MOST COMPLETE GUIDE! Revive Ryobi 40 Volt Battery ~ The Easy Way, and the Hard Way! | Gears and Tech

[@GearsAndTech]

Here are the Tools you need for basic Repair: Security Bit Set - amzn.to/3HktJMS Paper Clips - amzn.to/3t67B3B For the Second Repair you will also need these items: DC to DC Step Up Adapter - amzn.to/3HhRzZI 12VDC 6A Power Supply - amzn.to/3MF5axc 14 Gauge Power Wire - amzn.to/3shQ9di Optional Tools and Supplies: Soldering Iron Kit - amzn.to/3LZn4va Alligator Jumper Wires - amzn.to/3hcNxH9 Volt Meter - amzn.to/3pgr809 Join the Gears and Tech Community Today: kzbin.info/door/87yYbCYEV-TqM9h6WU3Ccgjoin

[@salpatel7810]

Great video. Could you use the other good battery to charge up the dead battery? The good one is 40V and 5 amps

[@GearsAndTech]

I tried that and it didn't work. But, if you connect it direct the cells like I show in the video it should work

[@bigal1419]

@@salpatel7810 didn’t work for me either. In past I have been able to jump, but with this 40V no luck jumping 40V to 40V.

[@thdreefie]

I have the tools and converter you recommended but cannot tell from your video where the negative grounding point is located. Is it one of the screws on the circuit board or is it the mound of solder on the circuit board?

[@GearsAndTech]

It's the giant mound of solder on the circuit board You can also try to test for power between that mound and the positive terminal. If it reads power then you have the right 2 points

[@skipmenicos2511]

Thanks! Excellent guide to reviving these batteries. I was able to recover mine by resetting the controller. One correction: The security screws in my battery were T10-S, not T15-S.

[@cincocoates]

The RST reset option worked like a charm! My light blinked green once and it is now taking a charge again. Thank you!

[@jlg8689]

I used a 12v car charger that has power supply mode for the input and bought the little voltage booster/stepper and adjusted it to 35v. Now i have a chargeable ryobi battery thanks!!

[@rhiantaylor3446]

When you apply 35v across the battery, the cells will usually come back at the same rate and the battery voltage will rise to equal the 35v charging supply i.e. 3.5 v across each of the 10 cell groups in series. When individual cells really die, they usually represent a short circuit so charging current will still flow into the other cells. If this has happened, your 35v may represent more than the maximum allowed voltage across the recovered cells, because the faulty cells are shorted. If you have 2 or more dead cell groups, 35v represents 4.35v across the 8 "working" cell groups. This is dangerous. Chargers handle this risk by monitoring battery temperature and will turn off the charging current. The worst thing you could do is to leave the makeshift recovery arrangement active when you are not around to spot a problem i.e. a hot battery.

[@vkristof1]

The BMS inside the Ryobi 40 V battery MIGHT have cell balancing capabilities. IF it did it might be able to balance (equalize) all the cells as you charge the battery pack with the safety cut-off MOSFET defeated, which is what the KZbinr is showing in this video. I don't own any 40 V Ryobi batteries, so I have no direct knowledge of their internals.

[@ccbowers]

​@@vkristof1 They do have BMS w/ cell balancing, although I do hear complaints about its effectiveness. Also, counterfeits are out there, which complicates the safety of recommending these procedures.

[@mcmabry1]

Great info. I had to perform the reset four times because it would charge for about two minutes and then start flashing green/red again. Eventually it started completing the full charge after the four resets.

[@bluejayzion1550]

I’m having the same issue but not the same result. It’s keeps reverting to defective ideas?

[@TeranRealtor]

THIS is good info. I haven't even started any attempts yet - but I would probably give up after one or two tries if that happened to me. There is sometimes a value in stubborness!

[@jcbrenneman]

Great advice that saved me having to buy another battery or really another tool to get a cheaper battery. My battery would blink all 4 lights when I pushed the button, so I only had to go as far as the reset. One note that is a little hard to make out in the video: You must touch both RST terminals simultaneously. This is why he is bending the paper clip into an arc. I just used a staple. On my battery the first light blinked and I knew I was probably in business. Hooked up the charger and its-a-charging! I already had a set of TS bits from Amazon for ~$5, if I remember right. Annoying, but have come in common for a number of similar fixes.

[@Randy-zs8mg]

Thank you sir! Reset worked like a champ and it’s recharging once again.

[@GearsAndTech]

Glad to hear it helped!

[@katol1979]

Thanks ! Best video yet for this project. I was about to donate 2 of my 5Ah 40v! I just bought a buck step up/down 8A board off eBay. Can’t wait to renew the batteries. Thanks again.

[@GearsAndTech]

Glad it helped

[@robertsmelko9728]

I followed your video and all I had to do was reset this battery thank you you saved me $85 in the US

[@russelldeuell2703]

THanks for the tip on reset. I was able to check my battery and it had 5+V but would not charge. After using the reset terminals and leaving them jumped until the leds came on I was able to put it on the charger and start charging it! Thanks for the tip!

[@GearsAndTech]

Glad it helped

[@carlw9009]

Thank you for your thorough explanation of this procedure. Just this morning I had to take steps to investigate my one year old 40 volt battery and the fact that it was not accepting any charge. I had same issue with no receipt and the battery was purchased new in November of 2023! I figured as you did what could it hurt to open it up and take a peek inside and see if there was anything obvious wrong. Well I did everything that you did except for the ‘R S T’ step. Now I can readdress it again with a new step in the procedure and see if I can get the same results! Again thank you so much and keep the information videos coming! 🤔👍🏼😎👏

[@GearsAndTech]

Glad to help

[@sitbone3]

Just a tip I saw on another channel. When jumping the reset with a paper clip, push the black button at the same time. It worked for me and reset the battery. And, you can get a cheap torks security set at Harbor Freight for 7 bucks.

[@GearsAndTech]

Thanks

[@motorized2105]

Thx! The RST jumper step worked for mine! Time to get to work. Just for clarity for others, you have to touch BOTH of the "circles" at the same time, and look for the 4 green led battery charge lights to luminate.

[@paulreyes07]

what if it does not lit the 4 green led? what is the next troubleshoot?

[@zorst99]

I recently fixed 3 batteries a 30 volt and 2 18 volts but I was able to just use my car battery. I used 12 gauge speaker wire and I used some gator clips at both ends of the wire. It only took about 20 seconds with each battery to get them up to the point where the ryobi battery charger would charge them. You have to be careful using the extra power that a car batter gives you. I would have some leather gloves on when doing something like this in case the wires start to heat up you don't want to touch hot wires with bare hands. But it worked great and it worked very fast. Normally if you leave these batteries in the charger too long for whatever reason they will go below the working recharge voltage and ruin your battery. But if you get them before they have gone done too badly my method works like a champ. Using skinny gauge wires you would find that the wire will get very hot very fast.

[@hawaiianboi88]

You’re a life saver! Reset worked perfectly! I owe you a beer sir 🍻

[@N30Striker]

This is by far the best video out there on how to resurrect these annoying batteries! Thank you!

[@GearsAndTech]

Glad it helped

[@jviews1]

Call the 800 number with battery. they will want serial number to see if still in warranty period (1 or 2 years i forget). Got replacement battery and using it . Mind you, it should NEVER have failed. The Battery Management System should not allow discharge < 30 VDC and cells should not go bad unless they use bad/cheap cells to begin with. Excellent. Thank You.

[@Clint-d6w]

I just wanted to thank you for this video instruction. I followed it exactly and was able to bring back to life my old battery that I almost threw out 2 years ago thanks again.

[@GearsAndTech]

Glad to hear it worked

[@davidbray4380]

As I understand it, you said since your original battery was only at 1V, it was pulling too much current to go to 35V (as configured on your DC-DC booster), causing the display to blink; this however, still slowly charged up the battery over the day or so you let it sit. What if you just set the target voltage lower to begin with (say to 12V)? Would this then allow your setup to more "safely" bring it to 12V, after which you could then set the booster output to 20V, then 28V, etc, in order to progressively reach 35V? If so, would this be safer since the setup wouldn't be trying to push too much amperage, thereby remaining cooler? Thx for the video!

[@andyplana3504]

Thank you for making this video. I had two dead 40 volt batteries that would not charge even after trying the reset technique. I ordered the voltage booster you showed. I hooked up to a 12v 7 amp converter and in 2 hours I was good to go.

[@GearsAndTech]

Glad it helped

[@wynnpham631]

I just finished to build Ryobi 40 V charging apparatus based on your information, I will put the charger to work pretty soon. I encountered at least three different designs of batteries, two gave me hard time to locate the negative for by pass charging . I succeeded to reset one battery.

[@GearsAndTech]

Glad to hear it's working

[@asolano]

Thanks for this video. I had the same issue due to the battery being stored for too long. Your explanation about the ground contact and the positive bypassing the control board was the key for me. I used another battery (which I had previously opened to do a reset on) to jump the fully discharged one. It was probably a lot riskier than using the voltage buster card but I was able to get enough charge into the battery to do a reset and then it charged fine.

[@GearsAndTech]

yes, that is dangerous as there is nothing limiting the current. if there was a problem you could suffer an exploding cell. Glad it worked, but I cant recommend that procedure for anyone.

[@christopherleubner6633]

An old school battery charger with s jump start function can get the cells to working voltage quick. Bypass the control board and apply at the end of the plus and minus at the ends of the cell array. Charge till batteries are slightly warm, like lukewarm cofee. Then let it sit. Measure each cell voltage. If any are low volts remove and replace the bad cell. If it charges up to 3.3 to 3.6v per cell then go ahead and hit the reset contacts. Alternatively applying a current limited voltage in excess of the cell sum through a brake light bulb or similar will wake it up. The voltage forces the balancing and output FETs to switch on. Then charge as normal. A cheap 24VAC transformer plus a diode and capacitor works well.

[@brianring7226]

This worked great. My battery had the exact same symptoms. After following these instructions, it is back to life

[@GorillamansGarage]

I have the 40V 2.6amp Ryobi battery. Inside does not look lik eyours. I see no reset pins. My battery has 23V but all 4 lights are on saying its full. Also.. could I not just use the charger as the power source (+ & -) to boost it?

[@noegunn4303]

I Have a 34 volts 4-amp Ryobi battery for over 2 years and still going strong. four 18-plus batteries 5 years old. Regular charging works for me.

[@andrewdavie386]

TY. My 36V 4Ah battery was effectively dead, and blinking 4 lights on button press. I did the reset bridge with a wire held for a few seconds, at which point the green LED flashed once and subsequently showed one bar on button press. That's all I had to do. The charger recognised the battery once again, and now everything appears to be working as expected.

[@vics-videos]

The parts list is a gold nugget. Thank you for that!! One correction though: on my Ryobi 5AH 40V battery, the Torx screws have 6 "spines", not 5. The TS (Security) bits only have 5 spines -- mine have 6. That makes them THxx bits instead of TSxx bits. And my TH15 is too large, so TH10 is all that I have that fits. It's possible Ryobi has put different kinds of screws here, but just get a magnifying glass and count the "spines" in the screw and use TH bits if it is 6, and TS bits if it is 5. Awesome and very useful video -- thank you so much for doing it! Just saved me nearly $200 USD. Also, to reset the microcontroller, on mine, I found the the "through" labeled "RST", and there is another "through" right next to it that shows 3.25V. I had to take both ends of a small paperclip and connect them both at the same time. After about 1 second, 4 green lights light up at the end of the battery, evidently to indicate the reset occurred. (If they don't come on by themselves, you can press the button at the end to make them come on -- not sure if this is required for the reset to take place or not.)

[@GearsAndTech]

Thanks for your feedback. I haven't come across those 6 spline ones yet. I wonder if they switched what they use at some point?

[@josephsteffen2378]

There is another way of turning the Torx security screws: (1) Use a punch, screwdriver, or nail to break off the "security" pin; (2) Sometimes a tiny flat bladed screwdriver will wedge between the "security" pin and the drive sockets in the screw and the screw can be turned. I have a bunch of those Dollar Store "jewelers" screwdrivers that work fine. I can modify them with 600 grit sand paper (or a rock), to make them fit. I also have some tiny screwdrivers for my guns. They are very precise and engage screw heads securely. If you want some really nice screwdrivers: look for the gun manufacturers' or gunsmithing suppliers. They cost a few bucks each. I only use them on nice things. If any wear out, I can return the for a new one. Hey, you don't want screws to looked marred or stripped on yir Winchester!

[@vics-videos]

@@josephsteffen2378 Thank you for the tips! I may need to employ that 'cause I now have one with the Torx threads stripped.... **long sigh**

[@MillworkSigns]

Bypassing the circuitry and waking up the batteries worked on my as well. I was fortunate to have a 30v power supply. Took about 1 minute as the pack consumed a constant current of 3 amps. Back on the charger, now it's charging.

[@GearsAndTech]

Great to hear

[@jonathanchavez5636]

Thank you so much, the RST trick worked for me! Saved me $180!!

[@primefetus]

Great video! I'm going to attempt this this weekend. If all goes well, you're going to have saved me hundreds! I have four 4ah batteries that are dead. Thank you!!!!

[@GearsAndTech]

for sure, even if only half of them work itll be worth it!

[@samuelbaez2939]

Waoooooo...2years later this vídeo still doing a good help. Thank you man for that. Is going to be a very good help,I like the way you explain all through out the video.. Thanks ones again.

[@GearsAndTech]

Glad to help

[@MichaelBlackmon-p8r]

My battery is a 4ah 40V and the screw size was a T10 security. The T15 isn't even close to fitting and the T10 security bit was tight, not loose. Great video! All I had to do was reset and now we're off and charging again!

[@GearsAndTech]

Glad to hear it

[@thatracecameraguy]

This was EXTREMELY helpful. A simple reset seemed to do the job. X2. $240 saved

[@samueltucker8473]

Great explanation of how to reduce waste of valuable resources. Great content.

[@ORBrit]

Thank you so much for this! Using your logic of using a 35V plus source to boost the cells I was able to get my defective battery working using my working battery that was at 39V to boost the charge up to 36.5 on the defective one! Same method of just connecting + ve to +ve and -ve to the Gnd on the defective battery.

[@GearsAndTech]

Nice work!

[@PatTorti]

Thanks! You saved me headaches and $$$$$

[@TurpInTexas]

Great video, and excellent detail on how to go about resurrecting these batteries. I am quite surprised there hasn't been some sort of legal action about these batteries appearing to go bad forcing people to needlessly buy replacement batteries. And the overload/reset of the boost power supply was helpful since that is usually the way my luck goes too when I'm piece milling a solution for one of my problems, lol so thank you for leaving that in the video, it caught a potential snafu some people will encounter when they build up their restoration kit. Some of those boost supplies not only have a variable voltage control, but they also have a current limiting adjustment too, which would have fixed your issue with the overload/reset since you could have simply dialed back the current limit to a point the input supply could have handled the load without buckling. Cheers!

[@GearsAndTech]

unfortunately for Lithium batteries to be safe they have to have the charge controller be super cautious. If anything, this helps highlight how bad lithium is. Any lithium battery out there can suffer similar issues

[@TurpInTexas]

@@GearsAndTech Good point, and I suspect as time goes by there will need to be even more precautions taken as energy density per unit weight/volume goes up. I used to repair chargers for nickel cadmium batteries back in the 1980's, they used a simple thermistor bridge in the charger and another half was in the battery. As a discharged battery takes a charge, it absorbs the energy as a chemical reaction but once it has charged, that charging current gets turned into heat. The charger measures the termperture difference between the thermistor in it, and the one in the battery and turns off the charger once it sees the battery is getting warmer. Worked pretty well. I noticed the thermistor in the battery back, and I noticed once these batteries top off they seem to get warm too, so I guess they use a similar method for detecting the battery is charged. By the way, great suggestion about running that negative wire outside. I think I am going to try to find a way to install and wire in a small switch for the reset function as well since I would like to avoid opening the case all together. At the moment I'm trying to resurrect a practically new battery that got wet (just a couple of small spots of corrosion I was able to clean off), and I charged the battery with a couple of current and voltage adjustable power supplies that total 36VDC between them (in series) but it still doesn't seem happy. Worse case, I extract the batteries and test and replace them individually. I could buy a new battery, but where's the fun in that, right? Thank you for the follow up, may you and your family have a wonderful and prosperous New Year!

[@GearsAndTech]

You could go low tech on the rest. Just drill a hole in the case in line with the button and use a pen or small screw driver to push it when needed Cover with tape the rest of the time if moisture is a concern

[@richardvacanti9428]

There is nothing wrong with his battery that went dead. You should not be leaving his battery on the charger all winter. For storage of a lithium battery you should keep it 50% charged for the winter and not keep it on the charger and keep topping it off. This kills the battery. It’s his fault not Ryobi’s he was lucky to get a free battery.

[@chrhadden]

yeah really

[@mattvollmar]

Thanks a million for this! The reset just brought back a battery for me.

[@codester1989]

For anyone attempting to open their Ryobi batteries without a security bit screwdriver - I was able to "convert" all 4 of the Ryobi battery screws into regular screws by using a fine, flathead screwdriver to break off the little nub that sticks out (which makes it a security bit). Be careful not to hurt yourself by applying too much pressure on the flathead screwdriver as you try to break off the little nub, but it is a solution in a pinch with some security bit screws.

[@GearsAndTech]

Great tip

[@danthomas7812]

Fantastic! Excellent video, nice explanations. The "easy solution" (processor rest) did the trick for me. Security Bit set ($15) is worth it. Saved $180.

[@designstudio8013]

The battery is not $200 you can get them for $59 on special with a tool.

[@elijahdoering771]

This video saved me roughly $180 All I had to do was buy a torx security kit to extract the screws. The first trouble shoot “RST” worked for me Can’t thank you enough!!

[@GearsAndTech]

Awesome!

[@richardowens9061]

Thanks, for the video! This is exactly the information I needed for my own "dead" Ryobi battery. But, here are the lessons I learned: 1 - I should have gotten a different kind of electric lawn mower that would not have such a recurring problem. And, I regret my purchase. 2 - I will buy a new battery and keep the receipt and when the new one flakes out, like the old one did, I will expect Ryobi to replace it for free. 3 - I will just toss the old battery, rather than create a potential fire hazard by trying to revive it using this method. After all, I don't know why one of the two batteries went bad and not both. I may have an actual defective cell or cells. And, if I do, they should just be replaced. But, I am unwilling to do that, either. I am of the opinion that this sort of appliance should just work and have a reasonable service life. And, if it doesn't, I made a mistake in purchasing it and I should just learn from the experience and move on.

[@GearsAndTech]

I agree the poor battery performance is a show stopper for me

[@davidblake4925]

Thanks!

[@taz291819]

Worked like a champ, best $13 I've spent in a while. I'm sure it won't work, but going to try to revive my Phantom 4 battery using the same method (different voltages of course).

[@GearsAndTech]

In theory this will work on anything as long as the cells are good still

[@cfauvel]

any idea what a 4 light blink mean when I push the self test button? It is currently measuring 30 volts between ground and the first POS contact if I place it on the charger it says it is defective.

[@FarhanShaikh-d8b]

In the video you said connect the negative terminal of the battery to the Vout negative terminal but you are connecting the ground metal part of the battery to the negative vout part. Asolano mentioned in his comments too. Thanks for the in detail explanation that an non electrical person can do it.

[@GearsAndTech]

No problem. Glad to help

[@johnem4695]

you can use a small drill bit on the centers for the security screws. they will come right off allowing use of standard torx bits

[@GearsAndTech]

Yes. I've heard others do that too

[@mutt7780]

I've had 40V Ryobi batteries going on 2 seasons now, stored in a typical garage with temps from -10F-110F. At the end of the season i charge all batteries until the chargers shut off, then simply put them on a shelf, seems to work for me thus far. 6ahs, 5ah, and a 4ah

[@GearsAndTech]

I think the problem is leaving them in the charger

[@goaway3717]

@@GearsAndTech Just picked up their battery power station along with a couple extra 8Ah batteries to increase capacity along with a spare rapid charger. The instructions that shipped with the charger make it pretty clear to take the battery off the charger once full and if storing more than 30 days recharge them as normal every 6 months. My guess is they don't use the common 'smart' charging technology and leaving it on the charger fouls stuff up. It also suggests not storing above 80F or below 50F.

[@justpauls]

I just successfully reset a battery that had 34v with another fully charged 40v. battery. I connected the terminals with a jumper to the weak battery positive and direct to the ground for a few minutes, which brought it up to around 37v, did the reset and it is now taking a charge. It seems that resetting wouldn't work at under 35v. Thanks for the info, it gave me just enough information to be dangerous. (yes it's kind of sketchy with a jumper and that much voltage.) Be very careful with the loose ends.

[@BrBill]

This is such good info. I wish it worked for me, but I had 2 batteries completely unrecoverable. I can charge them this way and they act like they are charged, will power a device, but they would never reset and thus the Ryobi charger only ever shows the error code.

[@UpNfamish2]

Great. I have a dead 58v Echo battery n will try to pre charge it per your method n do a reset

[@darthlost]

After resetting, i get 39.5v across the master ground, i have 2 lights of charge. I put it on the charger and it does the flashing again. Would the boosting step be effective?

[@schilling3003]

I guess I should have looked at my battery before I went out and bought a set of security bits. Mine uses regular torx screws which I already had! I guess on the plus side I now have the set for the next time I need them.

[@steamcastle2473]

Your video was spot on, Got two batteries working again. thank you

[@AllAroundTube50]

The RST trick worked - you are a legend!

[@GearsAndTech]

Glad it helped

[@LowellStokes-jo4tx]

Well done! I don’t know if I have the patience to do all that, but I have the tools, thanks for sharing your expertise!

[@GearsAndTech]

Thanks for watching! Let us know if you give it a try

[@davidpower1843]

Opened my battery up and the entire ground side terminal block was COVERED in rust. Still had 1.9V when bypassing, so wire brushed as much rust off as I could and hooked er up. Only using a 3amp power supply so the display is flashing like yours, but voltage does seem to be trickling in. Hopefully no kaboom. Using a yellow female disconnect on the positive battery terminal and alligator clip to the negative solder blob. Temp seems stable so far - room temp on the battery and around 85° F on the voltage booster heat sink. 🤞

[@GearsAndTech]

Yep, give it till tomorrow and you may be good

[@guygordon2780]

This Works. A few cautions though (from a battery expert). Do not charge Li-Ion batteries when they are very Hot or very Cold (freezing). Charging Hot Li-Ion batteries shortens their life. Let them cool down first. Charging freezing cold Li-Ion batteries is dangerous. When you charge a Li-Ion battery, Li+ ions travel to the carbon/silicon anode where they pick up an electron becoming Li metal atoms dispersed inside the anode. Below freezing the Lithium cannot penetrate easily and may start plating the surface of the anode. This Lithium metal is highly reactive, and may cause a fire when warmed up or when you try to use the battery. Whenever you are charging Li-Ion batteries, If any cell in the pack heat up (as in too hot to touch) stop charging. Cells that fail this way cannot be fixed. The good news is that this is rare. Normally, Li-Ion cells are not discharged below 2.5 - 3.0V. But it can happen, and that's when the BMS board in the pack will refuse to allow charging for safety. It is actually dangerous to apply a full charging current of several amps to a cell below 3V. But you *can* safely trickle charge them. Buy a DC-DC converter board that features CC/CV (Constant Current/Constant Voltage). Set the Voltage Limit to 3V/cell (e.g. 30V for 10 cells in series). Set the Current Limit to 0.1A or less. Now you can safely charge even a 0V Li-ion battery. Let the pack charge slowly for hours. The slower the better. Think of it this way: you are shoving Li ions into an electrode that is severely depleted. Just be gentle and give them time to slowly move around and take up residence again. Once the pack is back up to 3V/cell check the voltage of each cell. If all cells are about 3V you can now safely recharge the pack to full voltage at the normal charging rate. Or you can just put it in the Ryobi charger to finish charging. HOWEVER, if your pack is badly unbalanced (e.g. 9 cells at 3.2V and one cell at 1V) then do NOT continue. You cannot safely force several amps into the low voltage cells. It's probably best to recycle that pack. Any cells that did not trickle charge up to 3V will always be too weak, and replacing one cell in the middle of a pack isn't worth it.

[@christopherleubner6633]

Yup unbalanced batteries are a recipe for fire or worse.

[@BooneDownSouth]

Thank you so much! I ordered the security bit set and the up convert thing and it worked like a charm. My battery is now on the charger taking a charge. Thank you for your help! That is awesome!

[@neillewis785]

HAD TROUBLE WITH THE SCREWS THEY LOOKED TO BE GLUED IN.ACTUALLY HAD TO DRILL TWO OUT.BUT I DID AS SHOWN ON YOUR VIDEO AND IT WORKED PERFECTLY ,AND SEEMED TO CHARGE QUICKER.

[@GearsAndTech]

Glad it helped

[@scottgardiner7418]

Simple reset worked for me. Charging it now....will see how it goes.

[@GearsAndTech]

Glad to hear it worked

[@waynekee8028]

Do you know what exactly you’re doing when you reset the battery? I’ve got a similar board to some of the other commenters. There’s a single “RST” thru hole next to a “3.25v” and a “GND” I’m wondering if the reset point is looking for ground or voltage? Thanks so much for this video. Very helpful!

[@GearsAndTech]

Ground. Short it to ground.

[@LS1007]

My problem is my Ryobi 40V trimmer battery is fully charged but stops working with three lights still lit. It will start again in a few seconds, run for a few more, then quit again and may not run anymore although three lights on the battery are still lit. Any suggestions?

[@GearsAndTech]

Your controller is bad, or you have a bad cell. Personally I think you have a bad cell. You could try to replace it, but likely not worthwhile

[@LS1007]

@@GearsAndTech Thanks for responding. I think it’s time for a new battery. 👍🏻

[@Internettumbleweed]

Yea my original 40v battery does this at half charge. The trimmer is definitely a beast and takes abuse with the brush head, but those batteries are just too damn expensive

[@KevinMcNultyTV]

Really nice job of explaining for regular/nontech folks...thank you!

[@GearsAndTech]

Glad it was helpful!

[@WoundmanTV]

Thank you for the video and guide! Works really well. However, I've noticed charging with a 12v 6a charger causes a lot of heat. Using a 12v 1a charger gives much better results. Thanks again!

[@PiZzAIVIoNsTa]

I bought a car battery trickle charger to revive some of my batteries. It does have different modes one being a 12v 1A. Is this what you used?

[@THEBILLPHIL]

Thanks! The charging method you used worked on my 40v Ryobi battery.

[@GearsAndTech]

Glad to hear it

[@tuckerbraddock492]

Tried this and it seems to be working, at least it’s charging now. I opted to bypass the security bit by taking a small headed punch and persuading the tip out of the way with a few hammer blows to the punch. Took off enough of the tip to allow a regular T10-15 to work. My circuit board has 2 holes for the reset. I used a paper clip to jump the two holes to do the reset.

[@GearsAndTech]

Glad to hear it's helped

[@CartoonMessLIVE]

Thanks! This worked great for me. I left it charging for 4 hours and it got it to 19v and then reset worked and it’s now charging on regular charger again!

[@GearsAndTech]

Great to hear!

[@willh3494]

Do you have to have the booster? Or is it safe to try without it​@@GearsAndTech

[@planetgreenpg9132]

Hello, I am trying to revive ryobi 40V 6ah battery. one line 5 batteries are showing only 1.4V whereas remaining 50 cells are 3.7v. I am checking if there is a way to charge those 5 cells without removing from the pack. Plz advise

[@dgautreau1]

It works, brought my aftermarket 40v battery back to life

[@JakeDalton-c1v]

I bought booster and computer charge cord and set up just like you did and no success. Ryobi 6ah battery started with 18v. Charged 24 hrs and discharged to 4v. Adjuster on booster was set to 35v and voltage to battery was 34.8v. Any idea what went wrong.

[@BlackLabelYettie]

Reset worked for me! Thanks for helping me save money buddy!!!!

[@GearsAndTech]

Happy to help

[@themanfromnantucket3882]

Worked for me 40v 4ah......got security bits Harbor Freight $6.99....soon as touched paper clip with electrical tape to rst holes light lit up....there was no push down.....was basically connecting two points together with paper clip......took balled up piece duct tape to hold down the hold down clip....slid in and out few times 7-10-12 seconds ..then plugged in and she's a charging again and think were on our way...THANK YOU.....all four my green were on before showing full charge...no after reset only like one/two lit up ...but charger is no green and charging...YAHHHH

[@Mi_Haggs]

QUESTION? I have a 40V 1.5ah DC Output charger from an old E Scooter. Can I just cut the plug off and use those wires instead of buying the step up adapter?

[@GearsAndTech]

Probably yes.

[@Feroce2003]

You won't believe this but all I did was use three wires with alligator clips on them ( I miss Radio Shack). I put TWO normal 9V (2") in series to get 18 V. I then connected the clips to the 40V battery for two hours, I wound up with 12V in the 40V battery then put it on the charger the next day I had 4 lights on the battery. I live in Michigan so I am use to bring the batteries inside until spring. All my other vehicles I have a trickle charger on them.

[@gideon59]

Kudos to You. Your excellent video saved me $179 × 2. Appreciate You!!!

[@GearsAndTech]

That's awesome! I'm glad it helped I just checked both my batteries and they are all the way dead again. So I'll be doing this again really soon

[@paparoysworkshop]

It is a good idea to test the cells (or groups of cells) individually first. Sometimes the battery dies because one cell is defective while the rest may be fully charged. I had an 18 volt Ryobi 1.5 amp battery that died suddenly. When I checked it, 4 of the 5 cells read 4.1 volts and one cell read 0.5 volts. A dead cells usually shorts, but they can die open also. After replacing the bad cell, the battery pack was fine again. If you have shorted cells in a battery pack and you force voltage across them, they can go up in flames so be careful. A lithium battery fire is not easily extinguished.

[@GearsAndTech]

When we check the voltage of the entire pack we are also confirming that no cells are open. If it was open we would have no voltage in the battery. Also we wouldn't be able to jump the battery like we are doing here because of that open cell. The only risk is if we do have a shorted cell. But since we are only bringing the battery above 30v there is very little risk even of causing issues with a shorted cell. The battery just won't reset, or it will discharge quicker than normal

[@paparoysworkshop]

@@GearsAndTech I'm not saying your technique is not viable, just other things for people to keep in mind. There are people out there with zero experience who get badly hurt because they can't or don't really understand what is shown to them. My comment was not meant as criticism, just additional ideas and information. I often watch channels like yours not because I have no knowledge of the topics, but because even after many years of experience, there are always new ideas and tips to pick up. So keep up the good work.

[@bradleyscott5296]

@gearsandtech - I followed the procedure and the battery is at 31v, but nothing happens when I short the reset, and the charger still reads the battery as defective. Is the battery toast?

[@tinabrunner2950]

This video was 100% spot on. Thank you so much for putting this on UTUBE

[@DonFrey-hy9eo]

I followed directions, got it up to the positive from the booster to the positive on the battery. I connected the negative on the booster to the ground on the battery and everything went blank. Now trying to charge with only the positive connected to the booster. Any suggestions??

[@dracyjenkins2919]

I have 2 replacement 40v Ryobi batteries that do not have the reset terminals. Any suggestions. Thanks

[@lylejameson]

@gearsandTech 1 year ago The circuit board opens the circuit when the voltage drops too low. So its not physically connected anymore. 12 days ago @GearsandTech when I use the multimeter on the battery terminals I get 3v, when I use the positive terminal and the gloop of metal I get 32v. Is this because what you are saying here, the circuit is not connected anymore? How does one re-connect it?

[@GearsAndTech]

True statement in both cases The positive circuit is opened up. But you can read from the negative terminal on the exterior of the battery and the positive solder point on the cells. This is where we are charging from as well The bms is on between that solder point and the positive terminal on the battery. And that's why you read lower voltages or no voltage at all

[@joeking433]

I have a 56v on a Mantis rototiller that I left either on the charger or in the tiller I forget now, but mine read 2 bars but when I tried to charge it it said full charge. So I used it down til it was dead hoping I could then charge it but it said it was already fully charged as well. Any ideas?

[@theredmoose]

My apologies if this is already answered. I searched but couldn't find my exact scenario. I used an old mac mini 18.5V and 6A power adapter. I soldered wire onto the ground. When I tried to charge it many times over the last 2 days and the following keeps occurring 1) The first time I plug it in after a long break the reading on the Converter starts ramping up. E.g. 12, 14, 19, 22, 24 then it just goes blank. 2) If I try to plug it back in and it shows 24V for a second then goes blank. Is there some safety shutoff in the converter or the adapter I am using?

[@soundtractorofficial]

I had the same problem, what I did was push it in and out, in and out of the charger, for about twenty minutes, it gives it a little spark each time, and I've had to do that about twenty times now, when it runs out all the way, you have to do that with my one. It sucks but it's still working.

[@GearsAndTech]

I tried that first. It never worked for me

[@KEVINLANGDALE]

Can you use the battery charger that came with the battery to boost the battery once the case is opened.

[@GearsAndTech]

I haven't been able to make that work

[@AKINGzhu]

When I open my battery the board itself has lots of corrosion, is there a way to fix it? Do I need to replace the board?

[@sasyfras264]

I have a 40 volt Ryobi battery. I have a different problem. It is fully charged and all lights blink at the same time but won't do anything.. I did reset still nothing. Can you help?

[@brian96597]

Totally editing my response. I don't think my circuit board is the same. The solder point in the video is a positive point. There is a large solder joint on the opposite side that is a negative. Connected ground to that instead. However on these two points the output is 36 volts? Battery flashes when pressing the button and has the same "battery error" when connecting to a charger. I also don't see any reset area on this board?

[@dougphelps6917]

Too early to tell if this is working for me. I have the battery currently charging on the step up system...and the voltage is slowly climbing. Thanks for this video. It is the most complete one I have seen.

[@spanielkopita9585]

To charge the battery, I'm wondering why we couldn't just wire it directly to the charger that came with it, still bypassing the board by using the ground terminal as you show?

[@GearsAndTech]

The charger doesn't output power till it successfully hand shakes with the battery It won't get the handshake when you bypass the bms Trust me, I tried everything possible to do this as cheap and easy as possible

[@spanielkopita9585]

@@GearsAndTech Thank you, that makes sense. My DC up-stepper and power supply will be arriving tomorrow. Thank you for your helpful walkthrough.

[@JayBirdyo]

Thank you so very much for this very informative video. One of my 4amp batteries was flashing all 4 lights, but wouldn't power my mower. Did the simple reset and then only 1 of the 4 lights came one. Put in on my charger and is now charging.

[@creaturecomfort5545]

I’m having the same issue with a newer 40V battery. It has two reset ports, so does anyone know how to do the paper clip trick with this version?

[@miroslavstanojkovic4123]

Hi, I bought all the necessary accessories and connected them like shown in th video BUT when I rotate the screw nothing changes. Voltage stays the same ,showing 19.6v I have been rotating the screw many many times but still nothing,it stays the same. So what am I doing wrong? I watched rhe video over n over and I am sure am doing it right but still nothing. Please if tou read this help. Best regards to you.

[@GearsAndTech]

Make sure the power in is on the right way to the voltage amplifier.

[@russwilliams6014]

Worked fantastically.

[@GearsAndTech]

Glad to hear it

[@jspriver]

I did this and it worked 100% thanks

[@dmosey870]

If you have voltage between the main + and - terminals, can you just hook your wires to those vs tapping the neg to the solder point? I'm getting about .5V there.

[@GearsAndTech]

No. The circuit board will stop the power flow

[@smokysniper7514]

I get a lot of these batteries very cheap and they have the similar issue. After the battery was charged I would reset it and would work but instantly go back into safety mode and the voltage would continue to drop any idea? TIA

[@dzw4826]

The link is not the same step-up adapter as what your using, doesn't have the switch for input and output. . The one I just received is also defective and the display didn't come on. I'll return and order another one. Hopefully #2 works.

[@GearsAndTech]

They are inexpensive so it's likely there will be quality issues. Some dead will be likely