Spoiler Saver Please remember that this is just for entertainment, what you will see in this video IS DANGEROUS!!!! Please do not copy anything that you see! I hope you enjoy it.
Already salvaged a few 18650 from a power tool battery, just one out of 10 was bad, useful cells to have hanging around I am powering my bike lights off them :), also I agree if you don't know what you are doing don't play with them, and definitely don't solder them.
Pro tip: take off your wedding ring when working on energized circuitry - or get a silicone ring. You could easily lose that finger if the battery welded itself to the ring. I still have a large scar from a metal watch-band that exploded when working on a car near the starter (the battery lead is always hot). I cringed every time you touched the sides of the battery with your ring on. Stay safe, I love the content, cheers!
Nearly mentioned the same thing in my comment Thomas...couple of years ago I managed to short a laptop cell on my ring and suffered with severe burns for weeks - super heating to say the least!
The mosfet besides the cap is probably blown. You can replace it with a mosfet from taken a motherboard. Measure in diode mode between source and drain, you should get 0.4 to 0.7 V.
Great video! The circuit board is for balancing the cells, if you charge a few cells, the voltage will drop because it's being redistributed over all cells. Either connect the battery to a full other battery(with enough discharge) or charge each cell separate bypassing the board. Smart chargers will most likely detect the battery once it's about 15Volts
One trick to make the solder stick to the battery ends is to scratch it before soldering. So the solder has a mechanical connection with the battery. I repaired a vacuum like that and is going really strong. This will also make it easier to solder, you don't need to apply so much heat because the solder will flow to the scratches and grab into.
If cells drop below 2.7v the bms ic will destroy circuit for protection. I guess that ic is BQ and they will destroy the fuse near cells to protect them and some newer BQ types will lock themselves. In this case you can charge them from output so it’s look like that just ic is locked. You can try unlocking it by shorting data and clock to ground. If that doesn’t help, you will need to reprogram it. But, if you want to program it, be aware that in mostly cases, manufacturers protect them with the password.
Interesting. I was speculating the chip next to the replaced cap was effectively a system management controller that had gone brain dead. I assume it talks to the charger to relay system health (of the battery) and it was bad
On these batteries unless its something serious the IC bricks itself after 3 failed charge attempts. Good luck for anyone trying to hack these and unlock them. Tons of talented people have tried but Milwaukee has put lots of money into making them unfixable. However what you can do is get a new grey market board if you've charged the cells. This bricking behavior is why if it flashes red and green due to low charge it's important not to attempt again but to manually charge it back up. All of this is pretty readily available info.
I have worked with a lot of failed 18/36v batteries. I normally use a current limited supply across the whole battery set to the equivalent of 2.5v per cell and the current limit at 50ma per cell (150ma for 3 in parallel). Usually find most of the cells quickly (mins not hrs) rise to 2.5v if they haven't leaked and started rusting out. I find the bms is often the problem or is deliberately blocking re-use due to past excessive discharge. I end up discarding typically one bank per battery at most.
Unfortunately you cannot measure the resistance of a power source like a battery with your ohm meter. As it uses voltage to determine the resistance, it will read wrong if there is voltage.
The safety issue with charging cells that have gone that flat is simple. They need reforming. You can do that by charging them @50mA per cell up to a voltage of 2.6 and keep them there awhile. That should recondition the cells adequately enough. The board and it's components may be another story entirely. If it has a fault lockout like other commenters have mentioned it could be completely rooted. The real acid test for the cells is to charge them and see if they keep it without self discharge over a reasonable amount of time.
I really enjoy your warts and all videos on repair strategies. It's always entertaining. I really enjoy the dépistage and admire how you refuse to quit
Hi there my name's TheCod3r from your mate TheCod3r dcom and in this comment today is another comment telling you to keep up the great work! Looking forward to this one
Protip when using continuity in-circuit: Always check both ways. Your meter uses voltage to check for continuity. However, the circuit may have voltages across two points that will provide a false reading. I learned this fairly quickly when doing car fuses. All fuses read perfectly, including blown ones, until out of circuit.
Don't know if this has already been mentioned but Doctor Lefthandthread replaced a Milwaukee battery CB with a knock off one to revive the unit in one of his videos, so they must be available. Love the videos Vince, keep 'em coming.
Buy a cheap used 2ah battery and swap out the circuit board, or even a cheap clone battery and use that circuit board. It would certainly be interesting to see if you can get it working. Great vid, really enjoyed it.
They also use the new 21000 cells instead of the older type 18950 cells so different boards used to deal with the faster charging and 50% higher output power 🔋
I hate to chime in so late my friend, but I couldn't help notice the fuse was possibly the cause of the scorching. A damaged trace was loose and all the solder appeared to have vapourized.Thrown off by the continuity test you did as I have been many times. Funny that the fuse didn't blow from whatever the cause. Not that the resoldering of that fuse would solve the problem of course, but I bet the board would come to life for a better prognosis. These HD12 are very expensive. I have one on my bench that reads 17V all groups of 3 are in at 3.36V and yet the first LED blinks 8 times. I have not been able to find any damage to the board. Going to have a much closer look at the PCB and all. Here in Canada these cost $379 CAD
The black burnt thing you IPAed off was the bug- a worm or slug. Cant check resistance on a battery as it is a power source and will screw up the resistance measurement. The sets of parallel batteries ALTERNATE polarity - think batteries end to end like in a flashlight except in this case back and forth. Recharging fully discharged lithium cells is NOT unsafe (I've recharged HUNDREDS of fully discharged cells and lipos), the full discharge just reduces battery capacity sometimes all the way down to NO capacity.. The dangerous thing you did was to REVERSE POLARITY most of the other parallel sets. The way I rescue packs is to use a TP4056 and charge each parallel bank slowly. Your cells are probably around 4Ah and when in parallel (by threes) will be 4Ah x 3 or 12Ah and charging lithium batteries is safe at up to 1C so 12Amps per bank. Really safe at 1A of the TP4052 charger.
I took a Makita apart few yrs back . The 1st cell always goes faulty if you run right down . Then the micro chip tells it battery is no good and to stop changing. I gave up in the end and bought a new battery
As per another post, when the BMS chip sees an issue and stops the ability to charge, this is not resettable. You can swap the charge board + chip for a cheap clone, but that's about all. They build the failure mode as permanent for safety. There was nothing you could do.
Might sound silly but did you check the fuse again after you had done all the work? Maybe have another look at the board and continue to fault find. Might be more than 1 failure
Are there two boards in the battery ? has the board been put back in place the correct way ? at 28:35 the copper heat sink is below the board but later it is above the board .
I just bought myself a nice new set of Makita LXT tools (SDS, Combi Drill, Screw Gun, Angle Grinder and Circular Saw) and I was gobsmacked. £120 for a battery and charger and they don't even come with the tools. Really is unbelievable how much they can charge for a few basic 18650s
Defiantly worth getting a battery welder, even just a small portable one as they are so much easier to use with these cells. Have you thought of just getting another 3P 5S BMS to manage the charging? It wont do all the LED's but may let you charge from the Milwaulkee charger
With the Milwaukee I've heard that the rapid charger won't charge a battery if it gets too low the regular slower charger will that's why they run deals to get all the batteries sold about twice a year so they don't die on the shelves
Isn't that a knockoff? I have 4 of those 12.0 high output batteries and the side labels are very different from that one. Unless they use different stickers for what they ship to the UK?
If I was a company that doesn't want its equipment go up in flames, I'd put protection onto the controller board, that triggers when something goes wrong. You'll probably have to reset that for the charger to work again.
I know its over a year later and you may not care, but the Cap value on my board is 10uf. It is suprising that it's that large so I checked on the 12ah and double checked on the 8ah board. They are both showing 10uf. I have been working on one of these 12ah for a while now off and on. The boards on these HO packs are strange. Both the 12ah and the 8ah, once I removed the power from them to do a reset now they will not power on. Both boards did just like yours. No power. This maybe a HO pack issue? Just throwing it out there as I try to edit my video while troubleshooting mine. I hope collectively we can figure out much more about them. I do know the cells in these has issues with the 1st gen and Samsung now has the V3 of this cell out now. Take care!
I know there are Makita knock-off BMSs. Maybe there's a possibility of finding one for this, or, a generic BMS that you can hookup that will prevent over discharge and over charging. You would still have to charge it with your bench power supply, but, you would have protection for the battery pack. You could even have a battery indicator with a pushbutton to check power level.
Great video Vince =D I think you're right regards the cap being the initial fault. Cells then drained, some more than others =/ That cap size, it may be 100nF, could also be 1uF, or 10uF maybe? Likely won't make much difference I think. Either side of that area where what looked like 2 mosfets, maybe one of those had failed too? Regards desoldering batteries etc - the time they are most dangerous is when they have charge, that's where the explosive energy is, although chemical reactions can create energy too. So when dealing with a battery where its almost completely flat, there's a lot less chance of a major runaway reaction. The risk is when charging, or draining high current (or puncturing / heating a battery with charge). You might be able to get a 3rd party charge circuit for that - mod it to balance charge using a different supply maybe - but probably more hastle than its worth... I certainly wouldn't like a fault to develop in a battery like that, the fire that follows could be quite something with so many cells in such close proximity! What ever you do I wouldn't charge that unattended, although it seems like the batteries are good quality and fairly well balanced!
Thanks for the advice Chris. I'm hoping it will only need charging once a year to power that work light. If it becomes a regular thing that needs charging, then nerves will get the better of me and I will leave it be. Even when I was charging it then, I was checking for heat build up obsessively every few minutes🤣🤣 It is so complicated and I'm gutted the cap and cells didn't fix it. Thanks Gadget 👍👍👍👍👍
Looks like this pack is built similarly to a laptop battery. Those battery controller ICs will disable themselves as soon as the cell voltage (even on one single cell) goes too low. They can be reset, but it's not a trivial thing to do. Interestingly, I've encountered exactly the same situation when salvaging cells from a very old (~20 years) Dell battery. Out of 3 banks, one was OK (even had OK capacity), other two were totally shorted. Well, at least now you have some good quality Samsung cells which most likely can still be charged individually. I've charged dead (close to 0 V) cells before - those with at least some trace voltage present usually will still take a charge. I would charge them at low current and watch out for them while charging to make sure they aren't getting hot. I would also check for self-discharge some time after charging. Expect capacity to be degraded. I would not risk charging cells with totally 0V on them though as they can be (and usually are) internally shorted.
try disconnecting the end terminals from the board then add cells a bank at a time starting at the negative end. you need all the cells ready to be monitored once you connect the final positive. every time you connect the BMS in the wrong order - it sees the missing bank as a fault and shuts down again.
Milwaukee M18 boards lock out as soon as you disconnect them. Doesn't really matter what you do after it crosses that low voltage threshold...it will never work again. Maybe a certified Milwaukee repair shop will have a tool to reset them...but for a DIY person Milwaukee screws you.
There is a little tab underneath one of the (+) terminal on the cell which breaks contact (hence 0.0v). You can stick a small needle under the (+) terminal and reset that breaker. This is not recommended but it is possible for educational purposes.
Hi Vince, I'm trying to fix a playstation 4 controller with trace damage and thought to ask you what the product was that you painted onto the plastic pcb that leads to the l1 l2 buttons, and where can I buy some? Thanks for any help
I know some battary protection circuits record data on the battary and if they know the battery is dead they wont let the battery charge, had it on laptops when I try to rebuild the packs
I know makita boards lock up and you have to replace the board. Also shows how good guarantees are any trick in the book to worm out of replacing stuff
I don't know if someone has already commented on this, but you cannot test for a short on a battery with a multi meter, try it with a known good battery and you will see for your self. The above is also true for internal battery resistance.
Bug or metal shavings is my theory. A bug is possible because some bugs zap themselves over and over again and cause a huge mess burning up. This looks like bug damage based on how wide the area is and the type of damage. Metal shavings as you can imagine and guess can cause a nasty short too but usually those burn out fast and hard. Edit: noticed the thick board coating, probably not bug damage or shavings.
If the batteries are below 1v you need to take them out of the casing remove the welds. Then individually charge them at low amperage. Start with 100mil amp. until they get to 2.25v. then they will charge normally. I then wait a week after fully charged to see if the lose voltage. Any that drop below 4v after a week i get rid of and replace. Batteries that are deep drained can be renewed. Using you bench power supply. Once the get passed 2.25v you can up the amperage to .5amps. I have never had issues with Lithium cells. Its just a case of making sure the cells when in series and parallel are balanced. When you put them back in the pack they will self balance when in situ but most pack have a balancing control unit on the battery back. Just need to find a similar capacity and test the drain time.
Alot of milwaukee tools have a Battery Gauge built into the tool itself. So you could still monitor the battery if you have a tool with gauge built in.
You are priceless! You need to start a don’t try this at home channel ! Starts with : Not sure if this is going to work??? Buys the 12 amp hr battery! Buys the cheapest Milwaukee light ! Doesn’t own any other Milwaukee tools ! Complains how expensive they are ! Has his wedding ring on oblivious to the fact he could accidentally weld his finger to battery ! You remind me of my old School teacher ! Mr. Arnold ! Of course Students remember him as just Arnie !
My father has dozens and dozens of Milwaykee powertools, never used better tools! He even have about 6 Milwaykee radios/loud speakers (which uses these same batteries) and a Milwaykee pool table which he won from some draw :D
The board/bms may be damaged after the capacitor issue but the bms may have turned off because of the zero battery voltage. You could try to reactivate the bms. You could try taking a jumper wire and touch it against the positive end of the battery pack before it connects to the board/bms. While holding it in place touch the other end of the jumper wire to the positive output of the board, the positive pin that connects to the charger. Hold it for a second then press the button to see if the bms has woken up. It works with laptop 18650 packs and their bms. If not your probably stuck, 10 out of 10 for effort though. Also if the bms isn't working your light will probably deplete the batteries below their safe 2.5v if you don't keep checking. I won't lie, I was waiting for a bang 😅
From my previous play with 18650 cells I can say even though it’s not safe I have slow charged single cells at a time on a very slow rate NMHB of .2amps and got cells to come back to life. Your safety aside it did bring the cells back and lasted about 3 years till they finally did not want to hold a charge anymore.
Battery test lights works independently so you can check state of charge before fitting My batteries get hot when charging but never thought it was dangerous Even bought Chinese copies and seem to work well So expensive torch next revisit you will have reworked a charge jack plug within ? saves you stripping it down again to charge .. even a fly lead ?
48:50 I was waiting when the ring makes contact with the batteries and start glowing red hot and leave 'nice' imprint in finger. I must say this guy is much braver than I. I would have taken ring off 'just in case'.
Great attempt, but from the getgo I was worried the selfdestructing electronics in these batteries would sabotage your attempt … Do you have any knowledge on the charging protocol/pinout of Milwaukee batteries ? Pins 1 and 5 are for discharging, but I’d love to balance charge my batteries with a CC/CV lab power supply. I think pin 3 is involved, but I wonder if anyone knows for sure … Since yours was defective, pin 3 may have been disabled.
hi i have 2 m28 milwaukee batteries that show 27 volts on the inner negative and the single positive but shows zero on the outer negative. and it shows flashing red green on charger and only one display light on .could i bridge the inner negative to the outer ?
I don't think this has been mentioned but have you tried to reset those 'dead' cells? A little known fact is that good quality 'branded' cells (like these 21700's) have a safety cut-off button under the positive end of the cell. It pops up when over-discharged and physically disconnects the positive end of the cell. As only some of those 15 cells appear 'dead' this may be the reason...so...IF and only IF a cell reads 0 (zero) volts then try to reset the cell.....here's how: (there are videos online of this if my explanation is rubbish) A small jewellers screwdriver, although a plastic alternative would be much safer, can be used to 'push' the button back down toward the cell. Access is gained through those slits around the positive end. Insert the prying device of choice into one of those slits and gently push downward.....remembering that IF this does reset the cell it will instantly become 'live' again. Best practice is to do this very gently in stages....measure the voltage after each atempt. It does not take much to reset. The button is very much like the metal contact under a push button switch....I know you know of these...I've seen you mend them, so you know how little force is required to move them. You probably won't actually feel anything move or click or even make a sound but go slowly and test after each try....if you get any voltage at all then at least the cell will be 'active' again. No guarantee this is the problem but I've had laptop cells do this on a regular basis, some shut down others don't, just as you have here. I hope you at least give it a go, what have you to lose? You may get a few cells back....just be carefull, common sense, oh and remove your wedding ring if you're going to pat the top of a live circuit board. Stay safe.
Hi watch all your videos with great interest just to help you out a you tuber called Andy mechanic has previously done some videos on repairing milwaukee batteries and he had to replace the circuit board after he replaced the damaged cells in the battery. Keep up the fantastic educational videos.
What a great video, I know its just for entertainment but how interesting. My guess is that it has a bug in it but it wasn't the cause of the fault. To avoid infestation of service facilities its not unusual for companies to just refuse to repair anything with an insect in it. Just a thought. Anyways solid entertainment! Cheers!
Those 18650 cells does have an internal fuse against overcharge, the temperature raises too much It cuts off. You'll ser they have 0 volts. You can get around that putting It on a vice and pressing the plus nipple a little bit so it closes the circuit again. It's dangerous though, it's safer and not expensive replacing those cells. You can be sure something went south with that BMS as It demanded so much current from one or more cell that it fried.
first of all those are 21700 batteries, and second no they dont ave any internal protections on them hence the reason they are prone to bursting into flames when they fail. he even pulls the spec sheet up on them in the video and you can clearly see where it says that there is NO protection on these cells
Would be interesting if you bought one of the replacement charging PCBs from eBay and see if you could make it work with that. I sadly cant find the 12ah version but maybe take some cells out and make it a 9ah version because those PCBs are easy to find
The burn looked like it went from the contact the the closest IC contact... I wonder if that is a power or ground there! Maybe see about recovering a replacement board from another dead battery or online a replacement board?
18650 batteries have built in safety in case of overcharging/short circuit where a thin disc on the positive terminal ‘pops’ up and renders the battery useless. These can be reset Vince. Look into it and you’ll be surprised what u find 😉
Have you traded on the Milwaukee charger again yet because since you got the voltage that it needs back into the battery the charger is looking for above 16 V to charge the battery the Milwaukee charger might work now
You may call me crazy, but there was a hack to revive Ryobi LiIon battery, once it dropped below the threshold where the charger would think it was broken. Basically, you'd take a 12v battery charger, set to the 2ah setting and for just a second, tap the positive and negative. It would temp charge the cells to a high enough voltage to go above the threshold and allow to charge normally. Just editing to clarify, you'd tap the charger leads to the battery pack buss positive and negative, not individual cells.
You can bump charge them to initiate the ability for a charger to commence a charge cycle . I use a Rc charger for this . Make sure that you keep an eye for heaters ( any heaters remove and discharge / recycle ) But you will be surprised how many cells will work and be close to there full capacity and reusable - allows to sit for 4 weeks to see it they have internal shorts and use common sense !!! Ie do all this outside in a shed @ you own risk
Spoiler Saver
Please remember that this is just for entertainment, what you will see in this video IS DANGEROUS!!!! Please do not copy anything that you see!
I hope you enjoy it.
.
It won’t let me add the link on here but it seems there are sellers on eBay with replacement BMU circuit boards for that battery
Already salvaged a few 18650 from a power tool battery, just one out of 10 was bad, useful cells to have hanging around I am powering my bike lights off them :), also I agree if you don't know what you are doing don't play with them, and definitely don't solder them.
You can get the nickel strip and mini spot welder to rebuild the pack... the batteries i`d use laptop cells for it... :)
I love listening to British people talk!
Pro tip: take off your wedding ring when working on energized circuitry - or get a silicone ring. You could easily lose that finger if the battery welded itself to the ring. I still have a large scar from a metal watch-band that exploded when working on a car near the starter (the battery lead is always hot). I cringed every time you touched the sides of the battery with your ring on. Stay safe, I love the content, cheers!
More people to like this so he sees it
Nearly mentioned the same thing in my comment Thomas...couple of years ago I managed to short a laptop cell on my ring and suffered with severe burns for weeks - super heating to say the least!
Aka: Don't get married if you wanna live. 😂😂😂
Very good comment. However funny it would be to say "I'm watching 9finger Vince" I would rather Vince keeps all his fingers 😁
Nothing like a battery burn to wake you up! I worked on cell packs for years as you say first rule take your watch and ring off!!
Vince when you're using low melt solder be sure to add flux to help it flow and mix in with the regular solder. It makes a huge difference! :)
The mosfet besides the cap is probably blown. You can replace it with a mosfet from taken a motherboard. Measure in diode mode between source and drain, you should get 0.4 to 0.7 V.
I have zero reason to watch this
I just watched the whole thing for some reason and found it very interesting! Thanks
these videos are so satisfying and they help me settle down to sleep
Great video!
The circuit board is for balancing the cells, if you charge a few cells, the voltage will drop because it's being redistributed over all cells. Either connect the battery to a full other battery(with enough discharge) or charge each cell separate bypassing the board. Smart chargers will most likely detect the battery once it's about 15Volts
One trick to make the solder stick to the battery ends is to scratch it before soldering. So the solder has a mechanical connection with the battery. I repaired a vacuum like that and is going really strong. This will also make it easier to solder, you don't need to apply so much heat because the solder will flow to the scratches and grab into.
Solder simply needs clean, bare metal and the correct flux. Solder uses a molecular level connection. No need to rough up the surface.
If cells drop below 2.7v the bms ic will destroy circuit for protection. I guess that ic is BQ and they will destroy the fuse near cells to protect them and some newer BQ types will lock themselves. In this case you can charge them from output so it’s look like that just ic is locked. You can try unlocking it by shorting data and clock to ground. If that doesn’t help, you will need to reprogram it. But, if you want to program it, be aware that in mostly cases, manufacturers protect them with the password.
So, in fact they are self destructing when they think something serious is wrong …
Interesting. I was speculating the chip next to the replaced cap was effectively a system management controller that had gone brain dead. I assume it talks to the charger to relay system health (of the battery) and it was bad
It does not "destroy" the circuit, it just shuts off the mosfets so no additional power can be drained by the tool.
On these batteries unless its something serious the IC bricks itself after 3 failed charge attempts.
Good luck for anyone trying to hack these and unlock them. Tons of talented people have tried but Milwaukee has put lots of money into making them unfixable.
However what you can do is get a new grey market board if you've charged the cells.
This bricking behavior is why if it flashes red and green due to low charge it's important not to attempt again but to manually charge it back up.
All of this is pretty readily available info.
I have worked with a lot of failed 18/36v batteries. I normally use a current limited supply across the whole battery set to the equivalent of 2.5v per cell and the current limit at 50ma per cell (150ma for 3 in parallel). Usually find most of the cells quickly (mins not hrs) rise to 2.5v if they haven't leaked and started rusting out. I find the bms is often the problem or is deliberately blocking re-use due to past excessive discharge. I end up discarding typically one bank per battery at most.
Time to buy a Mini battery spot welder. A lot less chance of heat damage to batteries. Thanks for the Vids Cuzz. Rockford,IL USA
Unfortunately you cannot measure the resistance of a power source like a battery with your ohm meter. As it uses voltage to determine the resistance, it will read wrong if there is voltage.
Always happy to make some time to relax and watch Vince play with dangerous things!
The safety issue with charging cells that have gone that flat is simple. They need reforming. You can do that by charging them @50mA per cell up to a voltage of 2.6 and keep them there awhile. That should recondition the cells adequately enough. The board and it's components may be another story entirely. If it has a fault lockout like other commenters have mentioned it could be completely rooted. The real acid test for the cells is to charge them and see if they keep it without self discharge over a reasonable amount of time.
I really enjoy your warts and all videos on repair strategies. It's always entertaining. I really enjoy the dépistage and admire how you refuse to quit
Hi there my name's TheCod3r from your mate TheCod3r dcom and in this comment today is another comment telling you to keep up the great work! Looking forward to this one
Protip when using continuity in-circuit: Always check both ways. Your meter uses voltage to check for continuity. However, the circuit may have voltages across two points that will provide a false reading. I learned this fairly quickly when doing car fuses. All fuses read perfectly, including blown ones, until out of circuit.
33:15 never thought about that, only 3 out of all of those batteries, kinda thought all went bad at same time. 👍 Good info
Very strange how 3 survived. Cheers Paul 👍
40:23 Battery spot welder is dirt cheap
Don't know if this has already been mentioned but Doctor Lefthandthread replaced a Milwaukee battery CB with a knock off one to revive the unit in one of his videos, so they must be available. Love the videos Vince, keep 'em coming.
Buy a cheap used 2ah battery and swap out the circuit board, or even a cheap clone battery and use that circuit board. It would certainly be interesting to see if you can get it working. Great vid, really enjoyed it.
You can’t swap a 2ah, they use different bms
only the high output 6 and 8ah use the same bms
2ah and 5ah have different bms
They also use the new 21000 cells instead of the older type 18950 cells so different boards used to deal with the faster charging and 50% higher output power 🔋
Usually in this case, when you don't know the capacitor value, I would look up a nearest ic's datasheet.
I hate to chime in so late my friend, but I couldn't help notice the fuse was possibly the cause of the scorching. A damaged trace was loose and all the solder appeared to have vapourized.Thrown off by the continuity test you did as I have been many times. Funny that the fuse didn't blow from whatever the cause. Not that the resoldering of that fuse would solve the problem of course, but I bet the board would come to life for a better prognosis. These HD12 are very expensive. I have one on my bench that reads 17V all groups of 3 are in at 3.36V and yet the first LED blinks 8 times. I have not been able to find any damage to the board. Going to have a much closer look at the PCB and all. Here in Canada these cost $379 CAD
Well this way by far one of your most risky and dangerous trying to fix videos
hi mate were did you get the ruler that was in the video
The black burnt thing you IPAed off was the bug- a worm or slug. Cant check resistance on a battery as it is a power source and will screw up the resistance measurement. The sets of parallel batteries ALTERNATE polarity - think batteries end to end like in a flashlight except in this case back and forth. Recharging fully discharged lithium cells is NOT unsafe (I've recharged HUNDREDS of fully discharged cells and lipos), the full discharge just reduces battery capacity sometimes all the way down to NO capacity.. The dangerous thing you did was to REVERSE POLARITY most of the other parallel sets. The way I rescue packs is to use a TP4056 and charge each parallel bank slowly. Your cells are probably around 4Ah and when in parallel (by threes) will be 4Ah x 3 or 12Ah and charging lithium batteries is safe at up to 1C so 12Amps per bank. Really safe at 1A of the TP4052 charger.
I took a Makita apart few yrs back .
The 1st cell always goes faulty if you run right down .
Then the micro chip tells it battery is no good and to stop changing.
I gave up in the end and bought a new battery
As per another post, when the BMS chip sees an issue and stops the ability to charge, this is not resettable. You can swap the charge board + chip for a cheap clone, but that's about all. They build the failure mode as permanent for safety. There was nothing you could do.
Great video! Where can that ruler be purchased from? Thanks 👍🏻
Might sound silly but did you check the fuse again after you had done all the work? Maybe have another look at the board and continue to fault find. Might be more than 1 failure
Yeah I think he should check the board in more detail. He could get it fixed.
Are there two boards in the battery ? has the board been put back in place the correct way ? at 28:35 the copper heat sink is below the board but later it is above the board .
I just bought myself a nice new set of Makita LXT tools (SDS, Combi Drill, Screw Gun, Angle Grinder and Circular Saw) and I was gobsmacked. £120 for a battery and charger and they don't even come with the tools. Really is unbelievable how much they can charge for a few basic 18650s
Defiantly worth getting a battery welder, even just a small portable one as they are so much easier to use with these cells. Have you thought of just getting another 3P 5S BMS to manage the charging? It wont do all the LED's but may let you charge from the Milwaulkee charger
You would need a k welder with supercaps or else you can’t weld 0.3mm factory nickel strip
With the Milwaukee I've heard that the rapid charger won't charge a battery if it gets too low the regular slower charger will that's why they run deals to get all the batteries sold about twice a year so they don't die on the shelves
Isn't that a knockoff? I have 4 of those 12.0 high output batteries and the side labels are very different from that one. Unless they use different stickers for what they ship to the UK?
If I was a company that doesn't want its equipment go up in flames, I'd put protection onto the controller board, that triggers when something goes wrong. You'll probably have to reset that for the charger to work again.
I always get enjoyment from your videos, thanks again, Dave
Being not an expert in this field of electronics, but have to admire the perseverance. Sorry it didn't work out after all those expenses.
Hey Vince, great video as always. I wanted to ask, what it the blue mat you work on called?
I know its over a year later and you may not care, but the Cap value on my board is 10uf. It is suprising that it's that large so I checked on the 12ah and double checked on the 8ah board. They are both showing 10uf. I have been working on one of these 12ah for a while now off and on. The boards on these HO packs are strange. Both the 12ah and the 8ah, once I removed the power from them to do a reset now they will not power on. Both boards did just like yours. No power. This maybe a HO pack issue?
Just throwing it out there as I try to edit my video while troubleshooting mine. I hope collectively we can figure out much more about them. I do know the cells in these has issues with the 1st gen and Samsung now has the V3 of this cell out now. Take care!
I know there are Makita knock-off BMSs. Maybe there's a possibility of finding one for this, or, a generic BMS that you can hookup that will prevent over discharge and over charging. You would still have to charge it with your bench power supply, but, you would have protection for the battery pack. You could even have a battery indicator with a pushbutton to check power level.
I will check on my 18v alot smaller battery tomorrow morning, how many cells should do no difference would it?
Great video Vince =D I think you're right regards the cap being the initial fault. Cells then drained, some more than others =/ That cap size, it may be 100nF, could also be 1uF, or 10uF maybe? Likely won't make much difference I think. Either side of that area where what looked like 2 mosfets, maybe one of those had failed too? Regards desoldering batteries etc - the time they are most dangerous is when they have charge, that's where the explosive energy is, although chemical reactions can create energy too. So when dealing with a battery where its almost completely flat, there's a lot less chance of a major runaway reaction. The risk is when charging, or draining high current (or puncturing / heating a battery with charge). You might be able to get a 3rd party charge circuit for that - mod it to balance charge using a different supply maybe - but probably more hastle than its worth... I certainly wouldn't like a fault to develop in a battery like that, the fire that follows could be quite something with so many cells in such close proximity! What ever you do I wouldn't charge that unattended, although it seems like the batteries are good quality and fairly well balanced!
Thanks for the advice Chris. I'm hoping it will only need charging once a year to power that work light. If it becomes a regular thing that needs charging, then nerves will get the better of me and I will leave it be. Even when I was charging it then, I was checking for heat build up obsessively every few minutes🤣🤣 It is so complicated and I'm gutted the cap and cells didn't fix it. Thanks Gadget 👍👍👍👍👍
@@Mymatevince No worries! Did you see comments below from a few people regards a replacement charge board =O
I did Chris, they are on there way from China 👍👍
Looks like this pack is built similarly to a laptop battery. Those battery controller ICs will disable themselves as soon as the cell voltage (even on one single cell) goes too low. They can be reset, but it's not a trivial thing to do.
Interestingly, I've encountered exactly the same situation when salvaging cells from a very old (~20 years) Dell battery. Out of 3 banks, one was OK (even had OK capacity), other two were totally shorted.
Well, at least now you have some good quality Samsung cells which most likely can still be charged individually.
I've charged dead (close to 0 V) cells before - those with at least some trace voltage present usually will still take a charge. I would charge them at low current and watch out for them while charging to make sure they aren't getting hot. I would also check for self-discharge some time after charging. Expect capacity to be degraded.
I would not risk charging cells with totally 0V on them though as they can be (and usually are) internally shorted.
try disconnecting the end terminals from the board then add cells a bank at a time starting at the negative end. you need all the cells ready to be monitored once you connect the final positive. every time you connect the BMS in the wrong order - it sees the missing bank as a fault and shuts down again.
Milwaukee M18 boards lock out as soon as you disconnect them. Doesn't really matter what you do after it crosses that low voltage threshold...it will never work again.
Maybe a certified Milwaukee repair shop will have a tool to reset them...but for a DIY person Milwaukee screws you.
Been waiting for some new Vince to watch whilst I'm stuck on isolation!!
There is a little tab underneath one of the (+) terminal on the cell which breaks contact (hence 0.0v). You can stick a small needle under the (+) terminal and reset that breaker. This is not recommended but it is possible for educational purposes.
Hi sir when you say bug damage do you mean insect or beatle damage shorting the board ?
Hi Vince,
I'm trying to fix a playstation 4 controller with trace damage and thought
to ask you what the product was that you painted onto the plastic pcb
that leads to the l1 l2 buttons, and where can I buy some?
Thanks for any help
Did you remember to to check that white e fuse again as it showed that showed it wasn't open due to a shorted capacitor right next to it.
Use the Jessa Jones cap delete tool an exacto knife!
I know some battary protection circuits record data on the battary and if they know the battery is dead they wont let the battery charge, had it on laptops when I try to rebuild the packs
I know makita boards lock up and you have to replace the board. Also shows how good guarantees are any trick in the book to worm out of replacing stuff
I don't know if someone has already commented on this, but you cannot test for a short on a battery with a multi meter, try it with a known good battery and you will see for your self.
The above is also true for internal battery resistance.
Ayr is also a seaside town on the west coast of Scotland.
Indeed it was probably Scots who named it in Aus, just like Perth etc.
Bug or metal shavings is my theory.
A bug is possible because some bugs zap themselves over and over again and cause a huge mess burning up. This looks like bug damage based on how wide the area is and the type of damage.
Metal shavings as you can imagine and guess can cause a nasty short too but usually those burn out fast and hard.
Edit: noticed the thick board coating, probably not bug damage or shavings.
Could something has bugs could it be described as buggered?
where did you get the smd ruler?
Hi Vince, I learned a lot from this. Thanks for doing the video.
Great video buddy, was hooked watching this, well waiting for the “BANG” haha, unlucky though, was a great effort
I would like to see you fix the board on that battery just because I know you can I enjoy your videos Vince thank you very much
great job ! lots of patience vince .....
Around the capacitor it looks like a few MOSFET's en they may be worth checking. They are the ones switching the power.
A bug hummm as in insect? Dewalt give me the same sort of bs apparently I pulled the trigger to many times and I never received the tool back.
If the batteries are below 1v you need to take them out of the casing remove the welds. Then individually charge them at low amperage. Start with 100mil amp. until they get to 2.25v. then they will charge normally. I then wait a week after fully charged to see if the lose voltage. Any that drop below 4v after a week i get rid of and replace. Batteries that are deep drained can be renewed.
Using you bench power supply. Once the get passed 2.25v you can up the amperage to .5amps.
I have never had issues with Lithium cells. Its just a case of making sure the cells when in series and parallel are balanced. When you put them back in the pack they will self balance when in situ but most pack have a balancing control unit on the battery back.
Just need to find a similar capacity and test the drain time.
Alot of milwaukee tools have a Battery Gauge built into the tool itself. So you could still monitor the battery if you have a tool with gauge built in.
You are priceless! You need to start a don’t try this at home channel ! Starts with :
Not sure if this is going to work??? Buys the 12 amp hr battery! Buys the cheapest Milwaukee light ! Doesn’t own any other Milwaukee tools ! Complains how expensive they are ! Has his wedding ring on oblivious to the fact he could accidentally weld his finger to battery !
You remind me of my old School teacher ! Mr. Arnold ! Of course
Students remember him as just Arnie !
My father has dozens and dozens of Milwaykee powertools, never used better tools! He even have about 6 Milwaykee radios/loud speakers (which uses these same batteries) and a Milwaykee pool table which he won from some draw :D
Nobody ask you
The board/bms may be damaged after the capacitor issue but the bms may have turned off because of the zero battery voltage.
You could try to reactivate the bms.
You could try taking a jumper wire and touch it against the positive end of the battery pack before it connects to the board/bms.
While holding it in place touch the other end of the jumper wire to the positive output of the board, the positive pin that connects to the charger.
Hold it for a second then press the button to see if the bms has woken up.
It works with laptop 18650 packs and their bms.
If not your probably stuck, 10 out of 10 for effort though.
Also if the bms isn't working your light will probably deplete the batteries below their safe 2.5v if you don't keep checking.
I won't lie, I was waiting for a bang 😅
From my previous play with 18650 cells I can say even though it’s not safe I have slow charged single cells at a time on a very slow rate NMHB of .2amps and got cells to come back to life. Your safety aside it did bring the cells back and lasted about 3 years till they finally did not want to hold a charge anymore.
Battery test lights works independently so you can check state of charge before fitting
My batteries get hot when charging but never thought it was dangerous
Even bought Chinese copies and seem to work well
So expensive torch next revisit you will have reworked a charge jack plug within ? saves you stripping it down again to charge .. even a fly lead ?
You need to look at the board for jumper pins. I think you need to reset the board.
48:50 I was waiting when the ring makes contact with the batteries and start glowing red hot and leave 'nice' imprint in finger. I must say this guy is much braver than I. I would have taken ring off 'just in case'.
check the ic charging comparator it's like an ic that drive the MOSFET gate...
Killed it! Good work!
Great attempt, but from the getgo I was worried the selfdestructing electronics in these batteries would sabotage your attempt … Do you have any knowledge on the charging protocol/pinout of Milwaukee batteries ? Pins 1 and 5 are for discharging, but I’d love to balance charge my batteries with a CC/CV lab power supply. I think pin 3 is involved, but I wonder if anyone knows for sure … Since yours was defective, pin 3 may have been disabled.
Hold the button five seconds to reset board then put on charger then push button once more then remove from charger and the put back it should work
Ayr is also a town in Scotland that is about 20 mins from where I live.
hi i have 2 m28 milwaukee batteries that show 27 volts on the inner negative and the single positive but shows zero on the outer negative. and it shows flashing red green on charger and only one display light on .could i bridge the inner negative to the outer ?
You can't check batteries for shorts by beeping them out. And batteries are supposed to be shorted, which means they have a low internal resistance.
Nice video , BMS has tripped 👍👍👍👍 the cap could be 1uf 10 uf
Vince you are a very good man and again i loved that video so much❤️
I don't think this has been mentioned but have you tried to reset those 'dead' cells? A little known fact is that good quality 'branded' cells (like these 21700's) have a safety cut-off button under the positive end of the cell. It pops up when over-discharged and physically disconnects the positive end of the cell. As only some of those 15 cells appear 'dead' this may be the reason...so...IF and only IF a cell reads 0 (zero) volts then try to reset the cell.....here's how: (there are videos online of this if my explanation is rubbish)
A small jewellers screwdriver, although a plastic alternative would be much safer, can be used to 'push' the button back down toward the cell. Access is gained through those slits around the positive end. Insert the prying device of choice into one of those slits and gently push downward.....remembering that IF this does reset the cell it will instantly become 'live' again.
Best practice is to do this very gently in stages....measure the voltage after each atempt. It does not take much to reset. The button is very much like the metal contact under a push button switch....I know you know of these...I've seen you mend them, so you know how little force is required to move them. You probably won't actually feel anything move or click or even make a sound but go slowly and test after each try....if you get any voltage at all then at least the cell will be 'active' again.
No guarantee this is the problem but I've had laptop cells do this on a regular basis, some shut down others don't, just as you have here.
I hope you at least give it a go, what have you to lose? You may get a few cells back....just be carefull, common sense, oh and remove your wedding ring if you're going to pat the top of a live circuit board. Stay safe.
Your voice is so soothing
had a similar problem i just jumped the wires to the leads around the board and there was voltage indicator on the battery that worked
Hi watch all your videos with great interest just to help you out a you tuber called Andy mechanic has previously done some videos on repairing milwaukee batteries and he had to replace the circuit board after he replaced the damaged cells in the battery. Keep up the fantastic educational videos.
That was a great repair, Vince. Not quite what you wanted, but nonetheless it is working. 👍👍👍👍
What a great video, I know its just for entertainment but how interesting. My guess is that it has a bug in it but it wasn't the cause of the fault. To avoid infestation of service facilities its not unusual for companies to just refuse to repair anything with an insect in it. Just a thought. Anyways solid entertainment! Cheers!
Thanks Roger 👍👍👍
Those 18650 cells does have an internal fuse against overcharge, the temperature raises too much It cuts off. You'll ser they have 0 volts. You can get around that putting It on a vice and pressing the plus nipple a little bit so it closes the circuit again. It's dangerous though, it's safer and not expensive replacing those cells. You can be sure something went south with that BMS as It demanded so much current from one or more cell that it fried.
first of all those are 21700 batteries, and second no they dont ave any internal protections on them hence the reason they are prone to bursting into flames when they fail. he even pulls the spec sheet up on them in the video and you can clearly see where it says that there is NO protection on these cells
Why didn't you get a spot welder
Would be interesting if you bought one of the replacement charging PCBs from eBay and see if you could make it work with that. I sadly cant find the 12ah version but maybe take some cells out and make it a 9ah version because those PCBs are easy to find
The burn looked like it went from the contact the the closest IC contact... I wonder if that is a power or ground there! Maybe see about recovering a replacement board from another dead battery or online a replacement board?
Bug damage! Where does he live, Klendathu?
vince now you have met the proper company get them to sponsor you
18650 batteries have built in safety in case of overcharging/short circuit where a thin disc on the positive terminal ‘pops’ up and renders the battery useless. These can be reset Vince. Look into it and you’ll be surprised what u find 😉
Have you traded on the Milwaukee charger again yet because since you got the voltage that it needs back into the battery the charger is looking for above 16 V to charge the battery the Milwaukee charger might work now
You may call me crazy, but there was a hack to revive Ryobi LiIon battery, once it dropped below the threshold where the charger would think it was broken. Basically, you'd take a 12v battery charger, set to the 2ah setting and for just a second, tap the positive and negative. It would temp charge the cells to a high enough voltage to go above the threshold and allow to charge normally. Just editing to clarify, you'd tap the charger leads to the battery pack buss positive and negative, not individual cells.
Excellent video my friend! 👍😊
The board is about £5 on eBay. As far as I can tell ..
Peace and love brother 👍🏻☮♥️
Jesus loves you
I could be mistaken, but only the Fuel line of tools has to communicate with the battery.
You can bump charge them to initiate the ability for a charger to commence a charge cycle . I use a Rc charger for this .
Make sure that you keep an eye for heaters ( any heaters remove and discharge / recycle )
But you will be surprised how many cells will work and be close to there full capacity and reusable - allows to sit for 4 weeks to see it they have internal shorts and use common sense !!! Ie do all this outside in a shed @ you own risk