting. As you can see, it's in a rather nice uh alloy case here.
I Rather like it, it's in two. Hales It looks like the front and end plates just uh, pop off with the four screws there and uh, that's you know there's not much uh to this thing at all. It is quite small and Compact and as I said, it is actually um, you know 5 amp charge capability and 1 amp discharge as well. Now uh sorry Max charge six there it is 6 amps uh charge and 1 amp discharge and uh, it you know for this little compact size really is quite neat and by all accounts, um, it is a very popular unit and works well.
So let's crack open these uh end panels and uh, see what's inside. As I said, this thing is very popular with the uh remote control the massive remote control community and there is, uh, quite a lot of um, you know, reverse engineering done on this I think people have done new firmware and stuff I'm not sure about reverse engineering, but they've I believe like they've done new firmware and there's people hacking the thing to make it more accurate and uh, stuff like that. So I mean for the price, you know it's ah, it's actually impossible to beat and apparently it is based on the same model um that shares like different brands. they're a very similar um, but they you know they might have slight differences in them.
but apparently the circuitry is uh, almost identical between these units. So um, hopefully this will apply to the other ones as well. and apparently it's quite well made. We'll find that out in a second.
Let's whip this sucker apart and what? I'm Oh, there we go. What I'm interested in is the discharge capability, which we'll have a look at. Yep, there we go. Plates just pop off and yep. Tada there we go. Doesn't that look neat? Look at that that one. Actually that the build quality looks very, very good. I Like it at first glance.
Now the construction of it really is quite neat. quite compact. They've got the LCD that's soldered directly in there. It's not I don't think that's socketed.
no, that's soldered directly in there. We've got a uh vertical Riser board here for the um, uh balance balance connectors on the side there. It looks like we've got a whole bunch of load resistors there for the balance channels 1, 2, 3, 4, five, six of them there. So uh, apparently you know that you would have one of those channels for each uh cell of course.
Um, so that you could, um, dischar charge the well load balance each particular uh cells. So a battery like this? uh, matching turnery? uh, three cell? um RC battery that I've got for my Quadcopter it. You know, a very high discharge capacity. Of course you know 35 to 45 uh C rating.
So you know, absolutely you know huge amount of discharg current. And there's the main Um battery terminals of course huge chunky things. but it also has these balance leads coming out out which Um allows it to detect across each individual cell. So this is a four pin one of course you got ground and then the th the voltage across each individual cell in there.
So that allows this thing to um put a load across each cell and then balance out this battery because it's very important when you got these massive discharge rate uh batteries that you that these cells are balanced in there. Otherwise, um, one cell can die prematurely and that's going to bring down your pack. and well these things can. You know the energy, uh, density and these things.
They can explode, catch on fire, and do all sorts of weird and horrible things which you don't want to happen. So that's why it has all these balance inputs and a different connector for um, the number of different cell types there and it looks like we've got some DC to DC converter. Pretty beefy stuff happening around here. You need that of course to get the Um higher voltage voles than the 12v input.
Of course it's just 12vs DC input, but it's capable of Um packs which are actually more than that. So it's going to have a boost converter in there to generate the higher voltages required. Couple of user interface push buttons. We've got our buzzer got little fan it looks like it's probably um, under PC control there? I Don't think it goes? uh, micro? uh, control there.
It doesn't go all the time and uh, there's got to be some extra big feds. Tada There we go. Some extra big feds under the bottom. there.
That one is, uh, you can see the seal pad under there isolating that from the uh thing. They' got some white heat sink compound under there, so that'll be a mosfet under there as it got. And yeah, it's got another one. It's hard to see under there, but it's got another one tucked up right under there there, so it looks like they're wedged between there based on that standoffs under the bottom of the board. So these screws here will be, uh, holding down and pressing those uh To220 packages against the base. and the Bas is of course used as the heat sink and under the LCD Here we're going to have the micro controller of course, and then probably some more analog stuff, some Op amps, and a whole bunch more resistors. cuz you're going to need a little bit more than, uh, what's shown on the outside of this here, so there'll be a bit more circuitry under there. and uh, you'll notice that, of course, the, um, the balance resistors here.
If you're wondering why there's so many of them, they're actually paralleled up. so they've just got uh, um, 0805 resistors there all in. they've got what 246 in parallel there just to get extra power dissipation. And if we have a look at the 4 mm banana Jacks here you can see that they're just uh, solded directly onto the pad there.
I Don't particularly like that. um at all, but uh, you know I guess it's good enough. Um, not sure if there's any reports of them having, uh, broken off, but anyway. um, it will do the job.
Um, you can get ones that are actually PCB Mount So they actually have pins which go through the board, but I guess they, uh, cost a fair bit more. We got a couple of load resistors here. um, not sure what they're doing at the moment. There's two of them.
One will be the uh discharge with the discharge uh fit of course, but interestingly it's in the negative. Uh, yeah, we've got one in the negative lead there. so that'll be a mosfet, which we'll take a look at. dead dead giveaway on the pin out there.
You can tell because the I can't see the number at the moment, but you can tell it's a mosfet because it's a three pin device. We' got all four pins connected in parallel. there another three over there and the one pin there, which will be the Gate Drive and that is a load resistor. We've got uh 0.051 HS there.
Interestingly, they've missed that solder joint there, but I'm trying to budge that it's obviously solded on the other side. so not a problem. and it looks like might have a 3 amp Poly switch there. by the looks of it.
hr30 I'm assuming that's a 3 amp Poly switch. Not actually sure what that's uh doing there. it's AC It's near the Uh balance uh circuitry. It's nowhere down near the uh battery connectors down here like it's not, uh, you know, in line with um, the battery terminals down here.
so it's got something to do with the balance circuits. and that n Channel mosfet down in there is an Fds 6680 or a variant uh thereof, which is traditionally from Fairchild and uh, as I said, it's got a 51 milliohm um Source resistor down the bottom and it's rated at 11 1/2 amp, 30 Vol 10 mm nominal on Resistance and it looks like we've got an LM 2904 uh Jeel Op Amp down in there once again. Um, I'm not sure what brand that is just a generic brand and down in here. as part of that DC Todc converter circuit down here, we've got a Uh P Channel Mosfet Mt 8103 and once again, that's a similar order to the other one uh 13 amps, 30 volts nominal 10 MMS on Resistance and up near the DC input jack, we've got another engine Channel Mosfet the 6680 that we, uh saw on the battery output. And to see anything more here, we're going to have to crack this thing open. so I don't I doesn't look like there's any circuitry on the bottom of this thing. So I think it's all single sided load apart from the mosfets on the bottom of course. Oh, this will, uh, require that I Oh no, there we go.
Tada No, nothing on the bottom except the mosfets. Now there's one thing I'm not hugely keen on here. the ground from the DC input jack, which of course needs to be uh High current is just going through one pad over here one plated pad and that's it. Granted, it is quite, uh, quite large.
but uh, that's all that it's going through. but it looks like they have designed this for like uh, flying wires coming off here or something. So maybe there's another model that has um wires coming out cuz that's not really a footprint for some sort of connector. Um I think it's just for, like, bare wires.
and I don't mind the board. uh, interlocking they've got here. You can see that the uh, there's been a routed out slot in that vertical Riser board. This is a common technique for joining two boards together at right angles.
like that. sold it on, uh, both sides like that. Of course, because all of the strain on the this vertical Riser board when you plug those in, all that strain is being put on those solder joints. So this is a fairly time oned rigid method of Uh joining and interlocking two boards together like that and you can see this uh High current uh Trace over here and the heavy uh via stitching going from one point to the other because they've obviously got traces on the other side running across here.
and they had to get, uh, all the current from the DC to DC converter over in this section over here. Um, to the Uh output connector over here. So um, they've used you know, 12 uh, V's in there and the rule of thumb is, typically, you know, um, half an amp nominal per via like that and the two caps on the board here. um, Swc brand.
They're not a name brand, but I don't think they're particularly uh known as anything, uh, atrocious. Yeah, nothing going on there at all, but you wouldn't expect a um, you know, a nichon or something like that in a $23 charger. You got to be kidding me. this one is actually uh, sastic.
Down there we go, we got some blank black Gunk under there holding that one down, so that's a nice touch. This one here isn't held down at all and along the top here, I'm sensing a microcontroller ISP interface and I just noticed that there's a bit of alignment issue with the couple of the resistors down here, but uh, no big deal. I mean generally the Uh soldering. The Reflow soldering quality on this thing is uh, first class. Now to desolder this LCD I Thought it' be a nice opportunity to try out my new JBC CD series. I in here and you'll see a review of this. Never used it before, never even powered it on but they did Supply it with a nice looking wedge tip which I should be able to get in there and heat up those and lift off that LCD nicely. So yeah, grown.
It's a button interface with a um LCD uh display and a non- removable stand which I'm not particularly uh keen on. but let's uh Power this thing up and uh, see what we get Tada JBC Tools program version Oh God when you solder in IR has to have a firmware revision number tool is in the stand. There we go. it's it.
Auto detects, look at that and it heats up incredibly quickly. That is like a amazing. It's the first time I've ever powered up this thing. First time powered up that tip.
You can see the solder actually flowing from one end of the tip to the other, hopefully there. Wow, that was near instant. Really, absolutely incredible. Looks like it's got a bar graph on there which I assume will go up as you, um, apply like a Dees uh pole Peak Power I'm assuming I don't know sorry I haven't uh, this is not a review I have not uh, investigated the details on this at all but I'm assuming that that power will uh, go up to like 100% or will uh Peak up when you um, apply power to it.
So it's got the selected temperature there and the I'm presuming the actual temperature H Let's give it a go look at that. it goes to sleep as you put it on the stand. Nice, You can see the actual temperature is uh, down to 230 there. so it looks like it uh, goes to sleep at 220.
Well maybe it's cooling down. Maybe it's cooling down if I well lift it off Bang Yeah it goes up to 99% and bang. It's instantly almost instantly back at 350. Very nice indeed.
So let's leave it on 350 and oh, heats up all those pins at once. Absolutely beautiful. Ah, very nice. I'm impressed.
So let's attempt to desolder this thing. I'm going to go on the uh the pins on the board. they're just lifting out if I can get in there to all of them. there you go That popped out without too much uh grief.
although I did, uh, take out some of the through hole plate in there. oops but that's common with these Square post ones. If you don't get the holes the right size in the board, you can uh, risk taking out the um, uh, you know the pads in there I mean the safer way would have been to get in there and cut all the pins off and then you could remove each pin one by one and you could do it quite nicely. but that worked. A treat that JBC iron Pretty darn good I'm impressed, but you'd want to be for the price unfortunately. uh, that didn't work out as intended I was a bit foolish there. I should have uh, chopped off the pins along there and sacrificed the LCD cuz what's happened is it looks like some of those holes are, uh, were quite small and we lifted a whole bunch of pads off there. I mean this JBC iron was so, uh, you know was applying so much uh Power to all those pins and it felt good as I was lifting the thing off.
but no, What fail should have sacrifice the LCD instead. Idiot. It's a real bummer about those pads in there, but they can be uh repaired. I was uh, hoping the reason I took those out is I was hoping to put a socket in there so that I could, um, then plug the LCD in and out for uh, hacking development.
Still doable, just ugly and what we have there. No surprises. an At Mega 32A So Au version and what else have we got around here? We've got a Uh Hcf 4051 so we' got an analog switch there and uh, what do we got up here? We've got an LM M 324 Classic Lm324. Let's have a look at this other one.
let's have a look. Oh, it's another 29 LM 2904 dual op amp. So we got a couple of LM 294s and LM 393 comparator and around the DC to DC converter. There we've got another 66 80 um N Channel mosfet there.
so there's no controller at all for the DC to DC converter, so clearly they're uh, doing that in the micro by the looks of it and down under there we've got an Irfz 44n and that looks like it's the main Uh discharge mosfet. and the reason I know that's the discharge mosfet is cuz there's the drain there connected directly through the positive terminal via a little wimpy Trace there cuz this is only a 1 amp discharge. Uh, of course it's not. Uh, it's not a huge discharge current and then the uh Source if you look here goes down to Tada that resistor down there which is also tapped off for the voltage.
read that'll probably go over to one of the ADC pins. Um, you know, probably through some dividers or some amp or something through to the uh, um, analog to digital converter in the At Mega and then it goes to ground through this resistor here. And if you're familiar with my uh previous videos on the uh, dummy do-it-yourself dummy load which I'll uh Link in, then this is a classic um n Channel mosfet uh, dummy load resist circuit. And that's particularly what I'm interested in here because we have for what 23 bucks? um, A Effectively, what should be if you can just hack the firmware in this thing.
it's just an At Mega It's got an LCD It's got the buttons. It's got the case which is acting as a heat sink. It's a it could be a relatively, um, nice little, um, not particularly high power. Uh, dummy load.
You could program the thing for constant current uh, constant uh Power or constant resistance H Neat. So clearly this other uh mosfet here is uh, the one with this uh 50 1 mli ohm Source resistor here is the one that's used for the uh constant current charging. You can tell the huge big Fat tracers on there and it looks like we got pairs of uh transistors here to switch in the balance uh, loads across here. one for cuz there's six balance channels there with six balance loads as well. So um, looks like it's a some sort of dual transistor configuration controlled via the micro almost directly by the looks of it. and the other To220 device is a 7805. Why they had to, uh, heat sink that? I'm not entirely sure now I Was going to do a bit of reverse engineering on this circuit, but I thought I'd Uh, check first to see if somebody's already done it and uh I think that they have I'm not sure if it's an original, uh, schematic or whether or not it's um, uh yeah. actually reversed engineered and they've drawn it uh, in CAD but it's not for exactly the same one.
It's for the Bc6 uh charger which is a almost identical uh charger not quite, and the circuitry does seem to be almost, uh, identical. There's a few um, uh, a few devices that are different, but the actual topology and the circuit itself appears to be pretty close to identical to this turnery. um Acel 6. Now let's start by taking a look at the main Uh DC Todc converter circuitry here, and as you can see, it's a classic Buck Boost topology.
I've circled the three components for the Uh Buck part of it a P Channel mosfet, the doode down there, and the main inductor which you uh see on the board. So if we have a look at the main board down here, we're going to see there is our P Channel mosfit. There's our diode going to ground just there, that's ground and there's our inductor going through to the Boost part of the circuit here. and of course the Boost classic topology.
We've got our inductor first, we've got our Uh N Channel mosfet which is that one there and then we have our output diode there and our big filter cap there it is. They got a little little snubber on there as well and uh, that is Um controlled by the Dual comparator here the LM Uh 393 and it basically takes the output from the error, the error. amplifier output here I've circled that up there and that comes from the Uh this sense amplifier on the Uh lows side um N Channel Mosfet which detects the charge current there so that's working as the error amplifier and that's and they can read that off as well. That's going off to the ADC Um as well and it actually tells you there I mean if I'm not sure if you can see that in there, but it tells you it goes off to ADC Channel through this.
So This schematic is uh, quite detailed and it tells you the Um actual ADC channel. So the error amplifier comes in there and the actual set voltage is controlled via a Pwm presumably a 10bit Uh one from the Um Atmail microcontroller. and they actually tell you which one it uses. it's OC 1B there there and that sets the Uh voltage. Now it looks like that they've got a Um like a switch off. Here there's a a control signal which comes in here and that just Uh pulls the output of the Pwm low. Anyway, this Uh control signal looks like it just disables that output, pulls it low there, and also it goes around to here and pulls that one low as well. Now, the LM 393 isn't Um able to drive the Uh.
Well, they haven't made it drive the Uh Mosfets directly because it's just a totem pole output. So they got the pull-up resistor there and they got the two transistors here which form the totem pole uh driver with a 10 ohm series resistor to drive the Gate of the large current mosfets there. Oc1 A that is, uh, the constant discharge one which is also up here. and here is a the part of the circuit that I'm uh, particularly interested in because this could be a this well essentially is a Um a dummy load just like you've seen in my previous videos.
Here there's our N Channel mosfet. It's the Irfz44 which of course is the main Uh one on the back of the board. there, the main heat sunk one there. And then we've got our current sense resistor .5 ohms down there and uh, that that is a nice little constant current dummy load or depends on the software, you could do constant power, constant resistance, or whatever so it wouldn't be too hard at all to uh hack this thing into a nice little uh dummy load.
Not particularly huge power unless you wanted to. uh beef Uh, the components and the heat sinking up a bit, but certainly are very usable and they're tapping the voltage off here amplifying that and that's going off to ADC Channel two there. Now here's our positive and negative battery input here and you can see that battery bat plus bat minus and that we've got a differential uh, tap on that via this. uh via these two fixed dividers into the Um LM 2904 Opamp here.
Now you may notice that there's no feedback there, so you may wonder what's it doing. Is it acting as a comparator or something? Well, no. The feedback path is actually the Um output here, through the Um charging current mosfet, through the current voltage tap here, and then through the Opamp through the error amplifier and then that error signal is fed back into down here, which then Uh mixes in with your Um Pwm set voltage to control your switching mosfet for which then goes directly to the battery output. So that's your feedback system there with with that error amplifier.
And once again, we've got like a little safety Uh circuit here. This Um Npn transistor, just regardless of what's happening, just pulls the Uh gate that mosfet low and just switches off the whole thing. and we saw a similar thing down here. Where there it is there we go that just uh, shorts out the Pwm Um signals there and uh, just switches it all off and this whole thing is rather clever. I Like it. it's all sort of. You know, the buck boost Uh converter here is Um integrated with the entire Uh feedback system for the con, constant current and constant voltage charging modes. It really is quite nice with the Amp here and the Um current set um Fet down there with the current Sens resistor and tapping off it.
It really is quite neat. I like it. It's very clever. And here's our DC input jack here.
and they've got a Uh reverse protection mosfet in there. They didn't like put a diode in series or something it to dissipate too much power. so they decide to put a mosfet in there. So if you plug in the Uh input voltage backwards which Uh could easily happen on these types of things considering that they're used in all sorts of weird and wonderful scenarios out in the field, that's just some reverse protection.
Although there's more than one way to skin a cat there. An easier way would have been a P Channel Moss Fed Up on the Uh high side, but they just decided to go for the Uh N Channel mosfet, the 4468, which is Uh used elsewhere, and just the voltage divider. So positive input there turns on the gate and switches the ground so they're actually disconnecting the ground in there and you'll notice that the main electrolytic filter cap there is after the switching transistor. So if you apply negative voltage, it's not going to blow up your electrolytic cap when it's backwards and you can see the balance uh circuit here.
and uh, just as I suspected, right at the start, we've got a Darlington Uh configuration here, and then another driver transistor driven directly from the from a pin on the micro there. so there's our six load resistors in parallel. Looks like they're 120 ohms, six of them in parallel and that this is drawn a bit. Um, upside down.
Really, they've got um, battery negative at the Uh top and then they've got the balance one pin and then the next one goes from the balance one pin to the balance two pin and so forth. So um, as you can, you know it would be like that we would have a cell like that and then our next cell would be like, and that's if that's our ground there. Then our next, um, almost drew that back to front. It's a bit confusing here, but then that's our next cell and then goes in here and then our next cell like that and so forth.
and that just Taps off. Um, that each individual cell like that and oh, there we go. Looks something like that and that just Taps off each one of those cells and that allows them to allows the software to just to balance the uh, put a load across each cell and then balance it out like that. So it's rather neat.
So if you flip it around the other way, you'll get an idea. There's the positive of each battery cuz of course these uh, multi cell battery packs like this one. This one's a three cell pack. There it is three cell 11.1 volts nominal and that will contain these three cells in series. And if they're not balanced correctly, one of them can, uh, die and your battery is going to have a very short life or could uh, end quite violently. And then we've just got some Uh buffers here, tapping off each in each particular uh balance cell. Like that and they go directly. um, well, sorry I Was about to say directly into the ADC they don't They go down to the 4051 marks down here and there's some more dividers down here as well and they go into all the channels of the 4051 and then the Uh micro pins select which channel it wants to, uh which cell voltage it wants to measure and that goes through to the main ADC via a low pass filter.
And this schematic here shows a Um USB interface uh, serial, uh chip here which um, isn't Um included in this design so that must be uh, something to do with a different model. But apart from that, this Uh schematic does look like it is pretty much um, the exact Uh schematic of the Turnery Acel one that we've got here. I Haven't really, uh, found any uh errors on it yet? I Mean there might you know, might be component, uh, value differences, and uh, stuff like that, component types. but the Uh General topology looks to be absolutely identical.
So there you have it, that was rather interesting. That's the Turnery Acurel 6 charger and um I don't really recommend uh, you get one and sort of hack its charging capabilities. It's already uh, you know very well. uh, suited to that and by all accounts, and excellent uh charger.
So I highly recommend you get one just as a general purpose charger and at 20, uh, $3 you've got to be kidding me. got to pay postage on top of that. But gez thing, it's absolutely dirt cheap and it's uh, designed and built quite well. I Rather like it.
but I find it interesting that it should be easy to uh hack this thing to, uh, write your own firmware and turn it into a relatively, um, good little um, dummy load. constant current, constant power, constant resistance, dummy load, and uh, you know it's not going to dissipate a huge amount of uh Power but it certainly usable and you can expand it. You can, that, you know, change the resistor down here. you can, uh, heat sink that mount it on the bottom, press against the bottom of the case.
you can add a larger heat sink on the bottom of the case or something like that, and uh, but you know, so it might make the basis of a nice little do it yourself hacked dummy load. Give it a try, you might see some uh, future videos on it. Maybe I'll have a go at it myself. That was, uh, the intention anyway.
so I hope you enjoyed that. If you want to discuss it, um, jump on over to the Eev blog. Forum that's the place to uh do it and remember if you like tear down Tuesday Please give it a big thumbs up. Catch you next time.
That thought hole is not for wires itโs for a xt60 connector
You are just alway spot on. Thanks for sharing.
That ic looked like an oscillating timer like 555.
BUT WTF DOES MURIEL THINK ABOUT IT!? ๐
great charger, ive had mine 5 years and its still going strong.
It is good to see that it is not only me who accidentally destroys pcb pads whilst desoldering! Recently, I 've some succes using an clothes iron as pre-heater. Yes, cutting the pins is a good idea too, but that's not always an option.
Old video but perfect viewing time for me, about to buy something very similar to this.
Love your tear downs, especially the way you explain the circuit diagrams. Thank you Dave, your the ducks nuts down under!
Would really like to see more chargers being tested. With the ebike movement it's a growing need for good cheap and fast chargers like this.
Eight years on and this video is still useful, I managed to find part number for a blown chip thanks to Dave…
BTW, open source firmware is available for this charger as mentioned in posts below…
Ohh mate, solo daengerouuss!! ๐ฒ
I've been using this charger quite intense …. Now the mystery how the balanced charging work seems solved ..
I had been thinking each cell has an isolated DC-DC boost converter as cell charger … LOL …
I have the exact same one. Had it on LiPo for the longest time. Just today, I fired it up to do some LiPos but the display now reads LiFe. ??? What happened? Despite the display no longer reading LiPO, is it safe to do those with the LiFe showing?
what is 8 leg ic near + – mine burnt
I am getting the error:
Invalid voltage
Cell error
First I tested the battery, but it was ok.
And after it I soldered the balancer connectors and it worked!
But now it isn't working anymore.
Any idea?
Hi,my Turnigy accucell 6 has a problem "Reverse polarity".Does anyone know what to do?Damaged mosfet?Please help me someone.Thanks
Just for once you could have used a Weller VP801EC
@EEVblog
I just wanted to let you know that this old video of yours is very exciting to me and still relevant today. The modern chargers are probably still the same.
I've just brought one of these Accucell 6 Chargers since I'm getting quite a collection of different batteries (Li-Ion, Pb, Li-Po etc) and had nothing to charge them all with. For ยฃ20 it's worth the money. It's got quite a few features and it does what it says on the tin. However one thing I wont be buying again are batteries from off the Internet or more specifically, eBay (China Bay). I purchased TWO sealed lead acid batteries from eBay this year. One was a 12V 7aH and the other a 6V 10A and both are crap. The 12V SLA Battery would charge to 13.8V and then crash down to 10.5V as soon as it came off the charger and the 6V SLA battery charges from 6.5V to 7.2V in 23 seconds according to my charger and as soon as the battery comes off the charger, it's back down to 6.5V again. Absolute crap. And the same goes for 18650 batteries… I brought 2 of these 18650 Batteries from China Bay and guess what – they were fakes. I'll stick to getting my batteries from a trusted local Burglar Alarm Suppliers.
I love that you know the proper meaning of RC.
It's REMOTE control guys! NOT RADIO Control!
There are other ways of controlling these models, like infrared for example, which is not radio based, but it is remote.
Same IMAX inside just builded from same factory in CHN and changing face