Hi there! You can use any M18 battery with any M18 product. However, you will typically get a longer run time when using a larger amp hour battery.
All milwaukee battery charger 18 volts, 12 volts or dual are all compatible with all milwaukee.
Return it back to where you bought it or contact Milwaukee for replacement
Yes... All m18 chargers charge all m18 batteries
Well first contact Milwaukee, and notify them of the problem you having, see what they say. Its most likely the battery's might have some bad cell's, if you have an multi meter you can test each battery to see what voltage you are receiving. And after that you can open the case and check each cell ( let me remind you contact Milwaukee first before attempting this because if you open there devices, you voided the warranty) and replace what ever cell that is bad, you can find the battery cell's online
Hi there! You can use any M18 battery on any of our M18 products.