Mycordless ryobi 12v drill battery not charging what can b problem

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.)

How long have you left battery on charger? It will take about 3 1/2 hrs to fully charge. t is probably not a good idea to leave the battery in the charger for long periods of time though, so once it is fully charged put it back in the drill. When fully charged the green led will turn solid. This link will have more info on charger and battery.
http://powertool.manualsonline.com/manuals/mfg/ryobi/130155001.html?p=2 C

YOU CAN GO TO GOOGLE AND DOWN LOAD THE MANUEL.JUST TYPE IN INSTRUCTION MANUEL ROYOBI CORDLESS DRILL 1048-67479CS LITHIUM BATATERY CB 120L YOU SHOULD BE ABLE TO DOWNLOAD THE MANUEL

I would think that a circuit is bad in the charger. Have you tried another battery?

Batteries are only good for about a year, if they are older than that, take them back to the store and see if they are guaranteed at all, (all Ryobi tools and batteries have a date code on them, and they are all guaranteed for 2 years, a little plug for Ryobi,) that is all I buy now days, they work great. So, to check your charger, you will need a volt meter set on 12 or 20 v dc, and see if the charger is putting out, if not, then, the cost of a new ryobi might be the same as the fix for the black and decker. That is if you use the thing, we use our cordless tools every day and charge them every night, hope this helps.

NO! Never charge lithium batteries in a charger designed for nickle based batteries like the NiHi your old charger was meant for. Ryobi did design the new Lithium charger to be backwards compatible so you can charge your older 18V NiHi batteries in the Lithium 18V charger.
Also note, NEVER miss-match the voltage, for example, make sure you are not trying to charge 12V batteries in an 18V charger unless the manufacturer has specifically stated that the charger is capable of multiple voltages.

Maybe one of the contacts is not contacting the battery contact.Are you sure it charges Lon batteries and not
ni- cad? No offense, just needed to ask.

Negative partner, you can try all day everyday but 12 v is 12v and 18 v is much more. its just not gonna supply enough juice to charge the battery. the most youll ever charge it is 12 v... sorry.

Are batteries for the dewalt cordless drill interchangeable? Will an 18 volt battery fit in a 12 volt drill?