If all cells have just drained too low, then this can work as long as the cells aren't damaged. This can be rather dangerous if you don't check to make sure one of the cells hasn't dropped. If 1 cell is damaged and is at very low voltage and can't charge at all, You could overcharge the other cells, Lithium cells can catch fire overcharging them. The safe thing to do is to unscrew the bolts, and use a volt meter to check each cell to make sure they are all somewhat close to each other. If you find all of them at 3.9v for example, but one of them is 0.2v for example. Do not do this method as one of the cells has faulted or shorted. When that happens, I wait for 2 bad batteries and then sacrifice one of the cells from one and replace it in the other. Just have to be very careful doing that and requires hacking at the enclosure to do it.
Buddy… you are a blessing disguised as one smart human… been trying to find a receipt for this battery all day and then came across this video and fixed it in 15 seconds. Jump starting Kobalt batteries…. Who would of thought!!! Thanks pal!!!
I was a little hesitant at first to try your method. But, to my surprise it worked! I was able to charge the dead battery fully. Once again thanks for the solution for my dead battery.
I just want to say thank you, because my husband and I almost took the battery back, thinking that it was bad, your idea worked like a charm. Thank you so much.
Succussefly Jumped My Lawnmower Battery. I have the Kobalt 80v 5.0Ah battery for my lawn mower and it refused to charge after a year so I threw it in a drawer for another year forgetting about the warranty. Just saw this video and I used two 80v 2.5Ah batteries to jump this one 5.0Ah battery and it worked!!!! It's now taking charge. You rock!!!
WOW!! You sir, are a blessing to society. IT WORKS!! New Kobalt Ultimate Output 4ah battery. Plugged into charger, nothing but a solid green light (no blink), no charge. After 1 hour, nothing. Searched and found your video. Jumped from a Skil 20v 2ah battery for 30, then 40 seconds. Plugged Kobalt back into it’s charger….blinking green light and taking a charge!! THANK YOU, THANK YOU for posting this video.
Great tip! I thought my Kobalt 40v battery/charger was dead but your suggestion allowed me to get the battery recognized by the charger. Let it charge overnight and the next day it was like new.
Thank you!! This worked. I had a Greenworks 80v battery that I didn’t use for a year. So then I did your method with another 80v Kobalt battery. I left it for like 5 minutes and it’s charging now!!
Wow! I just bought a charger with 2 battery bundle. One battery charged, and the other wouldn't. I took it back to Lowe's and got a replacement. But the replacement also made the charger flash red. I did what you show here, and it worked like a charm.
Thanks a ton, this trick even worked using 56v to fix a dead 80v. Since I metered the 80v dropped to 37V😂. The battery light didn't turn on, but after a min or two the charger is now charging it.
It works! I did it for a few seconds and it wasn’t enough. Then did it again for 10 seconds or so and it had a little flash fire. I tht ‘o well it was dead anyways’ To my surprise, it had some juice. Kobalt brand
Genius, it worked for my 80v Kobalt leaf blower battery. Used it outside in the cold and battery died will using. Could not recharge cause charger kept flashing red even after letting it sit at room temperature for days. This method saved my battery, though I had to let the 2 batteries connected for a good 30 minutes ( probably because of the size of the battery. Thanks again!
I just did this and it worked. Thank you so much. I put the battery in the charger and at first the light didn't come on. Then all of a sudden the charging light started flashing green. Amazing!
Holy Smokes! Worked like a charm!!! In my case, I could not get any of the 4 lights to come up...100% dead as a door nail....I used actual wire (just what I had on hand) and left them hooked up for about 30 seconds...and then it worked! STELLAR WORK HOMIE
You, Sir, are the man! I just bought the double 4ah battery with a free tool, and after an hour of charging, the first battery I charged did not work. I was mad because now I had to make another trip back to Lowes. Then I figured I'd look for solutions on RU-vid and saw your video. I just thought I'd give it a try before going to Lowes, and lo and behold; IT'S ALIVE! LOL. Thanks for the tip!
I can’t thank you enough! I threw the battery in the trash, but now I can go ahead and get that bad boy back out and try this! I was so confused because I’ve had it less than a year and only used it a few times in a hedge trimmer lol. You are a life saver-er battery saver?! 😂❤
I had the same problem on a kobalt 24v battery that came with reciprocating saw I bought off marketplace. Jumped it like u did, it worked. Now has and maintains full charge.
While I don't currently have some spare wire to do this to a battery I know works cause I used it a few days ago, but forgot to take it off a air compressor, I appreciate this tip and will use it at my earliest opportunity, thank you in advance!
Thank you so much!!!! It worked perfectly!!! Only took. Minute or so I used old speaker plugs cut off the ends stripped the wire and like magic I’m back in business!!!!!
YOU'RE THE MAN!!!!! I purchased a used battery at an auction for cheap. When I got it home it just flashed red in the charger. I did your trick by jumping the batteries and now it works. I was almost going to throw it away, but now it works!! If I know where you are I would buy you a beer!! Thanks!! P.S. What do you do if you don't have a second battery? LOL
WOOHOO!!! You saved the day! Or, well, you saved the BATTERY!!! LOL! We were about to throw the battery out and decided to search RU-vid and luckily we found your video. This worked like a champ and in just a couple minutes we have the battery now charging properly. Thank you!!! Subscribing to your channel to see what else you can help with!! :-D
I tried that with my Milwaukee 12 amp battery and it didn’t really work, I was able to get a full charge but the battery only last 10 minutes 🤷🏼♂️. Have a great one Lucas 🙋🏼♂️🙂👍🏻
I have a bad kobalt charger, so I will gut it and add a mechanical timer and a wall wart power supply. Just install the battery and turn on the timer to bring it up a it. Since it is a slow low voltage charge one can leave in on longer like 15 minutes. I"ll just need to decide with a dc amp meter what size fuse I'll use. Use a slow blow at about 10% higher than the initial spike.
Every RU-vidr gives the exact same solution which is just great if you have TWO batteries. What are you supposed to do if you only have ONE? Or what if you have a second battery but it's less voltage than the one you're trying to get up to charge so your charger will recognize it?
Ok so I drive a semi. I use the 40v blower on the daily. Came to watch the video for help. Only problem is I don't have a second battery or wire. What I did to get mine back to running was put battery back in cradle and turn the inverter directly off and back on and it jolted it back to life.
I have a 24V 4AH battery that’s rarely been used. I got it last year or two years ago at most, it came with the blower. It works when it wants to, but often all four lights on the battery flash at the same time for quite awhile. When I charge it the charger flashes green like it’s charging for a couple seconds and then goes solid green like it’s fully charged. However when you press the button to check the battery level it again flashes all four lights red at the same time and only works when it wants to.
Thanks! Got a battery with a tool deal, and then saw it was a pretty old manufacturing date. Then it started having trouble in the cold to recharge, then it just wouldn't. A few seconds jump and the charger was OK to charge it. Hopefully I can squeeze some more value out of this battery before it totally dies. Maybe I'll label these and stop using them when there's 1 bar remaining.
I've got 2 batteries that wont take a charge and the charger shows green as if they are charged. Can't figure out how to charge them besides jumping them to another battery. any advice for this problem. They are 4ah ultimate output batteries with somewhere over 22v in them. if i jump them to a good battery they will indicate 1 led of charge and run tools briefly. no matter what i do they show green on the charger.
I have way more of a sense of adventure than common sense, so I tried this method and it WORKED!! Yeah!! I must admit that at first I accidentally reversed the poles and I don’t think I’ll be needing any coffee for the next few days.😂
Thanks for the info i have a 80 volt max kobalt battery that will not charge so i am going to try this tomorrow and hope it works for me because I done bought to new charges thinking that was my problem and it wasn't so i sure do hope this works for me
Thanks for the video, I have a new battery , that I have only charged once , it got stuck on on in my tool box in my Jeep and killed the battery ? My question is I only have one kobalt battery if I try this cam I do it from a lower volt battery from my craftsman batteries ?
Mine take charge for a bit, light is green showing is fully charge on charger, but only one light on battery shows that needs more charge. So mine does take charge but it doesn't charge all the way. Will this method help?
My Kobalt 24v battery does charge and is green. But the problem is when I plug that Kobalt battery into the Kobalt 24v tools, the tools do not power up. Is there any way to fix it? Thanks.
In my case it does flash as if is fully charged just solid green light, but when u click on the battery it does display as only 1 bar left , would doing this fix that issue ?
Wish this worked for me. Tire Inflator drainied mine dead. This will get it to all 4 green lights flashing, but won't ever start to where it will take a charge.
No go for me, fried the good battery I used for the jump. It won't even flash now. Bad one will still flash. 24v. kobalt black. Now down 2. These were my newest batteries[ 2020] . I have a half dozen regular blue 2.0 & 4.0 that are 6 years old & work fine... Still love my kobalt tools though .
it doesn't work for me, I've seen the dead battery flashing when it is connected to the good one. I left it connected for about 1 hour, and put it on the charger, it still does not register
Thank you for your video. Good one. I dodn't have another battery to charge the discharged one that turn the light red, despite that I tried pluigging it carefully, so what I did is just took the battery and by frictionk: rubbed it against my pijamas and plugged it again and started charging with the green intermitent green light: you gave me that idea of charging a dead battery even a little bit, I guess the static charge could have done it, I guess, thank youi.
I did this for my 40V battery for my Mower. All bars shows on the gauge when hooked up to the good battery... but soon as I unhook it will not charge (charging light does not come on) and the light in the battery doesnt gauge come on. Any thoughts?
Will this work if my charger shows a solid green light when the battery with 1 bar showing is plugged in but the charger won’t kick in and charge the battery, the charger is good as it will charge other batteries.
The problem with mine is, is that my battery charger will flash green as if its charginging one of my batteries, but it will flash maybe 4 times then fully illuminate as if the baterry is already charged. The battery never has mor than one green bar on it.
I have 2 Atlas batteries that say the are full but won't work in my mower or other tools, I got two new ones and the tools work so it's not the tool, would this be something similar or different repair ?
My comment is not on charging but FYI. If battery starts flashing and drill or impact won't work unless re- inserting battery then I found letting switch snap back to off stops the problem.