Author Topic: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack  (Read 105089 times)

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Offline LesoleeTopic starter

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #25 on: February 03, 2020, 03:53:42 pm »
I applaud your hard work on this. I and some family members have Dysons and it's only a matter of time before the batteries start failing so I'm hoping you'll succeed!
Thank you. To be fair I had run out of ideas when I posted the first message. Various encouragements have brought about new ideas to try. I am still in the position of having no further ideas  |O

If Capt Bullshot is right, and an internal variable has been flashed, that seems problematic. I suspect a device with internal flash may well be itself programmable, so that a far UV source might clear the flash variable and the program at the same time.  :'(
 

Offline capt bullshot

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #26 on: February 03, 2020, 04:11:23 pm »
I'm astonished by your effort to revive this battery pack.
For me it is not just one, but potentially thousands. The landfill waste of a nearly working pack is horrific.
I absolutely agree. It's a horrible waste of resources - some year or two ago, I recovered about 300 18650 cells from unused but for some reason discarded (shitty) power banks - my plan is to build another "large" battery of them for my home low voltage solar power supply system: http://wunderkis.de/pvbat/index.html . The cells are no-name chinese 2000mAh (usable 1500mAh averaged), so the final battery should be good for more than 1kWh. Among other issues (including a temporary lack of motivation), I'm still searching for a "fireproof" place to put the final battery into. Already made a lot of 9P packs, each nine of them will be paralleled in a total 81P / 4S configuration, so the charge/discharge current on the individual cell will be quite low (less than 15A current for the whole battery is planned). This way one can get quite an amount of capacity of these rather shitty cells.
« Last Edit: February 03, 2020, 04:13:15 pm by capt bullshot »
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Offline schmitt trigger

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #27 on: February 05, 2020, 03:12:14 pm »
My post #3 proved to be an Omen.
My wife just called, telling me that my V6 is quitting after a few seconds of operation.

And indeed...although the replacement packs on Amazon are not that expensive, the bigger deal is the E-waste. I definitively will NOT dispose in the trash, but plan on looking for a recycle center.
Just hope that the recycle center does indeed recycle it properly.

Most likely it will end up in one of those African countries where they "recycle" the E-waste under terrible environmental conditions.

EDIT: Rather than hijack this thread, I will open another one related to replacement batteries. This time on E-bikes.
« Last Edit: February 05, 2020, 03:15:39 pm by schmitt trigger »
 

Offline wilfred

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #28 on: November 05, 2020, 06:24:50 am »
I have a need of a replacement battery for a Dyson V6. As far as I can determine it is Part number: 967810-21 on the Dyson Australia website and appears to be $79 with free shipping. I assume it will be about the original capacity. I'm not too bothered by the price since I got the device free.

Checking on Ebay there seem to be endless selections of 4000mAh batteries with brand name cells. Of course I and I imagine no-one else will open one up to verify this and I doubt they are either 4000mAh or brand name cells for about 1/2 the price of the Dyson genuine battery.

Has anyone had experience with these non-genuine batteries? I've done a bit of searching but haven't found much except for a NYtimes consumer article which wasn't complimentary.

 

Offline DavidAlfa

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #29 on: November 08, 2020, 06:18:22 pm »
I guess those BMS are made in way that they will lock up if you try to remove the batteries.
More planned obsolescence, and engineering to block repairing.
Tried few times with laptop batteries, once you desolder the battery pack, it's over.
I'm 100% sure that the thing sets a bit on its eeprom on first boot. Then, it never powers off.
The voltage should never go down for the bms, when the battery goes flat it just cuts the output, but there's plenty of juice left for powering a micro-amp bms.
So in the case you replace the cells..Bang! It knows the supply was removed and won't work again.

In not "high end" devices, I was able to replace the cells successfully.
Last week I did it again with a Lidl impact drill.
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Offline najrao

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #30 on: October 06, 2021, 03:27:37 am »
I want to revive interest in this oldish post.

Having read this over again, I was spurred to acquire six of these Dyson batteries to see if there can be a salvage. Flea market, but still moderately pricy.

One decapped is exactly the same as Lesolee's, and tests out the same, i.e., 32 red flashes (+ one blue sometimes). There is never any output, nor any charging current at input. The cells were only partially charged, and somewhat unbalanced; I rebalanced them and charged up fully. A partial discharge test showed cells to be still good.

I disembowelled a second, bigger 7S 3.6Ah (picture), after some serious spudger work. Somewhat different BMS pcb, no reed relay or other switch here. The control chip can be read under powerful light, and is BQ76930. Seems cell equalizer is fitted and works, all seven cells showed 4.065V exactly. There is no output or input, and no led blink at all. Sad.

If forum wisdom cannot crack this, I hope to simply replace the entire BMS by a generic unit, and recover the high value battery. What issues in selecting?

Do chip in if you will, please. Thank you all.
 
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Offline SilverSolder

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #31 on: October 07, 2021, 01:46:47 pm »

This thread has reinforced my conviction that corded appliances still have a place in my life!  :D
 
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Offline scootley

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #32 on: December 14, 2021, 03:03:07 am »
(Hopefully this isn't too off topic for this thread.  Will re-post in a new thread if so)

There is a video online (see below) showing the process (for a model DC30 vac) of removing the factory cells from the battery and soldering on some common RC-style lipo battery connectors (one for power and one for balancing), and then using such a commonly available battery, as long as (presumably) it has the same number of cells (in series) and same nominal voltage per cell.  I wouldn't think the cell physical size (18650 vs 21700, etc) or capacity in MAH matters too much, right?

And as far as I can see, the Dyson stock charger would work too, right?  The video creator seems to say in comments that he doesn't use it because his other charger is faster.
This seems to be a great option to avoid things like:
1) Having to pay for expensive Dyson OEM batteries
2) The fact that Dyson OEM batteries are discontinued X years after the vac is
3) Dealing with low quality BMS circuits in cheap replacement batteries
4) Dealing with low quality cells in cheap replacement batteries (since it seems easy to find high quality versions of these RC batteries)
5) Making it very easy to replace the battery without any spot welding, etc

Anything critical related to safety or functionality that I am overlooking?  I'm assuming the Dyson BMS will handle all of its regular functionality with such a battery pack attached as if those cells were just like the originals and spot welded to the nickel tabs.  Maybe just need to pick a pack that can handle the same sustained amperage, but I believe that most can and I suppose one could guess based on the C rating.  And choose connectors/wires with the correct amp rating.

I also see a there's an adapter for a Makita tool battery to fit it to Dyson V6, but obviously this won't charge the battery and I have a feeling that it does not appropriately handle low-voltage protection.  They don't make one for V7, which is what I have.

Edit: One issue may be that I believe the stock battery has a temperature sensor and it may be a bit tricky to get that positioned well with the lipo pack.  Or perhaps it could be eliminated, but that probably carries some risk.

Edit 2: Oh and there is a reed switch in the stock battery, right?  Probably should be easy to deal with.


« Last Edit: December 14, 2021, 03:31:52 am by scootley »
 
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Offline najrao

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #33 on: December 14, 2021, 04:51:30 am »
Very interesting, thanks.
Later Dyson models have much more difficult bms's. They seem to lock up even with perfectly good original cells! I have checked on 13 batteries: only TWO had one or two bad cells, and the rest were all still perfectly usable, accepting the rated Ah of charge and discharge. I have even repurposed three of the 3600 mAh 25.2V, extricating the cell packs and throwing out the bms's! They now work on an APC 1000VA UPS.

Another 21.6V 2.6Ah unit received a different bms, and powers an 18V cordless drill.

I have only a V11 motor unit, which I have never once been able to run. None of the 13 batteries would fit ideally, so I have tried with bench power supplies, up to 30V, 25A. Apparently, pressing the trigger sends a code from the motor unit to the battery to wake it up. The battery then enables the motor if it has enough charge. Not knowing this communication protocol, one can never power the motor. This is precisely where eevblog wise ones can help!.
 
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Offline SilverSolder

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #34 on: December 15, 2021, 08:45:24 pm »

Killing the environment with disposable, self bricking products...   that's what some manufacturers make a good living from.  The authorities should really be more on the ball about this kind of thing....
 

Offline NiHaoMike

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #35 on: December 16, 2021, 01:58:58 am »
The mod I did to mine is to add more 18650s in parallel with the existing ones when the pack started getting weak. Now I have a cordless vacuum that rarely needs charging. What I would like to do next is 3D print an extension to the dust can so I don't have to empty it so often, but it looks to be quite a challenge to get it to fit right.
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Offline tinfever

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #36 on: December 18, 2021, 02:21:01 am »
I left my Dyson V7 off the charger for a few weeks until I got around to cleaning it and I'm now the proud owner of a battery pack that only blinks red 32 times if you try to use it. I thought I might chime in on the fight to get the things working again. The cells in mine are slightly out of balance but all between 3.4-4.1V.

After much digging (literally, through the potting compound), it appears that my 6-cell battery pack is run by what is probably a PIC16LF1847-I/MV microcontroller with a Renesas/Infineon ISL94208 battery management IC.

Getting the whole thing desoldered was interesting and there were a few sparking incidents so now the fuse (F1) is blown. I just soldered a small piece of wire over the fuse for now. I've soldered pin headers to each of the terminals and then used a resistor divider network with 330R resistors to simulate the voltages as if the board were connected to a battery back (24V from bench PSU, 20V, 16V, 12V, 8V, 4V, GND). If I bring a magnet near the reed switch, with everything powered up, the red LED still blinks 32 times so I don't think the microcontroller knows it is a brain with no body. ;D

I doubt this is possible but it sure would be convenient if the four plated through holes to the right of the PIC (which I've populated with headers) were the debug/programmer pins for the PIC and Dyson forgot to prevent the firmware from being able to be dumped. Then, ideally, we could dump the firmware, change ENABLE_PLANNED_OBSOLENECE_TIMER from 1 to 0, and then anyone with this issue could reflash the PIC with fixed firmware by just poking through the potting compound in those header locations.

Now that I think of it, I wonder how blatant the firmware is written as far as this planned obsolescence goes...
 

Offline tinfever

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #37 on: December 19, 2021, 05:51:57 am »
I'm pretty sure I've figured out the pinout of the headers and they contain all the correct pins for programming the PIC microcontroller. I bought a PicKit 3 to attempt to talk to it but haven't had much luck so far. I've just been trying to use the PicKit to power the device to read the memory and I'm only getting the error "Target Device ID (0x3fe0) is an Invalid Device ID. Please check your connections to the Target Device." which from reading only it sounds like that can mean almost anything. I thought I got it to work once where I saw a message like "Target PIC16LF1847 recognized" or something but haven't been able to reproduce that. It's entirely possible my connections are dodgy so I need to do some more testing. I'm seeing activity on the oscilloscope but I don't know if that's just the PicKit just sending commands or the MCU actually responding. I've confirmed the PicKit is providing 3.25V to the MCU which should power it. (For the record, I'm totally out of my depth on anything software related so I certainly wouldn't turn down some help.)

I also think the 3.3V power for the MCU is coming from an internal regulator function on the ISL BMS IC which can apparently control a transistor to generate a regulated 3.3V output.

I've attached the best board photos (bottom side is mirrored) I could take with an overlay of the small portion of the circuitry I've figured out, also including pinouts of the two ICs in question.
« Last Edit: December 19, 2021, 05:59:59 am by tinfever »
 
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Offline tinfever

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #38 on: December 19, 2021, 11:02:43 pm »
I think I'm able to more reliably connect to the PIC MCU, although I'm not sure what's different now. I think the next step would be to figure out if the copy protection bits are set and try to read the memory. I'm able to click the "Read" button on MPLAB IPE and then it looks like it works, but any output I get seems pretty much empty. What's weird is that sometimes I get different results depending on exactly how I connect to the PIC. Sometimes I'll read the memory and look at the configuration bits window to see the copy protection bits are set to OFF, then I'll do something and read again and it's say they are set to on. Sometimes it also includes a message about the debug bit being set or something like that. I'm not really sure what's going on.

I've attached some screenshots and the dumps I've gotten so far. I'm pretty sure the dumps are empty or worthless though.
 

Offline SilverSolder

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #39 on: December 20, 2021, 11:01:04 pm »

Is it not possible to simply replace the battery management chip with a more generic version?  Or does the battery communicate with the "mother ship"?  (Be glad that we're not yet at the stage where the battery needs Internet access to work,  you can be sure our children or grandchildren will be dealing with that...)

 

Offline tinfever

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #40 on: December 21, 2021, 12:48:12 am »
I already ordered a replacement BMS board from Aliexpress. At least on my V7 vacuum, the "communication" with the battery is very simple. When you pull the trigger on the vacuum, it moves a lever that actually physically pushes a button built in to the battery pack. When the button is pushed, if the reed switch is closed (indicating the battery is inside the vacuum), if the MCU is happy it presumably send a "go" command over I2C to the BMS IC and the BMS IC will then charge the gate of the discharge MOSFET to electrically connect the battery cells to the vacuum. I believe as long as the vacuum gets power, it doesn't care where it comes from, which is why there are people making/selling adapters for you to use Makita tool batteries on them.

If I had more time, and if I'm unable to dump the existing firmware, it sounds like a fun project to make new firmware for the PIC to replace Dyson's. It probably only sounds fun and easy because I haven't done it before though...

Edit: I've started a new thread in the Microcontroller category regarding dumping the firmware or at least confirming the read protection bits are definitely set: https://www.eevblog.com/forum/microcontrollers/pic-attempting-to-dump-firmware-on-pic16lf1847-from-dyson-battery/
« Last Edit: December 21, 2021, 01:24:11 am by tinfever »
 
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Offline dvd4me

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #41 on: December 22, 2021, 01:52:59 am »
Hello,
Is the ISL94208 battery manager used in other power hand tools? It must be using similar PIC control since the ISL94208 communication is via I2C.
Maybe some I2C commands can be sent to ISL94208 to unlock the charge/discharge and detach the I2C bus from the PIC control.
Maybe the pack can be rendered in a more " dumb" state, but still usable, not locked. Any thoughts?
 

Offline dvd4me

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #42 on: December 23, 2021, 02:26:15 am »
I already ordered a replacement BMS board from Aliexpress. At least on my V7 vacuum, the "communication" with the battery is very simple. When you pull the trigger on the vacuum, it moves a lever that actually physically pushes a button built in to the battery pack. When the button is pushed, if the reed switch is closed (indicating the battery is inside the vacuum), if the MCU is happy it presumably send a "go" command over I2C to the BMS IC and the BMS IC will then charge the gate of the discharge MOSFET to electrically connect the battery cells to the vacuum. I believe as long as the vacuum gets power, it doesn't care where it comes from, which is why there are people making/selling adapters for you to use Makita tool batteries on them.

If I had more time, and if I'm unable to dump the existing firmware, it sounds like a fun project to make new firmware for the PIC to replace Dyson's. It probably only sounds fun and easy because I haven't done it before though...

Edit: I've started a new thread in the Microcontroller category regarding dumping the firmware or at least confirming the read protection bits are definitely set: https://www.eevblog.com/forum/microcontrollers/pic-attempting-to-dump-firmware-on-pic16lf1847-from-dyson-battery/
Hello again, I replied also in the microcontroller thread, this guy Robin actually used the ISL94208 battery manager to build his own 6 cell pack ( sic) and used an atmega microcotroller for it. I just send him an email, maybe he want to help and contribute to this battery salvage project, since I see no chance you can actually read the original Dyson locked PIC to get the code and modify the lock flag.
Imagine saving hundreds if not thousands of these batteries from being discarded. That would be great!
 
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Offline SilverSolder

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #43 on: December 27, 2021, 03:10:26 pm »

It would be awesome if a replacement board of some kind could be conjured up!

Obviously it is a problem if the cells really are toast, though....   Are there good ways to test the cells to make sure there is enough life left in them to make it worth the bother to repurpose them like this?
 

Offline Craftsman

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #44 on: December 30, 2021, 11:08:13 pm »
There are 'replacement' boards available on Aliexpress like this one - https://www.aliexpress.com/item/1005003640893416.html.  You can even get the whole works except the batteries for a few bucks more - https://www.aliexpress.com/item/1005003742394449.html.

 
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Offline Craftsman

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #45 on: December 30, 2021, 11:20:18 pm »
Interesting thread. Thanks to everyone for their contributions.

One thing I haven't seen mentioned which may be worth investigating is can we prevent a pack failure from happening in the first place so that we don't have to try to resurrect a 'dead' pack?  From what I can see, all failed packs seem to have one thing in common - the individual cells fall out of balance.  I don't know how in balanced they were when the pack was new but I would assume that they were a heck of a lot closer than what people have posted.  A few have put forward theories on how the BMS reacts to cause a pack death - the voltage of the pack drops below X brings the pack closer to death.  With the cells being drastically out of balance, it's possible that as the cells become more unbalanced, more low voltage situations happens until at some point a threshold is reached and the BMS decides that life is not worth living anymore.

How about we intervene before the pack hits that point by regularly balancing out the charge on the individual cells manually BEFORE the pack is declared dead by the BMS?  For example, we could balance a pack's cells annually, then in theory, the pack's counter may never advance.  This is assuming, of course, that the pack's cells steady become more out of balance with each charge/discharge and on a pack that is still good (let's say a 1 year old pack) if we put the cells back into balance, we would be extending the life of the pack.

I may be wrong, but prevention may be the only route here.
 
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Offline dvd4me

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #46 on: January 03, 2022, 05:44:40 am »
Interesting thread. Thanks to everyone for their contributions.

How about we intervene before the pack hits that point by regularly balancing out the charge on the individual cells manually BEFORE the pack is declared dead by the BMS?
I may be wrong, but prevention may be the only route here.
Hello Craftsman,

I have locked the original V6 BMS by mistake, while trying to measure capacity directly on cells. I was running a couple of charge discharge cycles directly on the cells. Big mistake, charge/discharge must run thru the BMS. Edit: if the BMS is awake and not in deep sleep mode.

I was lucky to find at Home Depot in the recycling box another V6 battery, just last Friday. I open-it and the first thing I checked, it was already charged, at around 4.0V each cell . Checked all the cells, a bit unbalanced. Run a discharge cycle until the BMS cuts the power off. The lowest battery was at 3.3V. ( EDIT: it stops at 3.1V and in my case it slowly recovers to 3.3V)  I connected a cell balancing device, used for LI-PO's, and discharged all cells to the same 3.3v.
Then charge with the charger and run a measured discharge cycle (in the picture it shows a V7 battery while testing the capacity, this V7 battery I found-it some time ago. I used-it to experiment how to re-balance and measure capacity after I locked the V6 BMS).
The V6 battery I found last week now shows a decent 1650mAh, after balancing.
I understood that the battery managing chip should be able to do balancing, maybe Dyson did not implemented the algorithm in the PIC that controls it...
So as a prevention, I believe a 6S balancing header ( i only had a 3S header to solder on the cells) that can be pulled out of the case and connect every now and then to a balancing device.
Also never try to balance by charging the weak cells, that's what kills the BMS, detecting battery voltage increase without charging. ( EDIT: I assume if the BMS is in deep sleep mode, it can be charged/balanced )

I believe it's safe to discharge to 3.4V (EDIT: 3.2V or higher.)
Never discharge lower than EDIT: 3.1V, I believe that is the threshold BMS stops the discharge by itself. Lower than that may trigger the BMS to lock.
Now that I have ordered a 6S balance header I will find a way to pass the wires safely thru a hole in the battery case.
I now have the locked BMS from the original battery to experiment on it. I also ordered the Ali BMS but I would prefer to re-program the PIC if possible to revive-it, similar with user tinfever was trying to do.

Best,
« Last Edit: January 13, 2022, 04:25:06 am by dvd4me »
 
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Offline Craftsman

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #47 on: January 03, 2022, 11:49:36 pm »
Thanks for the clarification about the BMS and charging. 

One thing of concern about discharging individual cells down to 3.4V might be that during the discharge, we might trip a trigger point of 3.3V on the BMS accidentally.  A better alternative may be:

1. charge the pack through the BMS until full;
2. measure the voltage of each cell;
3. discharge the cells down to the lowest cell provided that the lowest cell is not below 3.5V (just a bit of safety just in case).  If it is below 3.5V, then discharge down to 3.5V;
4. Start back at 1 until the pack is somewhat balanced.

I realize that going down to 3.5V might take an extra cycle or two to get a balanced set of cells but we just don't what the PIC's criteria is for locking up so it's better safe than sorry.
 

Offline najrao

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #48 on: January 04, 2022, 09:52:43 am »
I already ordered a replacement BMS board from Aliexpress. At least on my V7 vacuum, the "communication" with the battery is very simple.  the gate of the discharge MOSFET to electrically connect the battery cells to the vacuWhen you pull the trigger on the vacuum, it moves a lever that actually physically pushes a button built in to the battery pack. When the button is pushed, if the reed switch is closed (indicating the battery is inside the vacuum), if the MCU is happy it presumably send a "go" command over I2C to the BMS IC and the BMS IC will then chargeum. I believe as long as the vacuum gets power, it doesn't care where it comes from, which is why there are people making/selling adapters for you to use Makita tool batteries on them.

If I had more time, and if I'm unable to dump the existing firmware, it sounds like a fun project to make new firmware for the PIC to replace Dyson's. It probably only sounds fun and easy because I haven't done it before though...

Edit: I've started a new thread in the Microcontroller category regarding dumping the firmware or at least confirming the read protection bits are definitely set: https://www.eevblog.com/forum/microcontrollers/pic-attempting-to-dump-firmware-on-pic16lf1847-from-dyson-battery/
I have what I believe is a V11 "absolute" motor and cyclone unit (no model no. on item, but compared pictures). None of the umpteen discarded batteries with me seem to fit exactly on this. Given the source, I do not know for sure that my motor unit is free of defect, but it was all very clean inside.
Connecting a (high enough current) dc supply to the power in terminals does not even turn on the display, but there is a current draw of some 30mA. The motor-to-battery communication port does put out an undecipherable sequence of signals, sighted on oscilloscope. Note also that the feed for the brush motor was open.
I tried to trick it to wake up by feeding the motor's signal to another Dyson 25.2V battery, while still fed by other PSU. No prize offered for guessing: nothing happened. (This is perhaps a V10 battery, and has very good cells but its bms has the orange blink scourge).
I might have shown that there is more to it than just the nefarious battery BMS. No conclusion just yet.
« Last Edit: January 07, 2022, 04:44:48 am by najrao »
 

Offline najrao

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Re: Dyson v7 Trigger cordless vacuum - TEARDOWN of battery pack
« Reply #49 on: January 04, 2022, 11:41:57 am »
As a side question, may I ask:
Also have just the motor, of a V7? (may be V6), pictured. What connects to J5? It has 10 points to connect. Suspect it leads to a two-position switch on the top of the assembly, for selecting normal or boost, but I don't know such. If so, can anybody tell me the wiring of this?
This motor also talks to the battery, via J8, just two pins.
Powering up the screw terminals as is does nothing, except a small current draw.
I have detached the board to reveal the back of it. There are four mosfets in a H bridge, and three 270uF bus caps; all test good in circuit. The shaft can be rotated against 'detents'. But I cannot run it at all.
Nothing hangs on this, I am just very interested in seeing it in operation.
« Last Edit: January 13, 2022, 04:45:16 am by najrao »
 


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