Back from the DEAD! Lithium Batteries!

www.realtoolrev...
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** USE CAUTION!!! **
Lithium Batteries can & will catch on fire or explode if overheated! Do not attempt to revive completely drained, damaged, or unknown batteries --- only attempt to revive them IF they are still holding a significant charge! (as shown in the video)
MOST "dead" batteries are beyond repair --- meaning you never want to disassemble them or replace parts. If this trick does not work, return the dead pack to the manufacturer or recycling center!! DO NOT OPEN THE PACK UP!
Do NOT attempt this indoors!
Do NOT attempt this near flammable items!
ONLY attempt this outside in a driveway or parking lot in case of fire!
If you are not comfortable, do not attempt ---- contact the manufacturer for a replacement and/or bring the battery to your local recycling center for disposal.

[@jameshalleron7484]

Thankyou for explaining how to charge a dead battery without alot of unnecessary chatter. Your warnings are warranted and much appreciated.

[@robsdeviceunknown]

So I bought a lot of about 11 batteries, and some other misc milwaukee tools. for like $350. I think the seller was trying to pull a fast one on me. All batteries were so low that one light wouldn't light up. After watching this I charged them ALL. Jokes on him now. 1x M12 with that 1H saw, 2 M18 Circular saws, 11x2AH Batteries, 1x60V DeWalt and 1x6AH DeWalt oh and a DeWalt abrasive cutoff saw(needed 9 dollar brushes, why on a new saw I dunno) all of it was brand new. All works now. Boy I owe you guys one for sure.

[@RealToolReviews]

Haha nice 👍

[@LibertarianUSMarine]

all batteries are at minimum load when you buy them brand new sir.

[@johnathansmith3819]

@Rob Lambert - find out where Mr. Marketing for Milwaukee lives, and personally deliver a letter...

[@ocdtechtalk]

Excellent video I've watched several being an electrical engineer you're the only person who covered gauge of wire. The only other thing I would recommend is to put in a inline fuse. Thanks for sharing.

[@toonwintersturm1045]

What amperage fuse would be appropriate?

[@ocdtechtalk]

@@toonwintersturm1045 the current should be very low. I would start with a 1A fuse. Or course you can measure it with an amp meter.

[@patcotsman866]

This is a spot on video. I have done a similar thing by using a variable power supply and adjusting it's output to limit current to less than one amp. You didn't need background music or gloves----congrats!

[@mark86326]

Mark Munro. The DC motor is also a DC generator turn your drill with another drill with the switch held down. That puppy should take a charge.

[@kennethdalebristow3192]

Thank you for being so thorough on your procedure and safety.

[@deanlevett888]

Excellent advice had a nearly new battery, that wouldn't charge from the charger. Tried your jump start. Gave it 5mins, and now it is charging from the charger. Thank you for your video, saved me £50. 👍👍👍

[@jasonh4534]

Its called balance charging... A good lithium charger will read the voltages of the individual cells, even better chargers will charge each cell independently to ensure they all are at the same level. If the voltage of the entire pack is high enough to run the tool, but one of the individual cells is faulty or somehow discharged to a lower than safe voltage... Then the charger will not allow the battery to charge, due to the dangers you mentioned. Any cell that drops below the safe voltage will have its capacity significantly diminished as well. As time goes on, subsequent recharges on these bad cells can increase the danger of fire. If that is not the case, and the tool still runs even after the battery is below safe voltage levels... Then the battery pack and/or tool does not have a safety circuit, and that is bad. The specific chemistry type of the cells used to make the battery will determine their tolerance of abuse... With Lithium Iron (LiFe) being the safest... As they tolerate the use conditions and abuse conditions of power tool use the best... But with the push to higher voltage batteries, the use of LiFe type cells is decreasing, as they have a lower 3.2v nominal working voltage per cell, and higher weight per cell than other formulations.

[@jmackinjersey1]

The thing is, this is great for lower end/priced tools/batteries, like the Porter Cable he used, Ryobi and older Ridgid etc. But as you said, higher end battery chargers will have a better communication system.

[@Pro1er]

Another, (potentially safer), way to charge a battery is to get a power supply off of eBay. You can set the correct voltage for your battery and supply a low current trickle charge to bring the battery up to a higher voltage. This avoids the chance of pumping a large current from the host battery into the low battery which could be hazardous. I would recommend using 0.5A or less so as not to damage the cells. You can often bring a battery up to a level that the OEM charger will accept within a matter of minutes. A 30VC 3A power supply can be had for less than $40 shipped and can useful for other projects as well.

[@RealToolReviews]

Thanks for the tip!

[@machotires72]

thank you

[@HifiCentret]

I sure do agree you should definitely NOT just wire them together like they where car batteries. That's potential very dangerous for the low voltage pack to receive such a huge amount of current in a low state. However no need to buy a power supply you could just put in a suitable resistor or constant current diode or mosfet you wired up to act as a suitable constant current diode. Preferably at even lower current. Just let them sit an have voltage rise very slowly. When enough put it on the regular charger. I don't however understand why the original charger refuses to charge them at 13,9 v. It's 2,78v / cell and that is not that low. I believe the safe limit for LiIon is in the ballpark of 2.2 v/cell give or take a little. That low current should be limited to as low as 50 mA making using constant current diodes or a LM117 very suitable for the job.

[@EJP286CRSKW]

That would need to be a power supply _with current limiting._

[@cbprescott77]

You might also put a fuse in series with the power side of the battery to limit damage if the old battery is shorted.

[@mrstanskaggs1]

The cells on this unit are Samsung INR18650 cells (5 of them). They are 3.6V cells which comes out at 18 volts. The packs are labeled as 20 volts in that 20 volts is the charging voltage for these cells (4.2V charging X5=20V). If the cells get imbalanced in terms of standing voltage, it reports as a bad battery. The multiple connectors on the battery pack reach in between the cells. Looking at the connectors on the battery, you should see roughly 20V from right side (+) related to each of the other three connectors... but no reading from the left connector to either of the middle connectors in any combination. Opening the battery shell, you can specifically measure across any individual battery. Each battery unloaded should show 4.1 volts charged. The key is not to look for 4.1 volts though, but a difference between each cell individually. The circuit board has a comparator circuit which makes sure each cell is within 0.1V difference (charger is a balancing charger in other words). These cells are the same as people put in those nasty vape machines, so you should not be too scared of them.. I find it best to charge each cell alone and watching the resulting voltage on each cell until they level out to the point that the comparator allows them to charge on the charger once again. ... sounds a little complicated, but it is simple actually.. The packs are not glued together thankfully, and the sides of the batteries are easy to access once the case is opened...

[@exgenica]

KEEP DRY SAND NEARBY FOR LITHIUM BATTERY FIRE CONTROL Do NOT use water to try to put out any lithium battery fire that occurs. That includes some fire extinguishers. Water can in fact make lithium-based fires much worse and/or cause explosive projection of flammable material to nearby objects/people/pets. Keep a fairly large amount of sand or dirt on hand to smother any lithium battery that starts to smoke or is on fire, or that you hear start to "crackle", or if you see it start to discolor/blacken. Also, I would keep a separate appropriate fire extinguishing method on hand to help control/put out any secondary fire(s) that are not adjacent to the battery itself (e.g. if fire spreads to grass, trash, clothing, or other objects). Because lithium battery fires can be VERY fast, explosive, and quickly spread and "jump" over small areas of cleared ground into nearby brush, furniture, etc...I'd personally keep handy an extinguisher rated at a MINIMUM of "10A". I'd also make sure I wasn't testing things near sources of flammable liquids, other electrical equipment, and people or animals and over-hanging tree and bush leaves and branches. I realize this is boring stuff, but sometimes we just forget to think of these things when in "debug" mode.

[@jhm2112]

Appreciate the video! I did this with a porter cable battery that only registered 4 volts and wouldn’t charge. Now I’m able to use the impact driver the battery was connected to. Thanks!

[@alnavajo6733]

Love it! I did the same setup to charge my 10 year old stream light battery and it brought it back to life. I started off with 0.159 millivolts when I last checked it it was at 2.9 volts. I had to my new battery to trick the charger into sensing the battery voltage from my new battery to charge my old battery once it started sensing 2 volts I started charging my old battery directly with the charger.

[@jackkohanim590]

Great info. I have two DeWALT 40v batteries. One of them stopped charging last year and I didn't want to spend the $192 to replace it. For some reason I held on to it thinking I would be able to take it apart and replace the guts of it. Well, now with this video, I followed your instructions and wired it up initially for 5 seconds and it pushed it up from 36.9 to 38.1 and now it's charging. Thanks for the detailed explanation of what happened and why it wasn't working. Hope all is good with you.

[@cactassdupree7285]

I like the jumpers you built. And the explanation is spot on.

[@juanr859]

Thanks for sharing your expertise. I would like to highlight your “beyond excellent” verbal skills.

[@mcg6762]

With a large voltage difference the current is going to be very high and can damage both batteries. A way better option is to use a current limited supply to bring the voltage up of the low battery. And only do this if the voltage of the low battery is close to the threshold. If the voltage is very low probably one or more of the cells have permanent damage and can fail in dangerous ways.

[@wyattoneable]

I love that you explained the marketing voltage. Sneaky. Great video and tips.

[@RealToolReviews]

Haha.....yeah, marketing depts everywhere hire some creative people ;)

[@JoseMartinez-ou4ej]

Gracias Maestro. You are a great Teacher! The way you explain is cristal clear. Thank you!

[@OcalaKitty]

Yes! Will do. You do a great job of covering bases. Home run for your comprehensive method of presenting info with cautions.

[@freedomseeker01]

Great content. Also great delivery. You've got the right voice for it, tempo is good, diction is great. Thanks for doing this.

[@jJimmyBGreat]

I'm glad you could get back to drilling random holes in scrap 2x4 in a machine vise. Thanks for the info. I'm gonna go try this.

[@GermanToolReviews]

Thanks for the tip. I have also seen this when you leave a battery on the shelf for year and then go to charge it and it is below the cutoff voltage. One warning I would have when you connected the two batteries together is that a power resistor in series would probably be a good idea to limit the current. I'm guessing that most battery packs already have something like this in the circuitry but some cheap ones may not.

[@angleturner]

Seriously ?

[@garydiamond6078]

How much and what watts, I can see you point, and would put a meter across it, and when it goes to zero, it's time to charge the battery, unless of course your using a much higher source of voltage then the battery your trying to save is

[@robertworkman1249]

😊

[@Thinker2-truth]

Lithium Batteries employ a BMS to prevent the batteries from catching fire. It is the BMS not batteries that most often fails. Either turning the BMS OFF (no power) or blowing the BMS circuit (damaged).

[@0zyris]

So are the + and - terminals reversed on those two batteries? If you were using two matching batteries you would need to cross the leads over surely?

[@yellow_panther]

It looks to me that he connected positive to negative between the two batteries. When he tested the voltage with the meter, the positive was on the same side on both units

[@ramesh4433]

Haha.... Try it, u are going to blown it up 😂...

[@loktom4068]

It really works. I got the same information from another video . My problem was a set of new unused M18 Milwaukee batteries were sitted in storage too long. It won't charge even left 18 hours in the charger. All were less than 3.5 volts. The warranty were over. I boosted them with an old nicad battery with only 14.5 V for 15 min. It brought the M18 Milwaukee batteries back from 3.2 volts to 14 volts. The M18 Milwaukee charger immediately recognized it and charges both from dead to full. I fully tested them for usage. The results were excellent. Almost throw them all away.

[@tomrainwater3203]

That shit don't wirk

[@TheZigwah]

Wow you are truly an Exceptional Educator Great explanation of and clear warnings Thorough without excess Ive done this technique before, I just was so happy to see a KZbinr give the complete correct information

[@RealToolReviews]

Thanks!

[@bostonxpat]

Definitely genius!! But that said begs the question(s) how much use now on a single charge can you run that "reconditioned" battery before it runs too low again? Also, what is the voltage threshold where you just dispose of it rather than try to revitalize it?

[@jeffhilander]

What a good teacher.

[@NoComment-oc6di]

this guy is a boss !!! so clear and concise in his explanation

[@Dirtyharry70585]

lithium with burn like a road flare and will not stop until consumed. Also it will create deadly fumes, so ALWAYS do this outside.

[@phbrinsden]

Very good advice. If you are going to take a chance doing this then outside is absolutely right.

[@mickdunne007007]

Excellent advice had a nearly new battery, that wouldn't charge from the charger. Thank you for your video, saved me e48.00

[@RealToolReviews]

Glad to help!

[@mySelf-yx4hw]

Did the same thing myself bought an 18 volt Hitachi drill with 2 dead batteries got the batteries going again using the same method and it's still going strong more than 2 years later good advice about doing this outdoors, friend of mine was swapping old Nicad batteries and fitting Lion we did warn him about the charging issues, he later sold it on and had to pay the money back when the batteries caught fire and almost burned down the guys kitchen

[@markduran2942]

Hello from Austria, THANKS! this worked for me. Reincarnated my jigsaw battery in 10 min.

[@nkuutujeremiahbrianchoosen9691]

Thank I will try out and see if it helps

[@stephenwetmore3747]

Great voice and great communicator.

[@wcurtin1962]

Keep in mind if you put two of the same batteries nose to nose the positive terminals will be on the reverse side so the wires you put on will need to be crossed instead of being straight.

[@timsemerdjian2344]

Awsome mate , I'll follow your suggestion and see how it goes . A very comprehensive explanation, well done .

[@1414141x]

Great video and helps people find out if they have batteries that can be persuaded to re-charge. Most people just give up and buy a new unit. Particularly liked your comment about the 20v actually being an 18v unit. I have a 20v paint sprayer so I know know I can use my 18v batteries of my other power tools to use the procedure you showed. Many thanks.

[@ajmedeiros77]

20 volt MAX, all marketing bs like many of them do

[@usewisdom]

Thank you. Worked perfectly with video camera lithium ion batteries.👊🏾

[@robertjahrling1877]

Is this guy joking or what I really don't want things blowing up on menot that I care about the old dead batteries but I do care about my toes my fingers my eyeballs LOL

[@vistron888]

On all my Hitachi 18v li-ion power tools they just stop working completely when the battery needs charging. Got 6 batteries and not a single one has had a fault to date. Think it is also advisable to store your batteries indoors rather than left overnight in a shed or van in extreme temperatures.

[@len4709]

I bring all my Bosch batteries indoors every day, mostly just in cold weather. Had some for 10 years and still work! I would definitely agree with you

[@1bottlefed]

One thing to keep in mind is that a compromised cell will not always fail during charging. It may instead charge fine but fail when you apply load to it during use in your house.....just food for thought.

[@9UaYXxB]

This comment needs flashing strobe lights around it !

[@ericyuan2305]

I just try the way you showed us it works just as you said. Thanks for sharing this video to people. I subscribed your channel and will follow.

[@MrBecker666]

you can get a variable DC supply for $15 and do the same for different batteries/voltages...I've revived a bunch of cellphone batteries(even fancy iphones) the same way

[@djg585]

I appreciate the conciseness.

[@handymanandymanllc4739]

Are these both the same brand of battery? Because if so, you connected the polarity reverse.

[@ierwin88]

I saw the same thing!!! The two batteries I have are for the same tool so it would be connected + to - as shown in the video. I should know but wouldn't sparks fly if they were mis-connected? I assume he would have known what he was doing?

[@ericduplantier9691]

Really cool hack. I was always told you can't do anything for a lithium battery. I do know you can jump the old nicads. Thanks for the info

[@ccdogpark]

You did a nice job with this video. The biggest problem with these lithium batteries is that if you forget and leave them charging indefinitely, that will kill the battery pretty quickly. Is this a way to solve that problem ? Do you know the difference between a Type 2 and a Type 3 Black & Decker Lithium powered tool ?

[@ellobo4542]

Thanks , I was looking for something else . This will help me with a few dead batteries I have. Can't wait to try it out .lol

[@bradleylalonde3523]

Great video really appreciate it it actually does work had a two amp Milwaukee battery with two cells at 1.9 volts each and the other two were at 3.7 v hooked up a 5 amp battery and charged it with in 5 minutes was able to put it on the charger and is accepting a full charge now

[@tensazero]

Battery drops below threshold. Can't charge on charger... but can still power drill... Meaning the drill can drop it even more... No protection circuit in tool or pack. That's not a good thing... Really bad design flaw.

[@RealToolReviews]

I will be testing this further to see what the issue is.....

[@bradnoyes7955]

I find this particularly interesting because I have the Porter Cable 18V Lithium tools and it does have the protection circuitry. When the batteries get low, the tools do not slow down, they just stop. if you pull the trigger again they usually have re-gained enough to drill/drive more but only a little bit before they stop again.

[@toysoldier46552]

I have the B&D Matrix tool 20v and is just stops running when the battery is low. I am not familiar with porter cable battery powered tools but do know they make a decent small jointer which I do own so I am sure this is just something to do with his unit, possibly a defect.

[@michaelfreeman5064]

Toysoldier b&d and porter cable are pretty much the same. the batteries are basically the same and most of the internal components are similar. since they are owned by the same company

[@toysoldier46552]

Michael Freeman Does the Porter Cable brand have a Matrix type tool? I do love the B&D version for that tool, it does so many small tasks that I would generally need several tools to accomplish and B&D has been known to be a bit more expensive because of the name actually.

[@jackbquick123]

Good thing the hot and ground are on opposite sides of the batteries you used.

[@johnmoore4822]

jackbquick123 I caught that as well, I’m afraid of all the other people that missed it as well, yikes 🤕

[@angleturner]

Yeah .. good thing... because it woulda been really hard to just cross the 2 wires over one another.

[@akesha4138]

Here are some tips You can hook up, with correct polarity only, an 18 or 20V battery to a car battery which is only 12 to 14 volts. It gives the higher voltage battery just enough of a boost for the charger to see that the battery can be charged. You can also use a 20V (high capacity 20V fully charged battery - 5.0 and greater only) to jump start your vehicle if the battery is low, not DEAD as that will cause the battery to be ruined. Ryobi 40V battery with 4 blinking lights - take the back off and look for RST for reset and short to the terminal next to it until the battery light indicator blinks, then place in the charger right away and mine did fully revive.

[@joemcmillan2089]

I have one lithium that the charger always indicates as bad when I attempt tp charge it after use. (yes, I gave it plenty of cool down time). I put this battery back in a drill, wire tie the switch to full on, let the drill run until the battery is completely drained - no light and no turn. Let the battery rest until cool and then put it in same charger. Charges to full no problem. This battery is over 10 years old and still provides good power and run time after the charge.

[@dakotad2690]

Thank you for this fix !! I had my doubts that this would work but I did as the video said and amazingly it worked just as your video said !@great video

[@snarknado7469]

Don't burn your house down! 😂 Seriously. Great video. Saving to hard drive. 😁

[@cajadeherramientasmx]

Excellent video Daniel!!!! Congrats

[@dadsworkshopbykipplabrie7982]

Got it, "Don't burn house down" LOL, Thanks for sharing and thanks for you're time. I just bought a floor model 60v battery from a Sears closing sale for $20, and guess what? its dead and wont take a charge! So I played myself because all sales are final, so wish me luck thanks again.

[@VG-rj8pn]

what the heck is a floor model 60 volt battery?????????????????????????

[@dadsworkshopbykipplabrie7982]

LOL, it was from a display model out of the box. The store was going out of business so everything must go, no returns no warranty just a roll of the dice. They were even selling CRAFTSMAN wall mounted banners and logos it was a mad house. Thanks for the reply.

[@ronaldlittle1598]

Thank you much I got Ryobi and DeWalt saves me money

[@marcplante4364]

This works, I had 2-24 v lithium batteries that had 1.6 and 1.5 v left, I did the trick and brought them back to chargeable

[@rpaull3]

And that means don't buy porter cable! My makita batteries have lasted me 15 years! I bought the original lxt kit with the mail in rebate for the sawzall!

[@waynenergy]

Damn ! ! I throw away my drill because my 2 battery is dead. I should have seen your video soon enough.

[@aggropa]

Amazing video. Your knowledge and ability to explain is really impressive.

[@craigbates3053]

Appearantly no or faulty LVC (low voltage cutoff) on the tool. This is sure to damage the cells if you continue to use it.

[@gordonconlogue5686]

If you don't do this then its useless anyway

[@jamesarrowsmith2517]

i watched this video and saved my battery it worked brilliant

[@ricksinger388]

Great video with emphasis on safety, but described method may be too conservative and outdated. While this may work as a quick and easy fix, chances are the current modern Li-Ion battery packs and their paired smart-chargers that first test, than determine viability status would be able to identify and resolve an issue that this would work for... Despite theories that battery-packs sales are a huge source of revenue for manufacturers, retail stores, etc... since most consumers don't register to satisfy the warranty... perhaps just a Conspiracy Theory to explain increasing battery failure rates??? Sometime all that is required is repeatedly inserting the batt pack into charger until unit senses enough voltage to charge the pack, since the initial test provides a small charge, but this can take MULTIPLE insertions, so best to check pack voltage to see if close to 75% of rated voltage. For a bit more advanced DIY viability test and resolution there are 2 significant considerations that may require additional advanced steps. Both require opening up the case, which can void any warranty as well as add more safety risk. This usually requires a special "safety" driver bit to remove the screws, one or more of which may be hidden under rubber seal or label. 1) If the source of failure is the circuit board or a non-battery component inside the pack, then NOTHING below will help. 2) But chances are there is one or more under-voltage 18650 Li-ion cells, which can be individually measured with a voltmeter once case is removed. If one or more is significantly measuring a lower voltage than the others (normal around 2-3.6V, below 1.5 V is either dead, deactivated by safety circuit, or hopefully just in "sleep" mode) which may be resolved by a trial of "boosting" the voltage with another 18650 or similar 3.5V power source, + to +,, - to -, for about 15-30 secs, small spark is OK. A confirmation of a potentially viable cell responding to a "wake up" is by showing any sustained voltage increase and eventually allowing it to be charged to 3.6V again. BE CAREFUL, and if voltage remains low or nothing, chances are it is not viable, either chemically or mechanically defective, possibly the safety circuit deactivated it, WHICH SHOULD NEVER BE MESSED WITH. 3) If a "boost" of one or more individual cell appears to be viable, the external "pack-boost" in this video may still not be effective as there may be components in newer commercial battery packs that prevents the inflow of power (transistors, MOFSET, etc ) using just the 2 external leads that may need a trial of being bypassed. To do this, find the part of the circuit board where the Neg and Pos aspects of the connected 18650 cells are making 1st contact. Measure voltage there and if still less than 75% of rated pack voltage, connect the charging source here (Again + to +, - to -) may confirm the bypass may be needed to provide charging of internal pack until smart charger detects an acceptable voltage and can provide complete charging , again a small spark is OK, but watch carefully. If internal voltage is below 12 V, consider use of a low current 12V trickle charger to get to at least that voltage. Test voltage here every 15-20 secs if not using low current charge source, be aware of any thermal increase in both batteries. Success is indicated by sustained voltage increases measured internally, then also at the external connections, eventually to where the commercial charger indicates the pack is viable and completes charging. If after trying these alternative reviving techniques you will either have a restored Battery Pack for either short or long time, or one to get properly discarded / recycled... or carefully harvest the parts for other uses. Strongly recommend searching for similar videos, especially of the batt pack brand you use, and BE SAFE!!!!

[@sickandtiredofbeingsickand]

What if my battery reads a full charge when connected to charger, but will not power a tool?

[@dorkxd2]

Thanks alot for this video. It saved me from selling my matco impact wrench. The cost of a new battery wouldn't of been worth it.

[@DC-go4nv]

Thanks for the explanation, a little long winded and a little dangerous, but you explain to do it outside and that should be sufficient warning. I checked mine and it was only outputting 1.5v, likely because I lost the drill and it was in it for about a year. Luckily I had a power supply around, set it to 14.4v and 1.5amps, after about 10 minutes the voltage was up to about 16v, the charger then took right back over like normal, so thanks again for doing the testing for us, it made me much more confident going through with external charging.

[@rosskrause3926]

What kind of power supply did you use ? "Power supply" is a broad term so not sure what you used . I have a Harbor Freight trickle charger,wondering if that would work safely ?

[@DC-go4nv]

@@rosskrause3926 I believe the generic term is "laboratory power supply". It's a testing unit that allows you to adjust the amperage and voltage output. You should only charge it up to what it can handle, but as long as you're not exceeding the output of the original charger, or at the very most the 18-20v it's supposed to support. You should be ok. Just remember, the goal isn't to fully charge it, just to get it over the threshold for the OEM charger to recognize it as a good battery.

[@coulombefrancois5371]

I just did exactly the same thing as you and it worked. I saved the battery!!Thanks

[@robertjahrling1877]

I have several batteries. You guys aren't joking are you?? PL reply

[@robertjahrling1877]

I don't want shit blowin up on me

[@swmplvr]

@@robertjahrling1877 4 months late but i can honestly say i just did it and it worked for my battery which was same as the one shown in video =)

[@mea7206]

Amazing video. Just sorted my battery out. Thanks

[@debohannan4315]

Sir you are mistaken what you are doing is dangerous to say the least the Li-ion cells are 4.2 each charged and should never go below 2.4 volts the cells are series to equal the voltage needed and say 5 series is for a 20 volt then they might parallel another 5 to those for double amperage or wattage . No 2cells are ever the same resistance so they will eventually discharge differently and if the balance gets off to much the charger will shutdown to keep from overcharging some to get to the full charged voltage in the pack, by jump charging you aren't fooling the battery or charger only yourself . If you want to fix the problem go into the case and measure each cell or group and only charge or discharge them to Ballance the pack then if that's what was wrong then you will have many more uses left in them.

[@BeanoNoir]

Be careful like he said as one of the cells could be dead with a similar voltage to what he showed. This will get the battery to charge, but it will likely have suffered a decent amount of runtime loss after undervolting so severely. It could also go Mt.St Helens. A safer method would be to buy an R/C style balance charger if you have multiple packs like this, open the pack, and charge the cells individually in a terra cotta pot (as they are cheap and insulate well) If it's a larger in parallel pack, things just got more advanced. You would have to disassemble the pack. The drill, and or pack in this video are likely malfunctioning and or of poor design, as an under voltage protection circuit should have literally switched the battery off (so that there would be no voltage at the probes, Methinks it's an issue with the pack itself, this also likely wouldn't prevent an overcharge if input voltage was high enough. Both can result in thermal runaway.) All modern brushless tools also feature over current protection that will automatically trip, just like a breaker if the motor is overwhelmed and calls for more current than is spec, whereas brushed motors typically only have temperature protection.

[@Thinker2-truth]

Lithium Batteries employ a BMS to prevent the batteries from catching fire. It is the BMS not batteries that most often fails. Either turning the BMS OFF (no power) or blowing the BMS circuit (damaged).

[@lifter98]

Good video. Clear and concise.

[@ooltimu]

You should be using a resistor in series when connecting the batteries like that or at least use one that't more discharged in order to have a lower current draw.

[@matthewberman7972]

Ooooh porter cable brushless 😁 I love my porter cable impact. I bet the new one is going to be fantastic!

[@mingohernandez6475]

It totally worked on my 20v lithium batteries . One battery was so dead it didn't turn on my drill at all . Charger was telling me it was damaged . Did what he explained in the video but for 10 minutes instead since it was completely dead . Put it on the battery charger and it said it was hot battery . It was warm after the transfer . But put it on the drill and it ran it this time . Next day once it cooled down I put it on the charger and it started charging the battery this time .

[@thegoodfight365]

So am I right to think that it's best to charge lithium ion batteries before they are completely dead. I use Ryobi & Milwaukee mainly and I have a brand new M12 2.0 battery in a brand new M12 impact driver and it blinked defective the 1st time i tried to charge it.

[@RealToolReviews]

Yes! Keep them fully charged & remove from tools when not in use.

[@thegoodfight365]

@@RealToolReviews thank you and I'm a big fan of your channel. Wonderfully priceless tips. You're really equivalent to having an industry insider virtually on call or living next door. 👍🏾 Thanks again.

[@AKJeeper]

This is what I've done to revive a few of my Milwaukee battery packs. My 1/2" impact gun has a tendency to run the batteries just below the charging threshold particularly when being used in cold weather. Sometimes it only takes a minute of 'jumping' the discharged battery to a fresh one to get the charger to work.

[@chaddelgado2590]

I have the v28 batteries I tested the volts with a meter it's says they're completely dead do you think this would work it's a Milwaukee by the way

[@jawharris]

Mine worked, and I did it indoors, took about 1.5 minutes.

[@Anti_Imperialism]

I just saved 80$ on black&decker batteries. Thanks

[@razorbackblood06]

Kobalt batteries have 3 prongs pos, neg, and I believe the other is a temperature sensor. I can't get a reading with the multimeter even the known good batteries though. multimeter confirmed does work.

[@kravenofspider]

How does one know if the battery has dendrited? How much life is left in a jump started battery such as that?

[@zeejimi4044]

I was able to revive 2 batteries in this way, but they did not charge for long, and they don’t last long when in use.

[@RealToolReviews]

It’s hit or miss

[@alphonsebreaux4735]

Your knowledge just got another subscriber

[@MrMoses28]

This really did work, thanks you.

[@geelongdrivingschool929]

It worked for me. Thanks mate, appreciated. 😇👍

[@thabangsenyolo370]

Thank you for your help

[@johnclarke6647]

Here is a question for you - Oregon 40 volt chainsaw battery. It is not running the chainsaw. It has 40 volts on it but the battery does not have any current in it. I connected it to a brand new charger and it blinks green but not a lot is going into the battery. What do you think?

[@jasonsgreen]

Thank you mr beast seems your solutions is on point.

[@frankthornal9489]

Can I do the same thing with what appears to be a completely dead pack ( does not turn the motor, but the LED does light dimly)? Or Don't waste time and potentially destroying the good battery?

[@vincentkille5105]

Mine was just all the way dead got a 20v off a buddy and only had them connected for probably 30 sec and it is working like new

[@phbrinsden]

Lithium batteries from reputable tool companies should all have battery management boards which monitor both charging, keeping charge rate under control and not allowing cells to go higher than about 4.2 volts, as well as monitoring discharge, not allowing cells to fall below about 3.0 volts or thereabouts. My DEWALT tools cut off when 20 volt max battery is about 15 volts or just under. If he can run that drill literally dragging forward then it is already too low and should have shut off earlier. Something else might be wrong so beware. Battery packs can drift down after a very long period of being on a shelf. Then this technique could be appropriate,

[@rhess10]

How do you determine the positive and negative on those batteries? Are they clearly labeled?

[@rhiantaylor3446]

This is a dangerous practice. Connecting two packs will result in a high and uncontrolled flow into the flat battery which is exactly what causes the sort of problems that have been highlighted with lithium batteries. If you want to try to bring a "dead" lithium battery back to life, it is actually necessary to use a low and controlled current of maybe 50ma. Usable Lithium cells will climb back up to the normal working range of 2.5v - 4.2v quite quickly with even this small, safe current.

[@RealToolReviews]

Read the comments and see how many people have successfully done this….

[@jiva3497]

So, if there is any current left in it at all and can run the drill then it's not a short? Just won't charge because it fell too low behind the manufacturer's setting. Wonder why they did that? Was it just a design to sell more batteries or is there some safety issue they had to be compliant with?

[@frodev728]

the marketed voltages 18v and 20v are not with load/without loud: 20v is the fully charged voltage and 18v is the nominal voltage - in other words the voltage half way between fully charged and fully discharged, or the “average” voltage.

[@RealToolReviews]

Fully charged = without load Nominal voltage = with load

[@axeman33333]

On makita, problem is there’s a circuit board that deactivates the battery regardless of what you bring voltage back up to.

[@MrCatfarmer]

I haven’t had this problem yet but I’m sure it will show up sometime. The problem I have is the batteries not holding the charge. Fully charged they drain as soon as I turn on the drill and can’t drill one hole before it’s dead again.

[@bentleyanderson4229]

I followed this exact process and blew out the B- post on my "good" battery. Now I have two bad batteries. I don't know what I did wrong, but I'm confident I did something wrong.

[@Landrew0]

Excellent video, done right. But all it not lost; when the battery voltage falls so low that it won't accept this method, there are still two possible options: In a fire-protected area, apply a current-limited charge (using a variable power supply, set to the rated battery voltage and a small trickle current) for about 24 hours. Then apply the normal charge. If that fails, the other method involves a much higher voltage and current to "shock" the cell back to life. In reality, the "shock" current burns away the crystals in the cell which may be shorting the anode to the cathode. This could either work, or result in a spectacular fire.

[@9UaYXxB]

Just no. Don't ever do this !!