Usually, issues lie with tools, not the batteries that power them. But, the main word there is “usually”. Sometimes, there are still problems with the battery, which makes the entire tool useless.
Today, I’m going to be talking about something related to this. I had a Bosch 18V battery that was not charging, so I wanted to share some things that helped me so they can help others like you too!
I have made a video about how you can fix this problem. You can watch it before you read this article if you want.
If your Bosch 18V battery won’t charge the battery charger will blink a red light. To fix this issue, you may try to reset the faulty Bosch battery.
Related: Meaning of light on Bosch Charger
In order to do this, you will need another Bosch 18V battery which really works. Connect the positive and negative terminals of the two batteries.
Then, press the battery indicator to check if the power flows through the battery in balance. This should have reset the faulty Bosch battery.
In case you see a light with another color on your Bosch charger, I also have a video about it. You can watch below the different meanings of the lights on your Bosch charger.
Your Bosch charger can display 4 different light indicators when you connect a battery on it. It displays a blinking green when it’s charging a battery and this turns into a solid green once the battery is fully charged.
It displays a blinking red if it detects a bad battery and a solid red -for a hot or cold relay.
4 Methods To Resolve Your Bosch 18V Battery Not Charging
- Compatibility Issues
For those that just bought their Bosch 18V battery and it’s not working, I want them to check for any complications with compatibility. After all, not every battery works with every charger.
So, are you sure that your battery works with the charger you have? It could be that your current charger doesn’t support this battery, and that’s why it’s not charging.
You can easily find an official list online that tells you which chargers can work on your Bosch V18 battery. If you try to use anything else, it’s like that it just won’t charge.
I always used the official Bosch charger, so this wasn’t an issue for me. But, if you’re using something else that isn’t supported, that would explain why you’re encountering this issue.
The only way to get your battery to start charging again in this scenario is to use a charger it actually works with. But, if you already have a compatible charger, try these fixes instead:
Related: My Tips for Fixing a Bosch Battery Charger Not Working
- Clean The Charging Contacts
Contact pins are what connect your Bosch 18V battery to whatever is charging it. If these get dirty, the “contact” between both components will be much worse.
Ensure that the contact pins on both your charger and battery are always clean. When they aren’t, that stops the pins from meeting each other properly and prevents power flow.
This stops the battery from charging, which could be why you’re having trouble with your Bosch 18V battery. Luckily, all you need to do is clean these pins I’m pointing at below to resolve this!
The pins you see above are the ones on my Bosch charger. You’ll see similar ones on your Bosch 18V battery, so clean those along with the charger’s too to ensure there’s no fault on either side.
With the pins clean, restart the charger and try to plug the battery in again. This time, with a cleaner connection, both of them should work together and your battery should be charging!
- A Cell Inside Could Have Issues
Do you know the kind of cells that go inside your TV remotes, toys, and some other things like that? Well, a lot of batteries like the Bosch 18V actually consist of cells similar to that.
You can find these cells I’m talking about inside the battery by opening its covers. They’re all connected together and hold the charge that is transferred over to the tools you use.
Every single cell needs to hold a set amount of charge. Each of them works together to power tools connected to the battery, and if even a single cell has problems, the whole battery starts to fail.
That’s where I’m leading with all of this; your Bosch 18V battery may have a cell inside that’s developing complications. It may be something small like lower capacity, or the cell could be dead.
I took out the pack of cells inside of my model to show you what it looks like, and you can see me holding it in the picture above. Inside that covering, there are multiple cells that all hold charge.
The way to tell if any of these cells have gone bad is to further open the covering and use a multimeter on each one. If any of their voltage reads below the desired amount, you need to replace it.
Get a new cell of the same specifications, which you should be able to find online. Just ensure that they’re the right voltage and lithium-ion batteries, after which you can replace the faulty ones with them.
- The Battery Is Past Its Lifespan
It’s not always worth it to troubleshoot batteries too much or replace components inside them. If your Bosch 18V battery has too many dead cells or issues in general, it may be best to just replace it.
Most of the time, it’s best to replace one of these models after a few years of regular use. Their capacity will be much lower, the parts will be old, weak, and it’s better to get new ones to take over for them.
For people with older batteries, the ideal way to resolve this is to replace it. I have a relatively new Bosch 18V too, and you can see in the photo up there that it charges without a problem.
There won’t be any of the same problems, since it won’t have the same wear due to years of use. You can use it without a problem, and it should charge perfectly fine from now on!
