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Is Your Ryobi 40v Battery Defective? Here's How To Fix Now

Cordless power tools are possibly one of the greatest inventions out there. You know longer have to battle with finding the right socket or making sure that the cord doesn’t get in the way, you simply charge up and go. But what do you do when the battery stops playing ball?

It can be infuriating, and a lot of people don’t realise that you might actually be able to fix them without having to spend money. Ryobi batteries are no different, these lithium-ion batteries are known to have their issues, but issues don’t mean that it can’t be solved. Here are the most common issues faced by Ryobi owners and 5 ways to fix them before you have to hand over your hard-earned cash.

Common Battery Problems

Unfortunately, no matter how good some tools are, there are small problems that can happen. Here we uncover the most common battery issues.

Ryobi 40V battery charger Flashing Red and Green

If your battery is showing red and green flashing lights, don’t panic! It doesn’t mean that your battery is done for it just means that it has been over discharged. This is where you have run the battery down and then left it and not charged it up. It could be that you forgot and left it on the shelf in your shed. Fear not though, this can be fixed.

Battery Entering Sleep Mode

One of the most common issues with the Ryobi batteries is the sleep mode. This is where you can’t wake the battery up to be able to get it to work. You can see the lights, you know it has power, it just doesn’t want to give it to you. Sleep mode is the most reported issue with these batters, so there are a few fixes for sleep mode, so don’t worry if the first one doesn’t work. We’re going to walk you through different ways to wake your battery up!

Temperature Fluctuations Resulting In A Dead Battery

Batteries aren’t known to be temperamental, but they actually are. You need to think of them as an energy source much like us. If they are too hot, they don’t work, likewise if they are too cold. These temperature fluctuations can damage the way the battery holds energy. This causes the battery to look as though it is dead and lifeless, but that may not be the case at all.

Micro Charges

Instead of throwing it out the first thing you need to do is give is micro charges, all you’re going to do is plug the battery into its slot for a few second and then take it out. These short sharp bursts of charge will wake the battery up, but you will need to do this for around and about half an hour. Don’t be deterred though, this can be the difference for you paying for a new battery and not!


One of the easiest things you can check once you have tried with the micro charges is checking of the terminals. These are the pins that plug into the battery and vice versa. Overtime these can become dirty and clogged. Make sure you unplug everything before you start cleaning and use a dry cloth or alcohol-soaked wipe. This will pull off all the dirt and grease that is blocking the ports. You’ll be horrified at the amount of build-up that comes off the terminals!

Charging Temperature

As much as we’d love them to be, batteries aren’t invincible and they can actually be quite temperamental, especially when it comes to temperature. Just like us, batteries operate best when their temperatures are kept in a comfortable range. Sometimes, it can be hard to keep the temperature of a battery constant, especially if it has been kept outside in your shed.

You need to keep your battery in a temperature range of between 5 degrees and 45 degrees. If it bounces around too much between these variants, you can have a problem with it either not wanting to charge, not wanting to hold charge or going into sleep mode. If this is the case, simply bring the battery inside and let it sit so it can balance at the ambient temperature of your room. This may take a while, so leave it for 24 hours before you start charging it again.

Sleep Mode

You may find that your battery is still in sleep mode and if the first two approaches haven’t worked, then maybe this one might. Sleep mode occurs when you have the battery too low and it has become almost empty, which is then compounded by the fact that you may not have put it on charge after it died. This results in your battery going into sleep mode. If the micro charging approach didn’t work, you may well need to get slightly more technical. Grab another battery of the same type and connect them up. Make sure you don’t get this wrong though otherwise you risk damaging both of the batteries you are connecting up. Simply connect the contacts, positive to positive and negative to negative. This will charge the battery up very quickly, so you will only need to leave it on for 5 to 10 minutes. Once you have reached the allotted charging time, simply plug the battery back in and away you go!

Get Your Tools Out

Some of you will have access to a multi meter, these devices measure current that is passed through equipment. If you have one, it is a very quick way of determining if your battery or charger is faulty. Plug the charger in and use your multi metre as directed, you should get a reading of at least 18v, anything below this signals a faulty charger. Once you have confirmed that your charger is ok, move onto the battery. You should be seeing readings of at least 7 volts. If you aren’t seeing this, then your battery is in sleep mode. Begin the micro charging cycle and then test after half an hour. If the battery is still showing lower than 7 volts, it may well be time to admit defeat.

Admitting Defeat

Sometimes, no matter how much we try, we just can’t bring our old batteries back to life. If this is the case, don’t panic, simply find your nearest Ryobi distributor. All Ryobi batteries come with a three-year warranty, so it will be worth checking if yours falls within that category. Before you head out to the store, it’ll be worth finding the receipt for the original purchase. If you are out of warranty, it will still be worth taking your battery in as the store will be able to dispose of it in the correct manner. You don’t just throw batteries into the bin; this needs to be done the right way.

Final Thoughts

Having cordless tools sometimes means you are faced with the unenviable situation of potential battery failure. Ryobi batteries are no different, but thankfully there are ways to make sure whether or not it is past the point of saving. Follow our 5 tips to try and restore your battery before you throw it out, because they might just work!

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