The items used in this repair Venlab Digital Multimeter UK amzn.to/3KDi805 USA amzn.to/3MlEep8 DC power supplies UK link amzn.to/3LMSO93 USA link amzn.to/42ya87A
30v 0-10A, Is my DC power supply I just got yesterday dead? The (V) I set it to 1730V, it is steady on 1756-1757v. The (A) and the (W) is reading zero not running.
This method worked for my battery that showed 1 bar only but would never charge past it on the dewalt charger. I slow charged it for 3-4 hours and it came back to like. I spent $30 on a dc battery charger from amazon to save a $180 dewault battery. Well worth it. Thanks for making this video!
I got some 6ah and 9ah flexvolt battery with 1 bar and 2 bars. The 2 bars battery, it will charge but will not charge up to 3 bars. How do you know what volt(V) # and Amp(A)# to set on the DC power supply? I don't know so I just put the same # like you did here. I charge the battery with no bars, after 5hr plus, it is showing one bar. I shut it off and try to charge it in the battery charger but it is still not charging. I hook it back on the dc power supply to charge now why is my (A)amp and my (W)watt display is reading zero?
What’s concerning to me as I’ve been buying quite a few of these Flex Volt batteries is that this one in the video is only 5 years old, it doesn’t look abused and yet it’s essentially dead. That’s a $200+ battery, DeWalt needs to step it up. I have 20V batteries that are 10 years old or better that are all still fine, being used daily.
I am having a similar issue but when I try using the desktop dc charger I set the voltage as younahve shown and set the amps to approx 0.5 but after a while it drops to zero on the amps any ideas ?
Have a 9ah that reads 17v between b terminals. Almost never used, charged less than 10 times. Was able to run a Dewalt chainsaw with what was left in it but will not take a charge now. Any ideas? Charger is working on another 9ah. Will charging with a desktop power supply balance the cells if thats the issue?
Have the same problem with Milwaukee 8.0ah battery which charge only 3 bars without completing the 4th and have a 12 ah with no charge as well, opened it and checked the cells 3 of them was 3.8 and others are 4, I need to find a way to balance them now, which I am gonna try, this coming weekend 🙂
I'll have to try that if I had a heat gun. My 9AH won't charge. I watched this video that explains what the main problem is: th-cam.com/video/ZJHKoo2shBA/w-d-xo.htmlsi=scqrbh1N1hQQ_HsU
Thanks for this videos, i got the same 9ah flexvolt. But my problem is that it doesn't charge over one bar. Do you think jumpstart would work or some cells my be dead? Thanks for your help❤
Good question and I managed to get one going that had the very same issue I used a USB adapter on a ring light to drain the battery down low then brought it up using the power supply as shown in the video to around 17v it then took a charge
Careful with that, I just diagnosed such a battery for someone and one cell was at 5.3v and another was 0.3v. That 5.3v cell is a pending home insurance claim. A cell under 2v can't be recovered, it has to be replaced.
The cells have a little failsafe on them that breaks the internal connection rendering the cell useless if it gets over heated of overloaded. The failsafe is more likely to deactivate the cell. If the cell doesn't deactivate you can experience something called thermal runaway where a cell keep heating up until it explodes. This is very rare and I have never experienced it yet but it is highly dangerous.
Hi there I have a problem with my DeWalt 6ah as soon as I put it in the charger the light comes on and then off straight away. Any idea what could it be ? There's no breaks in the nickel contact bars.
Any 18v/20v dewalt charger charges a flexvolt it will charge quicker on the dcb118 than the one shown here. Flexvolt don't charge at 54v/60v they charge at 18v/20v.
Had a flexvolt saw burn out on me and the 54v battery that was in the saw only works in 18v tools now is there a way of fixing that? Maybe its stuck in 18v? Any ideas? (Tried another 54v battery in the saw and that too only works in 18v tools)
You suggest the second battery only works at 18v too. Did it work on 54V before? As if trying it in the burnt saw broke the second battery? have you tried the shorting of C1 to C3 and measuring output voltage?
@@ianhelsbyservices yeah both 54v flexvolt batteries where working before on 54v now after been in the burnt out saw both only work on 18v tools. I'll try short the c1 toc3 when I get home Thanks for replying
I have an issue with a 9ah flex volt, goes on charge, but stops charging after 5 mins, only one led bar lit on indicator, but charger says its full. Got 16.5vdc across B+/- terminals, can this be saved?
@doctorlefthandthread everything is intact, no burnt or broken connections. I used a jumper across C connections and pushed plungers, got 49.7v on the 54v side. Digging a little further I think I have a dead cell. One is reading 0v, with all others giving 3.4 to 4.0v
Thank you for commenting yes you are correct the right thing to do is test it on a 54v tool. So why didn't I? The simple answer is I did not have a 54v tool available that day but it did work on 54v. I did get it tested later.
The jump Start is frowned upon by some due to the sometimes volatile nature if lithium ion however you can use a dc power supply to bring one of these batteries up slowly
I thought that being 6 volts across the pack would mean it's dead as a doornail. I got a 12ah here with water damage and it's reading 0 on most cells. I doubt this would work for me
Probably not. sometimes if there is some kind of voltage you have a chance to bring it back. conventional wisdom would dictate that if they are below 3v volts I am not conventional or wise so sometimes it works for me
@@doctorlefthandthread got a 6ah, its a 2022 battery in great condition. Wont charge but voltage across the pack reads 14 something volts, would ya say its fixable?
@@doctorlefthandthread no broken connections, looks like someone's resoldered the board on but the battery works in 18v and 60v. It just has a solid light on the charger and the cells are all 3.3v after i jumped them but still no luck. Might see about replacing the board
I've been given two 9AHr batteries to diagnose. Charge and work fine on 18V but no 54V tool to test. Tried the jumper between C1 and C3 but no change. Output is 20v then when you press the side buttons it graduslly drops to 0v as if output disconnected and capacitor discharging. Any ideas?
@@doctorlefthandthreadi must apologise. Turns out I hadn't pushed the side plungers in far enough. Half way in drops the voltage to 0v over time. All the way in so you can't see the black plunger any more gives just over 60v. Batteries all check out, must've been the dirty contacts!
The items used in this repair
Venlab Digital Multimeter
UK amzn.to/3KDi805
USA amzn.to/3MlEep8
DC power supplies
UK link amzn.to/3LMSO93
USA link amzn.to/42ya87A
What unit did you buy? 30v 5ah or higher?
30v 0-10A, Is my DC power supply I just got yesterday dead? The (V) I set it to 1730V, it is steady on 1756-1757v. The (A) and the (W) is reading zero not running.
This method worked for my battery that showed 1 bar only but would never charge past it on the dewalt charger. I slow charged it for 3-4 hours and it came back to like. I spent $30 on a dc battery charger from amazon to save a $180 dewault battery. Well worth it. Thanks for making this video!
Great to hear
I got some 6ah and 9ah flexvolt battery with 1 bar and 2 bars. The 2 bars battery, it will charge but will not charge up to 3 bars. How do you know what volt(V) # and Amp(A)# to set on the DC power supply? I don't know so I just put the same # like you did here. I charge the battery with no bars, after 5hr plus, it is showing one bar. I shut it off and try to charge it in the battery charger but it is still not charging. I hook it back on the dc power supply to charge now why is my (A)amp and my (W)watt display is reading zero?
What’s concerning to me as I’ve been buying quite a few of these Flex Volt batteries is that this one in the video is only 5 years old, it doesn’t look abused and yet it’s essentially dead. That’s a $200+ battery, DeWalt needs to step it up. I have 20V batteries that are 10 years old or better that are all still fine, being used daily.
I agree the failure rate of the flexvolt batteries is too high
I am having a similar issue but when I try using the desktop dc charger I set the voltage as younahve shown and set the amps to approx 0.5 but after a while it drops to zero on the amps any ideas ?
Had this same thing happen on that same 9ah pack. I charged it using a hobby charger at various cell count settings..
What volt and amp should i charge each sell at individually pal
What charger are you using?
30v 5amp
@deanthompson6664 I would set the amps low probably 2amp and the voltage at 4v
Have a 9ah that reads 17v between b terminals. Almost never used, charged less than 10 times. Was able to run a Dewalt chainsaw with what was left in it but will not take a charge now. Any ideas? Charger is working on another 9ah. Will charging with a desktop power supply balance the cells if thats the issue?
Sometimes running it down to a very low voltage then bring it up with a desktop power supply can work. It has for me but it doesn't always work.
Have the same problem with Milwaukee 8.0ah battery which charge only 3 bars without completing the 4th and have a 12 ah with no charge as well, opened it and checked the cells 3 of them was 3.8 and others are 4, I need to find a way to balance them now, which I am gonna try, this coming weekend 🙂
Makes sense they are out of balance
Had a 6 Amp Flexvolt refuse to charge today. So I stuck it on a heat gun and ran it until the heat gun stopped. Then the battery charged! Happy days!
Works sometimes
I'll have to try that if I had a heat gun. My 9AH won't charge. I watched this video that explains what the main problem is: th-cam.com/video/ZJHKoo2shBA/w-d-xo.htmlsi=scqrbh1N1hQQ_HsU
Thanks for this videos, i got the same 9ah flexvolt. But my problem is that it doesn't charge over one bar. Do you think jumpstart would work or some cells my be dead?
Thanks for your help❤
Good question and I managed to get one going that had the very same issue I used a USB adapter on a ring light to drain the battery down low then brought it up using the power supply as shown in the video to around 17v it then took a charge
Careful with that, I just diagnosed such a battery for someone and one cell was at 5.3v and another was 0.3v. That 5.3v cell is a pending home insurance claim. A cell under 2v can't be recovered, it has to be replaced.
5.3v wow yeah that's high
I've heard jumping these batteries can turn them.into a fire hazard. Is that true? If you have a dead cell it over charges the other cells
The cells have a little failsafe on them that breaks the internal connection rendering the cell useless if it gets over heated of overloaded. The failsafe is more likely to deactivate the cell. If the cell doesn't deactivate you can experience something called thermal runaway where a cell keep heating up until it explodes. This is very rare and I have never experienced it yet but it is highly dangerous.
Hi there
I have a problem with my DeWalt 6ah as soon as I put it in the charger the light comes on and then off straight away. Any idea what could it be ? There's no breaks in the nickel contact bars.
Could be dead cells or something else popped on the board
@@doctorlefthandthread my 9ah had some visible bits of coating missing from the board and it only charges one bar
a great Vid, I thought that you needed a dcb118 charger to charge 9ah batteries?
Any 18v/20v dewalt charger charges a flexvolt it will charge quicker on the dcb118 than the one shown here. Flexvolt don't charge at 54v/60v they charge at 18v/20v.
@@doctorlefthandthread I thought that But me asking Will help others in the future whit the same question
It Sure will thanks for all your comments and questions.
Had a flexvolt saw burn out on me and the 54v battery that was in the saw only works in 18v tools now is there a way of fixing that? Maybe its stuck in 18v? Any ideas?
(Tried another 54v battery in the saw and that too only works in 18v tools)
You suggest the second battery only works at 18v too. Did it work on 54V before? As if trying it in the burnt saw broke the second battery?
have you tried the shorting of C1 to C3 and measuring output voltage?
@@ianhelsbyservices yeah both 54v flexvolt batteries where working before on 54v now after been in the burnt out saw both only work on 18v tools.
I'll try short the c1 toc3 when I get home
Thanks for replying
Try this too
th-cam.com/video/2tTX7DJywig/w-d-xo.html
I have an issue with a 9ah flex volt, goes on charge, but stops charging after 5 mins, only one led bar lit on indicator, but charger says its full. Got 16.5vdc across B+/- terminals, can this be saved?
Possibly try this first
th-cam.com/video/IUlHVVt-ptg/w-d-xo.html
@doctorlefthandthread everything is intact, no burnt or broken connections. I used a jumper across C connections and pushed plungers, got 49.7v on the 54v side. Digging a little further I think I have a dead cell. One is reading 0v, with all others giving 3.4 to 4.0v
@@grantmacdonald3126 hard to change a cell in the flexvolt
Why did you test it on an 18 volt tool and not a 54 volt tool?????
Thank you for commenting yes you are correct the right thing to do is test it on a 54v tool. So why didn't I?
The simple answer is I did not have a 54v tool available that day but it did work on 54v. I did get it tested later.
could you design and produce a Jump-start charger product for sale.
The jump Start is frowned upon by some due to the sometimes volatile nature if lithium ion however you can use a dc power supply to bring one of these batteries up slowly
I thought that being 6 volts across the pack would mean it's dead as a doornail. I got a 12ah here with water damage and it's reading 0 on most cells. I doubt this would work for me
Probably not. sometimes if there is some kind of voltage you have a chance to bring it back. conventional wisdom would dictate that if they are below 3v volts I am not conventional or wise so sometimes it works for me
@@doctorlefthandthread got a 6ah, its a 2022 battery in great condition. Wont charge but voltage across the pack reads 14 something volts, would ya say its fixable?
@@konstantine381 it could be check for broken connections th-cam.com/video/dDP1SHhLgL4/w-d-xo.html
@@doctorlefthandthread no broken connections, looks like someone's resoldered the board on but the battery works in 18v and 60v. It just has a solid light on the charger and the cells are all 3.3v after i jumped them but still no luck. Might see about replacing the board
@@konstantine381 what voltage do you have at the 60v range?
I've been given two 9AHr batteries to diagnose. Charge and work fine on 18V but no 54V tool to test. Tried the jumper between C1 and C3 but no change. Output is 20v then when you press the side buttons it graduslly drops to 0v as if output disconnected and capacitor discharging. Any ideas?
There may be a burnt out connection I would guess this might help th-cam.com/video/2tTX7DJywig/w-d-xo.html
@@doctorlefthandthreadi must apologise. Turns out I hadn't pushed the side plungers in far enough. Half way in drops the voltage to 0v over time. All the way in so you can't see the black plunger any more gives just over 60v.
Batteries all check out, must've been the dirty contacts!
Cheers 🎉
Thats how it should be done nice one. BTW the 6Ah flex uses 18650s
It does thanks for your advice regarding that I am getting there
So did the older 9ah apparently.The ones with the silver tabs on top had the upgraded cells.Ive got both.(vs 21700 cells)
@@garthqueen The older 9Ah (mid 2018 and prior) used Sanyo 20700 cells, not 18650s.
Dewalt will replace defective batteries
In USA yes not UK or Ireland sadly one year warranty except powerstack where you get 3 years if registered