400bird
Solar Wizard
I've got about 7 Milwaukee M12 batteries. This morning, one 6.0ah battery failed to charge and the charger started blinking alternating red and green LEDs. The symbol on the charger reminds me of a broken heart, but a battery instead of a heart. You can see the led key on the charger below.
I decided to get some voltage readings and found a 0.7 volt delta between the cells.
C1 = 3.7 volts
C2 = 3.0 volts
C3 = 3.65 volts
Well, I've got a iCharger X8, I can fix that!
Then I realized I also have an M12 charger that I never use. So ummm, tada!?
+
Ugh, that pic sucks, but you get the point. Balance charger bodged into a real Milwaukee socket. The Milwaukee charger still has the 120vac plug, so it should work, but here it isn't plugged into the wall and is mostly just providing a connection point for the balance charger.
That first pack balanced nice and slow over a few hours while I was doing something else. I unplugged it before it finished to go make dinner.
After dinner, I decided to check the balance on all the other packs.
![1698039135720.png 1698039135720.png](https://diysolarforum.com/data/attachments/173/173691-2e75f550133931926d54f55eeccbe6d1.jpg)
![1698039148539.png 1698039148539.png](https://diysolarforum.com/data/attachments/173/173692-6342f28d0724aaaee99b24448f307cb1.jpg)
![1698039161710.png 1698039161710.png](https://diysolarforum.com/data/attachments/173/173693-8048fbf5830d8e73f404cb90f1519e75.jpg)
![1698039174378.png 1698039174378.png](https://diysolarforum.com/data/attachments/173/173694-f190e4e88644c05fefb60817fdc381e3.jpg)
![1698039191119.png 1698039191119.png](https://diysolarforum.com/data/attachments/173/173695-d7253ffdd50eb6fd402ed104a2ef66f0.jpg)
![1698039220169.png 1698039220169.png](https://diysolarforum.com/data/attachments/173/173697-c05bdb3fcfc4de065259651ea06c401b.jpg)
And I think this was the best pack. Guess what's going to be sitting on the table in the office balancing cells all day tomorrow?
![1698039207083.png 1698039207083.png](https://diysolarforum.com/data/attachments/173/173696-67833fbfa97c2cd42368a3bc750653fe.jpg)
Anyways, it sure does seem like Milwaukee M12 batteries don't do any cell balancing.
Just out of curiosity, I opened a single M18 battery, the cells were 3.886-3.889 volts, so a much better BMS in the M18.
I decided to get some voltage readings and found a 0.7 volt delta between the cells.
C1 = 3.7 volts
C2 = 3.0 volts
C3 = 3.65 volts
Well, I've got a iCharger X8, I can fix that!
Then I realized I also have an M12 charger that I never use. So ummm, tada!?
![1698039017915.png 1698039017915.png](https://diysolarforum.com/data/attachments/173/173690-27b459d4c4099d2dcd862d2463557e87.jpg)
Ugh, that pic sucks, but you get the point. Balance charger bodged into a real Milwaukee socket. The Milwaukee charger still has the 120vac plug, so it should work, but here it isn't plugged into the wall and is mostly just providing a connection point for the balance charger.
That first pack balanced nice and slow over a few hours while I was doing something else. I unplugged it before it finished to go make dinner.
After dinner, I decided to check the balance on all the other packs.
![1698039135720.png 1698039135720.png](https://diysolarforum.com/data/attachments/173/173691-2e75f550133931926d54f55eeccbe6d1.jpg)
![1698039148539.png 1698039148539.png](https://diysolarforum.com/data/attachments/173/173692-6342f28d0724aaaee99b24448f307cb1.jpg)
![1698039161710.png 1698039161710.png](https://diysolarforum.com/data/attachments/173/173693-8048fbf5830d8e73f404cb90f1519e75.jpg)
![1698039174378.png 1698039174378.png](https://diysolarforum.com/data/attachments/173/173694-f190e4e88644c05fefb60817fdc381e3.jpg)
![1698039191119.png 1698039191119.png](https://diysolarforum.com/data/attachments/173/173695-d7253ffdd50eb6fd402ed104a2ef66f0.jpg)
![1698039220169.png 1698039220169.png](https://diysolarforum.com/data/attachments/173/173697-c05bdb3fcfc4de065259651ea06c401b.jpg)
And I think this was the best pack. Guess what's going to be sitting on the table in the office balancing cells all day tomorrow?
![1698039207083.png 1698039207083.png](https://diysolarforum.com/data/attachments/173/173696-67833fbfa97c2cd42368a3bc750653fe.jpg)
Anyways, it sure does seem like Milwaukee M12 batteries don't do any cell balancing.
Just out of curiosity, I opened a single M18 battery, the cells were 3.886-3.889 volts, so a much better BMS in the M18.