Yellow / green light will not go off when charging

My Ryobi 18V One+ charger blinks green while it's charging. When the battery is fully charged, the LED goes to a solid green. However, one battery recently had a faulty cell. After several hours on the charger, the green and red LEDs both were blinking. That indicated that the battery failed late in the charging sequence. It didn't fail the initial testing by the charger. The other battery I charged that day charged fine.

The extended capacity batteries can take 12 hours to charge in my experience. The regular batteries take less time. The charge time will depend on the battery chemistry(The older NiCd batteries take longer to charge then the Lithium batteries.)

I hope this helps. Assuming you aren't dealing with a cold or hot battery or charging environment, if you have any suspicion about a faulty battery, replace it.

Cindy Wells
(Note: I have a 12V drill as well. Those batteries takes longer to charge for the same relative capacity than the 18V NiCd batteries.)

No, the P110, 18V NiCad battery charger, will not charge a 18V lithium ion battery. You need one of the dual-chemistry chargers. If you have the Ryobi ONE+ batteries, you can get the P117 charger ($30) or a charger with an extra battery (P126) from a store like Home Depot. A 6 battery charger and a 12V in-car charger are also available.

I wish that I had better news for you.

Cindy Wells
(who has the Ryobi 12V drill and charger, a few of the 4V tools, and a number of the ONE+ 18V devices and chargers. The single chemistry battery charger is not used much any more.)

The air holes on the bottom of the batteries are there for the battery to vent. Downside is, these vents can also allow moisture to get in and prevent contacts from letting the battery charge and causing the "defective" display on the charger.

I work on pool and spa equipment and I had dropped my batteries in a small puddle of water where I was working, both went dead immediately and both showed "defective" on the charger even after drying them out for a few days.

Tried using a can of air and gave each of the vent holes several shots... The batteries charged and are now working perfectly.

I'm sure even overnight condensation could be the culprit for a charger to display "Defective"

Do not try this since the charging circuit for lithium batteries are different than nicad! Improper charging of lithum batteries can cause a fire.

no, I would not try this. You can charge a nicd battery on a lithium-ion charger but not the other way around.

see if your charger is under warranty and have it replaced..yours is bad..

I have found when I put a battery on to charge and the green and yellow light turn on the battery is low voltage and the charger will not charge the battery ( bad battery)

if it is under warranty ,take it back .if it isnot then bite the bullet and buy a new battery ----try TOOLKING

Use
AC / DC Power Adapter Replaces Ryobi One+ Batteryhttp://lcdpayless.com/ryobi_one_power_adapter.php

Just was on a website for Ryobi drills and it states that if the yellow and green light stay on for more than 15 minutes the battery is fried. Couldn't find the link but if you do a search for Ryobi Drill 18 volt you should find the same info. It was as product review from Australia I think.

I also have a problem with the charging of Ryobi batterys. They seem to charge AOK with the green light coming on but the charge does not last at all. Not sure if the problem is with the batteries on the charger.