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

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: ru-vid.com/show-UC87yYbCYEV-TqM9h6WU3Ccgjoin

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! 🤔👍🏼😎👏

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.

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.

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.

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.

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

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!

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.

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

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

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

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

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

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

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.

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

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.

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.

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!!!!

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.

I did this and it worked 100% thanks

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!!

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

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

The reset trick worked. Thanks 👍👍

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

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

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

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

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!

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.

The RST trick worked - you are a legend!

You are a great communicator. Thanx for the info!

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!

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.

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.

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.

Worked fantastically.

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

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.

Worked on my battery packs I have all the tricks for dewalt and Milwaukee battery packs thanks

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!

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

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.

Worked great for me, thank you so much!

Easy fix - hardest part was finding a TS 10. Thanks much!

Exceptional video sir.

The reset work for me first try, thank you!

Excellent video.

Thank you for the tip to contact Ryobi, which I did do after watching your video and they are going to send me a new battery which thanks to you and your great advice saved me a few dollars which is very much appreciated

dude you just helped me reset and fix my battery! thank you!!

Your video is the type that I always subscribe to, well done! I have a 40 volt 6Ah battery that when I hit the test button only the left-most light and the 3rd from the left light up only. I didn't realize when I bought it that is was a RECON battery! My question for you is this battery toast!???

Great job thanks I’ve subscribed because it was helpful easy to understand I have lots of Ryobi battery operated tools with a few batteries doithis thanks

Reset worked for mines!!!

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).

Great video. Very good practical help with these frustrating Ryobi batteries.

It worked! Thank you!

Great job thank you. Dont need to do yet but least i know now. At goodwill they usually have a boat load of laptop chargers. For Dmm volt meter harbor freight has cheap one for around 5 to 7 bucks..thank you

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

It was great to hear this info from an actual electrician.

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

Thank you so much!!! I used a USB charger for 5V power supply

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.

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.)

Really needed the link for the voltage converter.

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!

You save me a bundle on a new battery, thanks so much!

Thank you for doing this video. I just ordered the stuff off Amazon that you suggested and look forward to fixing most of theses batteries sitting around. Appreciate your time!!👊🏻👊🏻👊🏻🇺🇸

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.

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!

great video! I used your link to get the DC converter I hope it helps your channel and I subscribed 👍

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

I rarely sub, but I immediately liked your style, so I subbed!

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!

LOVE THIS! GENIUS!

Good tips when you jump reset, at the same time, press the reset will do the trick without holding 30 seconds

Thanks!

The reset truck worked!!!!!!

Excellent!!

I found your video informative. I will definitely be subscribing to your channel.

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.

Excellent , clear and thanks for tool llist

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.

The Model OP4015 battery that came with my 40V chain saw in 2014 shows 3 lamps. The saw then runs a run-stop 5-second cycle. I thought I would ask the local Home Depot store whether they can test the battery. (Ha ha ha!) I figured if the battery is bad, I'd simply buy a new one. Ha ha ha, again. At least $179. Thanks for the repair course, and the list of tools.

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!!

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.

Ok got your charger board and power supply , and clips from this video. I have 1 original Ryobi battery and 3 after market batteries. We had a (gasp) cold snap in Florida and took all 3 after market out. All of the after market have no reset so charging my first one for an attempt. Wish me luck.

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.

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.

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

Thanks man you're a genius 🎉🎉🎉🎉🎉

Nice video, i got a question: I have bougth a lot of new 36v 1,5A ryobi, the are produced in 2018 and when i unbox them the voltage is 0 to 3 v and no light in any bar. i can charge the normaly and they work fine, but when i measure the voltage it says 19,3 V but all green bars are on ?

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.

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

This is a great help! Thanks :-)

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!

I have been over this several times and feel I understand it. saved 1, 5A battery , thank you. Please send a link to the dc to dc step up adapter you are using, you mentioned it would be here but after hours of looking, I just can't find it.

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.

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