“I left my Milwaukee M12 battery on the charger overnight by accident. Help! Will my battery be fine? Is it safe to do this? Will it explode?”.
People say it’s a bad idea to leave things on charge overnight. What exactly does it do to an M12 battery though, and is it truly so bad? Let me answer that!
Read: Common Milwaukee M12 SDS Rotary Hammer Drill Problems Troubleshooting
I also have a short video about this topic which you can watch below.
Here, I left my Milwaukee M12 battery on the charger overnight for it to be fully charged. The next day I got a fully charged battery.
Based on the official Milwaukee product manual, leaving the Milwaukee M12 battery on the charger overnight is safe. There is no risk of exploding or catching fire.
However, it’s recommended to unplug the Milwaukee M12 battery as soon as the it’s fully charged for good practice and to maximize the its lifespan.
“I Left My Milwaukee M12 Battery On The Charger Overnight – Will It Be Fine?”
I don’t know about you guys, but I grew up regularly hearing that it’s terrible to leave technology on charge overnight. Family, friends, and pretty much anybody else would say it’s a bad idea.
I’m sure you’ve heard something similar, right? After all, that’s probably why you’re here in the first place. Well, let me put you at ease first; don’t worry about the Milwaukee M12 battery.
It was actually true at one point that charging things overnight isn’t a good idea. That was quite long ago, though. Well before modern technology made batteries more durable than ever!
So, to answer the question…
Will It Damage My Milwaukee M12 To Charge It Overnight?
Nowadays, lithium-ion batteries like the ones on your Milwaukee M12 aren’t prone to overcharging! They’re built with failsafes that prevent major complications from excessive charging.
Related: Tips for Fixing a Milwaukee M12 Battery Not Holding Charge and Not Full Bars
However, that doesn’t mean it won’t damage the battery at all. Charging a battery all the way to 100% is actually bad for it, as that puts extra strain on the battery.
In case you’re wondering if your Milwaukee M12 battery is still good if you charge it overnight, I have a video here which can help you determine that. This is about the different Milwaukee M12 light codes.
If you put your Milwaukee M12 battery again on the charger and the indicator lights display a solid red, it means it’s charging. This will turn into a solid green if it becomes fully charged.
However, it’s not good if you’ll see a flashing red and green because this indicates a bad battery. The same thing goes if it’s flashing red only which means a hot/cold relay.
And in case you want to know what should you do if you see a flashing red and green on the indicator lights. I also have a video about how you can troubleshoot this problem.
In the video below, you’ll see how you can reset the Milwaukee battery. You would need another similar healthy battery.
Using two wires, connect the positive and negative terminals of the two batteries. Then, leave it for around 15 seconds and disconnect it. This will reset the bad battery.
The same goes for letting a lithium-ion battery drain down all the way to 0%. In short, it is a little bad to let your Milwaukee M12 battery get to 100% or 0% health.
Related: How I Solved My Milwaukee M12 Battery Shows Green but Not Charging to Full Problem
Damages that arise as a result of this are minimal though. Sure, it does damage the battery and put a big strain on it. They’re manufactured with this in mind though.
Users don’t need to micro-manage every single one of their Milwaukee M12 battery’s charging cycles. It isn’t necessary to stress out about unplugging it from the charger before 100%.
Since they’re pretty much the same thing, the same applies to leaving it on charge overnight.
While it certainly is true that avoiding overnight charging (or 100% charging in general) is better for the battery, the advantage isn’t that drastic. At most, it extends the battery’s lifespan a little.
For an extra few weeks of better performance, I don’t think it’s worth micromanaging the Milwaukee M12 battery’s cycles. Instead, you could just take care to not let it drop to 0% often.
Even just that will be great for the battery, and extend its lifespan. So, to answer the main question you’re probably thinking about…
Should I Charge My Milwaukee M12 Battery Overnight?
It’s good practice to avoid putting things on charge overnight if you don’t need to. After all, like I said, it is better for the battery if users don’t charge it to 100% regularly.
But, if you have work in the morning and need the Milwaukee M12 battery for it, there’s no huge harm in charging it overnight. If you’re asking me, I think it’s more than fine.
The battery isn’t at any immediate risk if left on charge overnight. Leaving it on charge across the night and storing it away when it’s at 100% pose the same harm, so don’t stress out about it.
Whenever you need to charge it overnight, let your Milwaukee M12 battery sit on the charger overnight. I do it myself now and then, and I’m sure many others do as well.
If the lifespan is a concern, just avoid letting the battery reach 0% battery and don’t store it when it’s at a 100% for longer, better performance!
