I have three of these chargers and packs - just a little over a year and a half old. I can confirm that they pull down while on charge. I leave them plugged in and on charge in my garage at all times when not in use and do not shelf them. Rather than keeping the batteries charged and maintaining them, the chargers do not seem to handle babysitting well. I came out for the first mow this spring, and the charging lights on all three chargers were off, and all three battery packs are measuring 0 volts. After much research - and trying boosting - I came across your video. This is absolutely wonderful content and I thank you for this thorough tutorial.
It is absolutely as simple as he says. The battery would not get any charge- I used my 12V battery charger- think I bought it for $12.95 at the Auto Zone ..for literally 5 minutes, and now it is charging on the station! Thanks!! The acid test will be if it will run the blower.... I am very pleased. Off to Wing Haus!
I know it’s a long shot but I need some help where I can get it. I have the exact same product. I have wired two 18 volt Milwaukee batteries in series to make 40v and attached them to the kobalt battery for several hours and still the battery will only read 9 volts no matter how long it is hooked up. The charger does nothing when I put the battery on it UNLESS I connect a 40v supply to the positive and negative while the battery is charging. If I do that it will flash green like it’s charging for about 30 seconds and then flash red. The battery looks perfect inside. Does anyone have any ideas?
I have mentioned in many videos to caution putting a non current limited supply across packs without knowing the packs condition. What do the individual cells read across them? How well are the cells balanced? Is the fuse still ok after putting a 40V supply across a discharged pack without current limited properly? Absolutely make sure the cells in the pack don't look like the cells in the second pack shown in this video.
@@ThriftyToolShed I identified one cell that bounced around only showing a few mV. I am assuming that was the cause of the pack not taking charge. I most likely won’t go any further as it’s not worth it to buy a new cell. All the other cells were between 2.4-3.1
I have a 40v 5ah and it is sitting at 23 volts. Charger light wont come on. I tried this and still nothing. Visually the cells look good when i took it apart. Any suggestions?
I would check cells individually and make sure they are balanced. You may have some that have dropped down lower than others. If that is the case, it is typically bad cells as the capacity has most likely diminished in these cells, and they are dropping off faster than the others. You can try charging those up to the same level as the others to get the pack balanced well and try that. If the cells are bad they may not charge up at all. So monitor at all times to make sure they are not overheating. Even if they do charge up if they have lost capacity they will eventually drop off, and this condition will repeat. If by chance they are all balance, but all around 2.3V each then the pack may have to be boosted up a bit to get it to accept a charge. So setting a PS to 30V and Current limit to around 1 Amp or so slowly bring the pack up to around 30V and the charger may then charge it up. Best of luck to ya!
This was an absolutely great video for DIY'ers. I got a lot from this video as I have looked for one breaking a Kobalt down and explaining it. Thank you for the video. Would love to see a, "replacing cells" video. I have one that is throwing the red light yet still gets two green lights on the display. Would love to fix it.
I do have some EGO pack repair videos as well. A few with BMS type issues and a couple with cells replaced. I have only worked on this one set of Kobalts so far.... Thanks for your comment!
Really Great Video. I was dubious of these boost videos too but after watching your I decided to try. I opened my 4.2V no-charge 40V pack up and found the cells to be in visually good condition. I boosted the pack with a 12V-2A charger for maybe 30s and dropped it in the Kobalt charger where it got a flashing charge light again. I came back latter and all the cells registered between 4.13V-4.16V. I will comment again if I find the pack failing again soon.
hello i have a 40v kobalt pressure washer but i dont have the battery.. i have other 10 cell battery pack i want to wire to the power washer but the power washer has 3 wires.. red,black and a blue wire.. i have no clue what to do with the blue wire.. the power washer works with just red and black wire connected.. but only stays on for 5 sec and shuts off
I did not go very deep on these packs with the wiring or pinout. It's been years ago since I have given these packs back to a friend. These simply had cell issues. I have no packs like this at the moment. The common practice on simpler pack designs is to have a NTC thermistor monitoring the pack and feeding back to the tool for a temperature reference. Some of these are around 10K ohm at room temp. This is not the case for all packs, but it's possibly similar. I shared a little bit about the 3rd pin on a 20V Bauer flashlight some years ago. It May not be the same, but it's all I really have on video besides some Ego packs repairs. You might find it helpful. ruclips.net/video/IJ-xZ0zdwbo/видео.html
Great video, thank you. My battery has a full set of lights indicating full, it shows 40.?? Volts but the light on the charger is out. Could it simply be the light is bad or something more sinister?
I guess you are saying with a meter you are reading 40V on the battery terminals? I would check connectors on the pack and the charger itself to make sure connections are clean and making a good connection. These chargers don't light up until it senses the pack in place. If that does not fix it it's time to swap batteries or charger to eliminate which is the issue.
Great video! Perhaps you can help me. I have a Snapper 60V weed eater. The charger (like yours) starts out with a flashing green and after a few minutes goes red. upon pack inspection, batteries appear undamaged and read 41.9V on the meter. The pack display lights do not come on when I press the button. When placed in the weed eater it does not function. I would guess at 41.9V I do not need to give the pack a jump. What gives?
If you check across individual cells you may see a obvious cell lower than the others. Typically 1 or more cells are bad with your description. If all are balanced well then it may not be charging if voltage is still low on all cells equally.Best of luck!
@@ThriftyToolShed Well I did as you suggested. The pack has 15 (3.7V) batteries. ten read 3.5V, three read 3.4V and two read 0V. So if I replace the two dead ones I should be able to charge them? Also I am not sure what the size of the batteries are. Thanks again for your help. PS when I check the voltage from the charge prongs it now reads 42.7V
I have a question what would I look for when it comes to (70vand below)overcharging batteries and why would the battery is not show up as full understanding there is probably more to this question that I don't know to ask
Are you saying the battery is overcharging? Overcharging lithium cells cans be very hazardous. Could cause fire or small explosion. Over charge and over discharge is both something to watch out for with lithium cells. So typical specs for Li-ion cells is no lower than 2.7V and no higher than 4.2V. lithium is a amazing battery platform, but it is not tolerant of out of spec charge/discharge levels or high temperature.
@@ThriftyToolShed I have start off by saying thank you for the concerned reply and I completely understand the dangers that come with lithium batteries . The reason for my is to find out what direction I should possibly go towards fixing this issue with the batteries overcharge . Note. The batteries have not lost any charge in any of the 5 battery packs but all are to high (obviously)
I really have never had an issue with a pack being overcharged by a charger. I guess so many checks and safeties in this is most likely to fail non working than over doing it. With that said, I realize how it is still possible. I would think the charger is the cause of this issue. The charger should always monitor the pack before starting charge and of course while charging to make sure no unsafe condition and that the cells do not go over 4.2v each. Have you tried more than one charger or battery pack or do you only have the one of each?
@@ThriftyToolShed I have 5 batteries and two chargers only 1 of the battery lights....light up completely and the others either don't light up up for only have a single light. In regards to the charges I have not had a chance to test them sufficiently oh and before I had check the voltages of the batteries with a voltmeter I tried charging them first(I know rookie mistake) and all the batteries except one eventually flashed red(with no real order to how I charged them)
So all 5 are higher than the 42V charged on the 49V packs? And only one shows fully charged by indicator lights the other 4 show either none or just 1 LED? Well I am not sure about that, but the charger is most likely bad if over charging. I can not remember if there packs have a reset on the boards. I have a video on the Echo 58V pack that I repair and I showed briefly that jumping Reset to Ground on the board will in rare cases help with battery level issues by resetiing the microcontroller. That is all I would know to look and try from here, I only worked on these 2 packs shown in video, other than that, I have no other knowledge of issues to share. That reset may be a long shot..
Not that it could not be done. You could rig up a 40V power supply or take a larger supply and use a buck regulators set to around 45V or so and it would be fine. To me that is the wrong direction, the batteries give so much freedom that I would be more inclined to use the pack connectors for another battery adapter or two 20V packs in series to run the device in a tight! I mentioned this on my 40V Ryobi video. It worked well. Just my thoughts!
Yeah, I bought a used set with 2 bad battery packs. Bought a new battery and it just doesn’t have enough juice to get through my back yard. I’m not super electricity inclined so I’ll probably buy another battery pack or figure out how to get into the broken ones. Screw heads are stripped I guess the guy before me tried getting in them. Thanks and awesome video
Good information, even if over a couple years old. Just as a note. The 40V 5amp Kobalt battery pack has a 60amp fuse, not the 40amp the smaller 2.5amp pack has. So if you had another roll of batteries you need to upgrade the fuse, since you are in essence increasing the amperage not the current.
Thanks for your comment. Yes the fuse would have to be changed. You could get by on some tools like weed eaters and such that would not pull more load anyway just because of more capability to do so of course. But in heavier load devices that could possibly pull more current when available yes the fuse would absolutely have to be increased. Basically putting 2 cells in parallel is giving the ability to output up to twice the current. Most tools should not demand more than 40 amps more than a few seconds really unless something is wrong. Btw: Amperage is Current so it's the same thing.
Typically they are 18650 form factor, and for the 2.0 AH battery the cells would be 2000 mAH capacity. With 4V per cell, there would be ten cells stacked in series. For 5.0 AH, that battery might have cells in parallel and those sets of parallel cells get stacked in series to reach the 40V total voltage. Open it up when it goes bad to confirm. That’s my guess - I don’t own this type of battery.
I will if I come across a pack like that again. I repaired those for a friend for there Church. Other than that I have not had any Kobalt 40V. Thanks for your comment!
@@ThriftyToolShed i have quite a few of these. I have a 4ah that is going bad and some 2ah that i would like to be made into 4ah. If you would be interested.
I inherited one of these that didn't work. The small 3.1A fuse on the ACV side is blown. I had a 5A fuse available and soldered that onto the pcb see what would happen. With no battery on the charger, it immediately blew that fuse the moment it was plugged in. Thoughts?
I have not had any issues with the chargers for these yet to say. I have had similar issues with similar chargers. I would check the rectifying diodes (bridge) and the switcher.
Thrifty Tool Shed Well I did as you suggested. The pack has 15 (3.7V) batteries. ten read 3.5V, three read 3.4V and two read 0V. So if I replace the two dead ones I should be able to charge them? Also I am not sure what the size of the batteries are. Thanks again for your help. PS when I check the voltage from the charge prongs it now reads 42.7V
Yes, sometimes if the cells have no part number or info to look up the spec sheet from. All I do at that point is get as close as possible with the pack rating. For example 60v pack with 15 cells you know the mAh rating of the pack is the rating of each individual cell in series! So a 2.0 ah pack will or should have 2000mah cells. 👍
Nice production work and on target with info I was looking for. Thanks. Would like to know how to adapt the Kobalt charger to a 38v pack for a scooter project in the near future.
I do not still have this Kobalt charger since I worked on these for a friend. I can't recall exactly how the charger worked on these. Most will atleast have a temp monitoring terminal feedback from pack to charger that should have Thermistor. I discuss similar connections I'm a DeWalt video I have as well as a an EGO pack video called "what is the T-terminal" I mention something really similar in a 20V LED Light video as well. May not be hard to do, but some like EGO, the chargers actually communicate with the pack and that makes it almost impossible. Thanks for your comment!
Your best bet is to use the packs from Kobalt as-is on the scooter. Just be sure that you have under voltage protection on the motor controller. All outdoor power equipment batteries (basically ones from 40-80v) have battery mgmt on the packs vs the 12-20v power tool packs which have more of the “balancing” system on the charger.
The quick answer is No most packs you could boost without opening however, the point of my videos is you don't know what condition your pack is in if you don't open it up. I personally open packs up do a visual and one of the most important to me is check the individual cells voltage level. If you notice a cell that has gone really low voltage level they usually past the point of saving, at least the capacity is severly reduced. Even if you are successful boosting a cell that was below say 2 volts it will not hold up long under load.
My 40v max 4.0 an Battery is not charging if I push 😅the check button all 4 lights blink. With the charger plugged in the light on it will not light up.
I have 3 packs, 2 show 41V and full charge, 1 36 volts and 50% charge. I missed where the LiOn cell voltage increased from 3.3 to 4?? Any way, the half charged unit reports bad.. I can't detect any change in pack voltage while the charger is in the flashing green mode.. prior to it switching to red.. Charger test points tp5/tp6 idle at 18v and when a full charge unit is plugged in it is still at 18v. but when the 'half charged unit is attached the voltage at across tp5/tp6 goes to pack voltage while the led be blinking green. when the led goes to red, the voltage on tp5/tp6 goes to the 18v idle value. I can't id the Q11 M60130 device
I don't still have these packs, they were given back to a friend over a year ago. I do not own any myself or I would look up the Q11 and see if it's the same number. As far as the cells back to 4V, I used my bench power supply and brought the individual cells up set at 4V and Current limit are 1A until all were good.
I have a question on an 40 volt Oregon chainsaw battery pack. I checked the voltage and it is reading 40 volts and shows four green lights on the front of the pack but it has no current. I put it on a brand new Oregon charger. I have no history on the pack because it is a customers saw. I left it on the charger overnight to see what would happen. I know the saw is not the problem because I put the battery on the charger for 30 minutes and when plugged into the saw, it turned the saw over for a second or so. It wurst have a hell of an internal resistance. My recommendation was to replace the battery pack. You thoughts?
I have rarely seen a 40V Li-ion pack show full voltage and drop off that quick. Used to be common with the old ni-cd packs. I would try to connect with jumpers etc. Out of the saw or another load if possible so you can check the pack voltage under load. It could be a bad cells that drops off quick. It could even be a bad connection to one of the cells in the pack like the spot weld connection or so. It is very rare. I am not familiar with the oregon saw but some tools will shutdown if it thinks the pack is too low or over temp. etc. So some communicate with the pack and could shutdown based on an issue and in that case it is hard to be for sure it is truly the pack, I would say 90% of the time it is a pack issue! Wish I could help more, I would load test the pack at least! Best of luck to ya!
@@ThriftyToolShed I put a VOM to the battery pack and it said 40 VDC and the test button shows four green bars. That is why my saws are Stihl two cycle. You just cannot depend on battery crap. I do have one pole saw that is lithium ion and several drills and impacts, but I leave them on their chargers when not in use, just like my laptop and tablets.
@@johnclarke6647 I am the opposite, I have always had nice gas saws but now I have a 14" and a 16" EGO and my chains have just rusted on my gas saws. I would as with any saw have more than one and of course I have 5 or so bought packs and about 10 repaired ones. Gas or battery I never go into the woods without back-up. I have not needed it yet with my EGO. But I still have it if I get it pinched or if a saw fails on me. It will still be a little while before the mass is ready for battery powered saws completely but hopefully when the solid state batteries platform arrives with in the next 5 years or so hopefully that will be when battery will over take gas! Hard to compete with the power density of gasoline but since the efficiency is less than 30% with gas due to most of the energy it produces is heat. We are close....
@@ThriftyToolShed iave a couple of 16 inch saws but most of mine are the big Stihl saws, many of whom I built. I will bet those little saws will not stay with my ms 460, 440 or for the real big stuff my ms 660 and it’s 28 inch bar. Either of these saws will make your battery operated saws look like a kids toy, which is what they are. They are ok around the house but when you have to fell and buck up 25 inch hardwood they are sadly lacking.
We actually had a small engine repair shop before my Dad retired a few years back. We did a tremendous amount of saw sales and service for loggers ( I simply helped him at the start and part time when I had time) so I am not ignorant by any means on the big boys, I was talking about mine and mine alone. I have never needed a big saw for my own personal use. I only used them back then while testing the repairs for the loggers. I do remember the older McCullough 850 before the Husqvarna and Jonsered turbos were a pain to keep pulling on when you are learning to work on them, rough on the elbow. Lol. I would never compare my $200 EGO to that or my even my decent Echo 21" gas saws either. They are not even on the same spectrum. Glad I have never needed that much saw around my house.
I'm looking to build a 5ah pack out of two of these (as optionally sold). Any clue how to wire and if the BMS/charger would work in this configuration?
I do not have these any longer since I gave them back to a friend but the best I can remember, the BMS wires are good to go and putting the cells in may all you need to do. You will have to get the pack halves separated to install but by memory everthing else is fine because the added cell is just parallel! Hope it helps
@PussMag Great to know, it may be a resistor on board to let the charger and tool know which pack is connected then? Interesting! If I come across another one of these, I will have to look at it better....
Note that these type of packs often have configuration jumpers or different firmware based on the specific cells (2.0, 2.5, 3.0) and cell counts (1p, 2p, etc).
I am sure different packs manufacturing at different times are not all the same but they are 18650 li-ion cells with the rating of your pack. For example if you have a 2.0ah pack, the cells are 2000mah rating...
Heyo, thanks so much for the disassembly and info. Currently in the process of fixing up one of these 5.0Ah versions, and discovered two cells had gone completely flat (0.0V) and acted as a break in the circuit despite the spot welds being flawless. So I just took them out and swapped in similar 2500mAh 18650s I had from another battery. My question is does the on board charging circuitry balance the cells while charging or does it only apply a consistent 41/42V across the entire series for charging? That way I know for the future if for some reason the replaced cells or some other ones go bad and I need to swap in with cells that may not have the same internal resistance (i.e. go out of balance easier during discharge)
Hi, Thanks for your comment. I do not know exactly when the balancing takes place and I am not sure of how much it can correct. I have never had to look into the balancing that close. I do try to match my replacement cells internal resistance and capacity with the pack as close as possible to help with any imbalance issues. I have always thought the pack gets balanced while charging? That may not be exact, just my initial thoughts about the BMS. Best of luck to ya on that repair!
Nice Video - thanks for posting.. So I have a Large Capacity 4.0Ah Kobalt Battery - it still seems to work in my garden tools. When I charge it also works for a while, but ultimately the charger light blinks red indicating a charging fault. I've tested the voltage of the battery after the charging fault, and it reads 37.7 volts. I haven't yet opened it up. Any guess on this one? Maybe a bad cell in there so it can't quite reach the max capacity?
Thanks for your kind comment! Yes more than likely it's a cell or possibly more than one that has lost capacity. With cells in series one cells greatly affect the others. When pulled down low it can be lower than others causing an early shutdown for the pack and can also cause issue when charging because it will still be low when others get to the full 4.2v max. I would run the pack down to cut off point and then check if some cells are much lower in voltage than others.
@@ThriftyToolShed - BTW - would you expect these higher capacity batteries to be more prone to overheating and defects? I have 2 of the 2.0Ah ones and they seem fine. All of these were purchased a while back - circa 2015
Sometimes it does seem that way. More cells Inside, so more that can go wrong even though they can handle more current than the smaller ah packs so they are typically better for heavy loads such as blowers and mowers.
one last silly question, how in the world do you get the cells separated from the little rivets on the top and bottom of each cell.? I do not want to tear this up. The cells are hard to remove from the plastic housing!
I am not sure how your particular battery is however most I have seen are similar, I have a couple videos that I do show removing cells from the EGO 56V pack and Ryobi 18V pack you may find helpful. You have to carefully pry the tabs off and when you reattach the new cells you have to either spot weld tabs back or carefully solder the tabs back which I do show in the videos. Hope it helps!
Do you jump it on the "C" terminal? I tried to charge mine through the positive and negative leads with no success. Just curious if the positve lead should be connected to the c terminal. Thanks!
No, you should not have to jump. + And - are going to cells directly. The only thing in between is the fuse! Other than that could be open cell or connection?
I have come across one of the mowers with this particular battery unit on it but it's a six amp hour and I have experience working with these style battery packs and I've had this one apart it's got 20 batteries in it 20 individuals but I'm not too impressed with the way it's laid out because what I found out so far is is it uses 10 batteries per I want to say per 20 volts and they double on each end of the pack you have a 20 volt set and another 21 set and then they run the two sets in series to get 40 volts but I don't see why this thing has so many issues it should do really well and even more powerful than I would think but my Craftsman v20 batteries at 4 amp hours seem way better than this and more dependable and I can leave them on charge and they care for themselves or take them off and they don't have many issues but I'm considering building an adapter to run my Craftsman batteries in series to use this mower because The run time on the battery I have when I first come across it was charged fully and ran good but they don't seem to want to take a good charge now so if the charger I get doesn't work right and the batteries don't work right I'm going to work on an adapter run the batteries I'm going to buy and the charger in the ground and switch it to the v20 batteries I think I'll do better they seem more dependable
I'm having trouble with an 80V max 5ah, it charges no problem there "apparently" tested its voltage it registered 79 when I put it on my mower it lasts less than 20 minutes. Going crazy and they're expensive, when I put it in the charger no issues all green lights. Any ideas anyone?
If you do have more than one pack it is helpful to make sure the charger is charging correctly. The next step would be to open the pack up (if not still under warranty that is) and test all cells to make sure they are all balanced and that one or more have not lost capacity. When a pack gets older it is possible most of them have lost capacity, but unusual with in a few years of use. I have not worked on the 80V myself, but the 5ah@80v means most likely 40 cells packed tight in that housing. That will not be fun to work on. Unless they used 5000mah cells and did 1P 20s. Alot of packs use 2500mah cells and 2p for the 5ah rating so 20s would be 40 cells?
I had a Greenworks 80 volt. After watching this video, I tested my volts and saw 63. That left me believing I had a similar issue, so I pulse jumped it for about an amp. It woke up the charging system. It then accepted normal charge again from the Greenworks charger.
Sunny Rey I have greenworks stuff. It’s the same as Kobalt. The battery does tend to get stuck. Generally pressing the release button and giving the unit a tap or two will release the battery. Obviously use extreme caution with any tool, especially a chainsaw.
First Kobalt 40v battery (for hedger) died after a year, so free exchange with Lowes. New one lasted about 1.5 years, now it's dead. $80 to replace. I don't like these batteries.
I am working on one right now that is the same way. It had a couple reading close to zero and some others just above 1V while a few were up around 3v and tested with pretty good capacity. So all cells are needing to be replaced. Good thing is that the pack otherwise is in great shape and maybe a good candidate to increase capacity since it was only a 2ah pack and I think I have enough cells to double up and go close to 4ah. It is not always worth the cell cost to rebuild these, but I have some from another salvaged pack and I want to try to make use of the unused cell locations and make it a 2P just to see how well it works.
These batteries/devices are horrible... there is no logic in the devices to NOT run the battery completely dead... so.. I have to use a trickle charger connected to blades that fit the battery... for about 5 minutes... then charger works... problem stems from the charger requiring it to detect a small voltage reading before it will turn on.
I just bought a new 80v 6 amp max cobalt mower and the batt is prob twice the size of those but have a fan in them. They are obviously making improvements as they go.
I have three of these chargers and packs - just a little over a year and a half old. I can confirm that they pull down while on charge. I leave them plugged in and on charge in my garage at all times when not in use and do not shelf them. Rather than keeping the batteries charged and maintaining them, the chargers do not seem to handle babysitting well. I came out for the first mow this spring, and the charging lights on all three chargers were off, and all three battery packs are measuring 0 volts. After much research - and trying boosting - I came across your video. This is absolutely wonderful content and I thank you for this thorough tutorial.
Don’t leave batteries on chargers. It is never a good idea and often a bad idea. Sometimes it could be very bad and cause a fire.
no wonder its 0 volts you are abusing them
@sa
Great video! Thanks for the time to make it and explain everything so even beginners like me can understand. It is appreciated!
It is absolutely as simple as he says. The battery would not get any charge- I used my 12V battery charger- think I bought it for $12.95 at the Auto Zone ..for literally 5 minutes, and now it is charging on the station! Thanks!! The acid test will be if it will run the blower.... I am very pleased. Off to Wing Haus!
I know it’s a long shot but I need some help where I can get it. I have the exact same product. I have wired two 18 volt Milwaukee batteries in series to make 40v and attached them to the kobalt battery for several hours and still the battery will only read 9 volts no matter how long it is hooked up. The charger does nothing when I put the battery on it UNLESS I connect a 40v supply to the positive and negative while the battery is charging. If I do that it will flash green like it’s charging for about 30 seconds and then flash red. The battery looks perfect inside. Does anyone have any ideas?
I have mentioned in many videos to caution putting a non current limited supply across packs without knowing the packs condition. What do the individual cells read across them? How well are the cells balanced? Is the fuse still ok after putting a 40V supply across a discharged pack without current limited properly? Absolutely make sure the cells in the pack don't look like the cells in the second pack shown in this video.
@@ThriftyToolShed I identified one cell that bounced around only showing a few mV. I am assuming that was the cause of the pack not taking charge. I most likely won’t go any further as it’s not worth it to buy a new cell. All the other cells were between 2.4-3.1
@@PHV1969 Sounds like it's that one for sure.
I have a 40v 5ah and it is sitting at 23 volts. Charger light wont come on. I tried this and still nothing. Visually the cells look good when i took it apart. Any suggestions?
I would check cells individually and make sure they are balanced. You may have some that have dropped down lower than others. If that is the case, it is typically bad cells as the capacity has most likely diminished in these cells, and they are dropping off faster than the others. You can try charging those up to the same level as the others to get the pack balanced well and try that. If the cells are bad they may not charge up at all. So monitor at all times to make sure they are not overheating. Even if they do charge up if they have lost capacity they will eventually drop off, and this condition will repeat. If by chance they are all balance, but all around 2.3V each then the pack may have to be boosted up a bit to get it to accept a charge. So setting a PS to 30V and Current limit to around 1 Amp or so slowly bring the pack up to around 30V and the charger may then charge it up. Best of luck to ya!
what's the discharge rate on these?
This was an absolutely great video for DIY'ers. I got a lot from this video as I have looked for one breaking a Kobalt down and explaining it. Thank you for the video. Would love to see a, "replacing cells" video. I have one that is throwing the red light yet still gets two green lights on the display. Would love to fix it.
I do have some EGO pack repair videos as well. A few with BMS type issues and a couple with cells replaced. I have only worked on this one set of Kobalts so far....
Thanks for your comment!
Really Great Video. I was dubious of these boost videos too but after watching your I decided to try. I opened my 4.2V no-charge 40V pack up and found the cells to be in visually good condition. I boosted the pack with a 12V-2A charger for maybe 30s and dropped it in the Kobalt charger where it got a flashing charge light again. I came back latter and all the cells registered between 4.13V-4.16V. I will comment again if I find the pack failing again soon.
Awesome, thanks for sharing!
hello i have a 40v kobalt pressure washer but i dont have the battery.. i have other 10 cell battery pack i want to wire to the power washer but the power washer has 3 wires.. red,black and a blue wire.. i have no clue what to do with the blue wire.. the power washer works with just red and black wire connected.. but only stays on for 5 sec and shuts off
I did not go very deep on these packs with the wiring or pinout. It's been years ago since I have given these packs back to a friend. These simply had cell issues. I have no packs like this at the moment. The common practice on simpler pack designs is to have a NTC thermistor monitoring the pack and feeding back to the tool for a temperature reference. Some of these are around 10K ohm at room temp. This is not the case for all packs, but it's possibly similar.
I shared a little bit about the 3rd pin on a 20V Bauer flashlight some years ago. It May not be the same, but it's all I really have on video besides some Ego packs repairs. You might find it helpful.
ruclips.net/video/IJ-xZ0zdwbo/видео.html
Great video, thank you. My battery has a full set of lights indicating full, it shows 40.?? Volts but the light on the charger is out. Could it simply be the light is bad or something more sinister?
I guess you are saying with a meter you are reading 40V on the battery terminals? I would check connectors on the pack and the charger itself to make sure connections are clean and making a good connection. These chargers don't light up until it senses the pack in place. If that does not fix it it's time to swap batteries or charger to eliminate which is the issue.
@@ThriftyToolShed many thanks I’ll clean the terminals and see if that fixes it.
Hey Mr Thrifty... Are the 40v kobalt batteries 21700 cells?
Hi, I am not sure about some of the newer models. These older models as shown in the video are 18650 cells.
Great video! Perhaps you can help me. I have a Snapper 60V weed eater. The charger (like yours) starts out with a flashing green and after a few minutes goes red. upon pack inspection, batteries appear undamaged and read 41.9V on the meter. The pack display lights do not come on when I press the button. When placed in the weed eater it does not function. I would guess at 41.9V I do not need to give the pack a jump. What gives?
If you check across individual cells you may see a obvious cell lower than the others. Typically 1 or more cells are bad with your description. If all are balanced well then it may not be charging if voltage is still low on all cells equally.Best of luck!
@@ThriftyToolShed thanks so much I will check
@@ThriftyToolShed Well I did as you suggested. The pack has 15 (3.7V) batteries. ten read 3.5V, three read 3.4V and two read 0V. So if I replace the two dead ones I should be able to charge them? Also I am not sure what the size of the batteries are. Thanks again for your help. PS when I check the voltage from the charge prongs it now reads 42.7V
I have a question what would I look for when it comes to (70vand below)overcharging batteries and why would the battery is not show up as full understanding there is probably more to this question that I don't know to ask
Are you saying the battery is overcharging? Overcharging lithium cells cans be very hazardous. Could cause fire or small explosion. Over charge and over discharge is both something to watch out for with lithium cells. So typical specs for Li-ion cells is no lower than 2.7V and no higher than 4.2V. lithium is a amazing battery platform, but it is not tolerant of out of spec charge/discharge levels or high temperature.
@@ThriftyToolShed I have start off by saying thank you for the concerned reply and I completely understand the dangers that come with lithium batteries . The reason for my is to find out what direction I should possibly go towards fixing this issue with the batteries overcharge . Note. The batteries have not lost any charge in any of the 5 battery packs but all are to high (obviously)
I really have never had an issue with a pack being overcharged by a charger. I guess so many checks and safeties in this is most likely to fail non working than over doing it. With that said, I realize how it is still possible. I would think the charger is the cause of this issue. The charger should always monitor the pack before starting charge and of course while charging to make sure no unsafe condition and that the cells do not go over 4.2v each. Have you tried more than one charger or battery pack or do you only have the one of each?
@@ThriftyToolShed I have 5 batteries and two chargers only 1 of the battery lights....light up completely and the others either don't light up up for only have a single light. In regards to the charges I have not had a chance to test them sufficiently oh and before I had check the voltages of the batteries with a voltmeter I tried charging them first(I know rookie mistake) and all the batteries except one eventually flashed red(with no real order to how I charged them)
So all 5 are higher than the 42V charged on the 49V packs? And only one shows fully charged by indicator lights the other 4 show either none or just 1 LED? Well I am not sure about that, but the charger is most likely bad if over charging. I can not remember if there packs have a reset on the boards. I have a video on the Echo 58V pack that I repair and I showed briefly that jumping Reset to Ground on the board will in rare cases help with battery level issues by resetiing the microcontroller. That is all I would know to look and try from here, I only worked on these 2 packs shown in video, other than that, I have no other knowledge of issues to share. That reset may be a long shot..
Anyway to take a broken battery pack and make it a plug-in extension cord?
Not that it could not be done. You could rig up a 40V power supply or take a larger supply and use a buck regulators set to around 45V or so and it would be fine. To me that is the wrong direction, the batteries give so much freedom that I would be more inclined to use the pack connectors for another battery adapter or two 20V packs in series to run the device in a tight! I mentioned this on my 40V Ryobi video. It worked well. Just my thoughts!
Yeah, I bought a used set with 2 bad battery packs. Bought a new battery and it just doesn’t have enough juice to get through my back yard. I’m not super electricity inclined so I’ll probably buy another battery pack or figure out how to get into the broken ones. Screw heads are stripped I guess the guy before me tried getting in them. Thanks and awesome video
Good information, even if over a couple years old. Just as a note. The 40V 5amp Kobalt battery pack has a 60amp fuse, not the 40amp the smaller 2.5amp pack has. So if you had another roll of batteries you need to upgrade the fuse, since you are in essence increasing the amperage not the current.
Thanks for your comment. Yes the fuse would have to be changed. You could get by on some tools like weed eaters and such that would not pull more load anyway just because of more capability to do so of course. But in heavier load devices that could possibly pull more current when available yes the fuse would absolutely have to be increased. Basically putting 2 cells in parallel is giving the ability to output up to twice the current. Most tools should not demand more than 40 amps more than a few seconds really unless something is wrong. Btw: Amperage is Current so it's the same thing.
@@ThriftyToolShed agreed. I meant to say voltage not current doh!
What cells are used inside of these Kobalt packs?
I would like to know as well, as least the size/volt/amp so I can upgrade my 2.0 and repair my 5.0 amp in the future when it goes bad.
Typically they are 18650 form factor, and for the 2.0 AH battery the cells would be 2000 mAH capacity. With 4V per cell, there would be ten cells stacked in series.
For 5.0 AH, that battery might have cells in parallel and those sets of parallel cells get stacked in series to reach the 40V total voltage. Open it up when it goes bad to confirm. That’s my guess - I don’t own this type of battery.
Yes, this is correct for this pack!
Could you make a video of how to add more cells?
I will if I come across a pack like that again. I repaired those for a friend for there Church. Other than that I have not had any Kobalt 40V. Thanks for your comment!
@@ThriftyToolShed i have quite a few of these. I have a 4ah that is going bad and some 2ah that i would like to be made into 4ah. If you would be interested.
My pack will not light up and I don’t understand how you go yours to light when it would not
I tested the cells and they were very low. I had to charge the cells up slowly with my Bench Top Constant Current power supply.
I inherited one of these that didn't work. The small 3.1A fuse on the ACV side is blown. I had a 5A fuse available and soldered that onto the pcb see what would happen. With no battery on the charger, it immediately blew that fuse the moment it was plugged in. Thoughts?
I have not had any issues with the chargers for these yet to say. I have had similar issues with similar chargers. I would check the rectifying diodes (bridge) and the switcher.
Thrifty Tool Shed Well I did as you suggested. The pack has 15 (3.7V) batteries. ten read 3.5V, three read 3.4V and two read 0V. So if I replace the two dead ones I should be able to charge them? Also I am not sure what the size of the batteries are. Thanks again for your help. PS when I check the voltage from the charge prongs it now reads 42.7V
Yes, sometimes if the cells have no part number or info to look up the spec sheet from. All I do at that point is get as close as possible with the pack rating. For example 60v pack with 15 cells you know the mAh rating of the pack is the rating of each individual cell in series! So a 2.0 ah pack will or should have 2000mah cells. 👍
Nice production work and on target with info I was looking for. Thanks. Would like to know how to adapt the Kobalt charger to a 38v pack for a scooter project in the near future.
I do not still have this Kobalt charger since I worked on these for a friend. I can't recall exactly how the charger worked on these. Most will atleast have a temp monitoring terminal feedback from pack to charger that should have Thermistor. I discuss similar connections I'm a DeWalt video I have as well as a an EGO pack video called "what is the T-terminal" I mention something really similar in a 20V LED Light video as well. May not be hard to do, but some like EGO, the chargers actually communicate with the pack and that makes it almost impossible. Thanks for your comment!
Your best bet is to use the packs from Kobalt as-is on the scooter. Just be sure that you have under voltage protection on the motor controller. All outdoor power equipment batteries (basically ones from 40-80v) have battery mgmt on the packs vs the 12-20v power tool packs which have more of the “balancing” system on the charger.
very comprehensive video....thank you. I did not quite understand how to boost the battery? Do I need to open up the battery to boost it?
The quick answer is No most packs you could boost without opening however, the point of my videos is you don't know what condition your pack is in if you don't open it up. I personally open packs up do a visual and one of the most important to me is check the individual cells voltage level. If you notice a cell that has gone really low voltage level they usually past the point of saving, at least the capacity is severly reduced. Even if you are successful boosting a cell that was below say 2 volts it will not hold up long under load.
My 40v max 4.0 an Battery is not charging if I push 😅the check button all 4 lights blink. With the charger plugged in the light on it will not light up.
I have 3 packs, 2 show 41V and full charge, 1 36 volts and 50% charge. I missed where the LiOn cell voltage increased from 3.3 to 4?? Any way, the half charged unit reports bad.. I can't detect any change in pack voltage while the charger is in the flashing green mode.. prior to it switching to red.. Charger test points tp5/tp6 idle at 18v and when a full charge unit is plugged in it is still at 18v. but when the 'half charged unit is attached the voltage at across tp5/tp6 goes to pack voltage while the led be blinking green. when the led goes to red, the voltage on tp5/tp6 goes to the 18v idle value. I can't id the Q11 M60130 device
I don't still have these packs, they were given back to a friend over a year ago. I do not own any myself or I would look up the Q11 and see if it's the same number. As far as the cells back to 4V, I used my bench power supply and brought the individual cells up set at 4V and Current limit are 1A until all were good.
Great video, great information.
I have a question on an 40 volt Oregon chainsaw battery pack. I checked the voltage and it is reading 40 volts and shows four green lights on the front of the pack but it has no current. I put it on a brand new Oregon charger. I have no history on the pack because it is a customers saw. I left it on the charger overnight to see what would happen. I know the saw is not the problem because I put the battery on the charger for 30 minutes and when plugged into the saw, it turned the saw over for a second or so. It wurst have a hell of an internal resistance. My recommendation was to replace the battery pack. You thoughts?
I have rarely seen a 40V Li-ion pack show full voltage and drop off that quick. Used to be common with the old ni-cd packs. I would try to connect with jumpers etc. Out of the saw or another load if possible so you can check the pack voltage under load. It could be a bad cells that drops off quick. It could even be a bad connection to one of the cells in the pack like the spot weld connection or so. It is very rare. I am not familiar with the oregon saw but some tools will shutdown if it thinks the pack is too low or over temp. etc. So some communicate with the pack and could shutdown based on an issue and in that case it is hard to be for sure it is truly the pack, I would say 90% of the time it is a pack issue! Wish I could help more, I would load test the pack at least! Best of luck to ya!
@@ThriftyToolShed I put a VOM to the battery pack and it said 40 VDC and the test button shows four green bars. That is why my saws are Stihl two cycle. You just cannot depend on battery crap. I do have one pole saw that is lithium ion and several drills and impacts, but I leave them on their chargers when not in use, just like my laptop and tablets.
@@johnclarke6647
I am the opposite, I have always had nice gas saws but now I have a 14" and a 16" EGO and my chains have just rusted on my gas saws. I would as with any saw have more than one and of course I have 5 or so bought packs and about 10 repaired ones.
Gas or battery I never go into the woods without back-up. I have not needed it yet with my EGO. But I still have it if I get it pinched or if a saw fails on me. It will still be a little while before the mass is ready for battery powered saws completely but hopefully when the solid state batteries platform arrives with in the next 5 years or so hopefully that will be when battery will over take gas! Hard to compete with the power density of gasoline but since the efficiency is less than 30% with gas due to most of the energy it produces is heat. We are close....
@@ThriftyToolShed iave a couple of 16 inch saws but most of mine are the big Stihl saws, many of whom I built. I will bet those little saws will not stay with my ms 460, 440 or for the real big stuff my ms 660 and it’s 28 inch bar. Either of these saws will make your battery operated saws look like a kids toy, which is what they are. They are ok around the house but when you have to fell and buck up 25 inch hardwood they are sadly lacking.
We actually had a small engine repair shop before my Dad retired a few years back. We did a tremendous amount of saw sales and service for loggers ( I simply helped him at the start and part time when I had time) so I am not ignorant by any means on the big boys, I was talking about mine and mine alone. I have never needed a big saw for my own personal use. I only used them back then while testing the repairs for the loggers. I do remember the older McCullough 850 before the Husqvarna and Jonsered turbos were a pain to keep pulling on when you are learning to work on them, rough on the elbow. Lol. I would never compare my $200 EGO to that or my even my decent Echo 21" gas saws either. They are not even on the same spectrum. Glad I have never needed that much saw around my house.
Thank you for the superb explanations.
I'm looking to build a 5ah pack out of two of these (as optionally sold). Any clue how to wire and if the BMS/charger would work in this configuration?
I do not have these any longer since I gave them back to a friend but the best I can remember, the BMS wires are good to go and putting the cells in may all you need to do. You will have to get the pack halves separated to install but by memory everthing else is fine because the added cell is just parallel! Hope it helps
@PussMag
Great to know, it may be a resistor on board to let the charger and tool know which pack is connected then? Interesting! If I come across another one of these, I will have to look at it better....
Note that these type of packs often have configuration jumpers or different firmware based on the specific cells (2.0, 2.5, 3.0) and cell counts (1p, 2p, etc).
If I needed to replace a couple of these 4 volt cells, where could I get them and if I had to do a web search, what would I call them?
I am sure different packs manufacturing at different times are not all the same but they are 18650 li-ion cells with the rating of your pack. For example if you have a 2.0ah pack, the cells are 2000mah rating...
Heyo, thanks so much for the disassembly and info. Currently in the process of fixing up one of these 5.0Ah versions, and discovered two cells had gone completely flat (0.0V) and acted as a break in the circuit despite the spot welds being flawless. So I just took them out and swapped in similar 2500mAh 18650s I had from another battery. My question is does the on board charging circuitry balance the cells while charging or does it only apply a consistent 41/42V across the entire series for charging? That way I know for the future if for some reason the replaced cells or some other ones go bad and I need to swap in with cells that may not have the same internal resistance (i.e. go out of balance easier during discharge)
Hi,
Thanks for your comment. I do not know exactly when the balancing takes place and I am not sure of how much it can correct. I have never had to look into the balancing that close. I do try to match my replacement cells internal resistance and capacity with the pack as close as possible to help with any imbalance issues. I have always thought the pack gets balanced while charging? That may not be exact, just my initial thoughts about the BMS. Best of luck to ya on that repair!
Nice Video - thanks for posting.. So I have a Large Capacity 4.0Ah Kobalt Battery - it still seems to work in my garden tools. When I charge it also works for a while, but ultimately the charger light blinks red indicating a charging fault. I've tested the voltage of the battery after the charging fault, and it reads 37.7 volts. I haven't yet opened it up. Any guess on this one? Maybe a bad cell in there so it can't quite reach the max capacity?
Thanks for your kind comment!
Yes more than likely it's a cell or possibly more than one that has lost capacity. With cells in series one cells greatly affect the others. When pulled down low it can be lower than others causing an early shutdown for the pack and can also cause issue when charging because it will still be low when others get to the full 4.2v max. I would run the pack down to cut off point and then check if some cells are much lower in voltage than others.
@@ThriftyToolShed - BTW - would you expect these higher capacity batteries to be more prone to overheating and defects? I have 2 of the 2.0Ah ones and they seem fine. All of these were purchased a while back - circa 2015
Sometimes it does seem that way. More cells Inside, so more that can go wrong even though they can handle more current than the smaller ah packs so they are typically better for heavy loads such as blowers and mowers.
one last silly question, how in the world do you get the cells separated from the little rivets on the top and bottom of each cell.? I do not want to tear this up. The cells are hard to remove from the plastic housing!
I am not sure how your particular battery is however most I have seen are similar, I have a couple videos that I do show removing cells from the EGO 56V pack and Ryobi 18V pack you may find helpful. You have to carefully pry the tabs off and when you reattach the new cells you have to either spot weld tabs back or carefully solder the tabs back which I do show in the videos. Hope it helps!
👍
Do you jump it on the "C" terminal? I tried to charge mine through the positive and negative leads with no success. Just curious if the positve lead should be connected to the c terminal. Thanks!
No, you should not have to jump. + And - are going to cells directly. The only thing in between is the fuse! Other than that could be open cell or connection?
I have come across one of the mowers with this particular battery unit on it but it's a six amp hour and I have experience working with these style battery packs and I've had this one apart it's got 20 batteries in it 20 individuals but I'm not too impressed with the way it's laid out because what I found out so far is is it uses 10 batteries per I want to say per 20 volts and they double on each end of the pack you have a 20 volt set and another 21 set and then they run the two sets in series to get 40 volts but I don't see why this thing has so many issues it should do really well and even more powerful than I would think but my Craftsman v20 batteries at 4 amp hours seem way better than this and more dependable and I can leave them on charge and they care for themselves or take them off and they don't have many issues but I'm considering building an adapter to run my Craftsman batteries in series to use this mower because The run time on the battery I have when I first come across it was charged fully and ran good but they don't seem to want to take a good charge now so if the charger I get doesn't work right and the batteries don't work right I'm going to work on an adapter run the batteries I'm going to buy and the charger in the ground and switch it to the v20 batteries I think I'll do better they seem more dependable
It looks like Diode 080 is cracked on the charger. It might be just the camera view.
I'm having trouble with an 80V max 5ah, it charges no problem there "apparently" tested its voltage it registered 79 when I put it on my mower it lasts less than 20 minutes. Going crazy and they're expensive, when I put it in the charger no issues all green lights. Any ideas anyone?
If you do have more than one pack it is helpful to make sure the charger is charging correctly. The next step would be to open the pack up (if not still under warranty that is) and test all cells to make sure they are all balanced and that one or more have not lost capacity. When a pack gets older it is possible most of them have lost capacity, but unusual with in a few years of use. I have not worked on the 80V myself, but the 5ah@80v means most likely 40 cells packed tight in that housing. That will not be fun to work on. Unless they used 5000mah cells and did 1P 20s. Alot of packs use 2500mah cells and 2p for the 5ah rating so 20s would be 40 cells?
Outstanding!
I had a Greenworks 80 volt. After watching this video, I tested my volts and saw 63. That left me believing I had a similar issue, so I pulse jumped it for about an amp. It woke up the charging system. It then accepted normal charge again from the Greenworks charger.
Good to know, thanks for your comment!
Battery won’t eject kobalt 40 v chainsaw ! New used once! Please HELP!!
Sunny Rey I have greenworks stuff. It’s the same as Kobalt. The battery does tend to get stuck. Generally pressing the release button and giving the unit a tap or two will release the battery. Obviously use extreme caution with any tool, especially a chainsaw.
does any1 know how to take it out of the charging station
I don't understand your question. Are you asking how to slide the pack out of the charger?
@@ThriftyToolShed I have a different kobalt battery and i couldnt get it out haha i figured it out tho
the 4amp pack has a 60amp fuse
Thanks for sharing!
Great Job!!!!
Oh lookie here...we got a bubbler!! 5:53
First Kobalt 40v battery (for hedger) died after a year, so free exchange with Lowes. New one lasted about 1.5 years, now it's dead. $80 to replace. I don't like these batteries.
My Kobalt battery ended up having 2 cells that measured ZERO volts.
I am working on one right now that is the same way. It had a couple reading close to zero and some others just above 1V while a few were up around 3v and tested with pretty good capacity. So all cells are needing to be replaced. Good thing is that the pack otherwise is in great shape and maybe a good candidate to increase capacity since it was only a 2ah pack and I think I have enough cells to double up and go close to 4ah. It is not always worth the cell cost to rebuild these, but I have some from another salvaged pack and I want to try to make use of the unused cell locations and make it a 2P just to see how well it works.
That looks like over ripe TNT...
These batteries/devices are horrible... there is no logic in the devices to NOT run the battery completely dead... so.. I have to use a trickle charger connected to blades that fit the battery... for about 5 minutes... then charger works... problem stems from the charger requiring it to detect a small voltage reading before it will turn on.
Pretty close to it. Those 18650’s get very unstable if they under or overvolt. (See vape explosions)
I just bought a new 80v 6 amp max cobalt mower and the batt is prob twice the size of those but have a fan in them. They are obviously making improvements as they go.
And to think that some people will try to boost a pack without even knowing what the condition the cells are in! 😬
They never should have made that chit.