You added a plus to my knowledge in those Ryobi Batteries. I installed a new cell into a pack and yes my cell was fully charged higher that the other 4 so it would not charge. Thanks!
I have a 18V Lithium 4Ah. All my batteries show 4.01. Is that normal? I plug it into the charger and I get a solid green light but the the LED lights on my battery do not flah or lumimate. Thank you in advance !!!!
These cells typically go from 3.0Volts when “empty” up to 4.20Volts when fully charged. If the voltage drops below 3.0Volts, the BMS board might shut down the Mosfets and not allow the battery to be charged. You can charge the cell manually with a power supply set to 4.20Volts, 200mA of current. Bring up the Voltage on the low cells to match the others. Then use the Ryobi charger to finish charging the battery.
I got battery that got left out in the rain. Couple of battery contacts are rusted. Would it be worth it even try resurrect it? I would have to buy a voltmeter
After three days searching for an answer to my problem, i finally found your video. Thank you. My Ryobi P107, 1.5 Ah battery was only showing two lights although the charger said it was charged. Putting it in my leaf blower, it only lasted a couple of minutes and went dead again. The five cells tested 3.71, 3.72, 3.73, 3.83 and 4.22 volts. I'll try tomorrow to get the two high ones back down around 3.70 volts and see if that does it. Thanks again.
thanks for your explanation, it is very helpful. but my problem is a little different, I cannot take cells out of battery, it seems to have a glue in bottom of the case, anyone can give me advice ? (my battery is a kickoffs from amazon, P-108 5Ah.)
Basically, this is balance charging of a lithium ion battery. This is a common method to maintain a electric RC car battery which usually provides 12 V with multiple cells series connected. On the other hand, you can purchase those balance charger for RC cars and make a 5 cell connection cable to re-condition those power tool batteries. Look for some 5S connectors for 18V (same as 20V max) batteries. Those RC battery balance chargers has a plug in for those (2,3,4,5,6)S connectors, usually. You have to do this battery re-balancing periodically (like once a few months at least) to maintain the best condition for the battery pack. But those power tool companies do not sell those batteries with balancing input while RC batteries usually come with those ports and chargers as well. Exception is DeWalt, as far as I know a DeWalt Li-Ion battery has contacts for individual cell. But DeWalts also suffer from balancing as well. Which means the chargers do not usually provide balancing... I'm not sure why power tool companies do not provide balancing chargers officially. 🤔
Well explained especially the fact of ensuring that all the batteries should be approx. 3.7 V. This is what has been missing from the other explanations.
Typical Li-Ion 18650 batteries are safe with 3.4-4.2 V of voltage range, depending on charge in each cell. Lower than 3.4 V, the battery will go kaput if not charged soon. Above 4.2V, it may burn!
Will the circuit boards limit the amount of cells I can wire in series? If I have the carcas of an old 1.5 ah battery can I modify the housing to fit 15 or 20 cells and build my own 6ah or larger battery?
That's what I have to do. I was trying to bring up the low batter up to the higher cells. (I thought 4.2 volts is a bit high.)The low cell was 1.8- forgotten exactly what, but I know now to take the others down. 😊 Thanks! Yours was the video I was searching for! Cheers man! Very pleased. I had another that was all flat and charged it with 12 volt supply over the main battery terminals (at the cells,) for a short time (30 secs odd,) to bring the whole thing above threshold as a surface charge only and then put it in the charger. It charged and worked like a charm. The battery's full zap now and runs my impact wrench awesomely!
Is easier to just bring all down to same voltage and just let them charge and balance at the same time. I'm glad my video was able to help you some how. Thank you for your comment!!
After doing so much research & watching so many of these Ryobi 18V battery repair videos… I thought this was the one! lol.. You were having the same issue that I am… Testing the battery at the stem/charging terminals shows .5 V… Testing at the contacts inside the casing once the battery is disassembled, showing 14 V… unfortunately, every single individual cell shows the same 2.7-2.9v.. any ideas as to what could be the issue?? Btw- mine is the 4ah 18v Lithium ion+ .. so there are 10 individual cells inside. Any help would be greatly appreciated! I have two doing the exact same thing… I’ve only taken one apart, but I’m assuming it’s going to be the same issue… Thanks so much in advance!l
chiiiiingon! i've seen plenty showing a low battery but never one were they were too high. great job explaining and even better showing using the drill/tool to safely discharge the cells. great job!
I have put the battery to the test since i fixed and it has been working great, no more issues at all. Thank you for commenting/asking, really appreciated!
Wowww... another very nice video, this helps me a lot, my battery slow charging and fast discharge, and i will try to copy you... hopefully i can fix mine too... thank you so much...
This exact thing happened to my DeWalt battery a while ago, but I got rid of it without knowing. If it happens next time I know what to look for. Thanks for sharing!
Awesome dude, i had the same issue with 3 of my batteries and i was about to dispose them. then I came across this video and i got two of them back to work, THANK YOU very much for shearing your video saved me money lol!!👍👍🙌
