Review on DEWALT 18V 20V Adapter DCA1820 by Jeremy Yuusuf

THE GOOD: Matches a 20V lithium battery to 18V tools as advertised. : Completely drains the lithium battery in just a few days if left on the adapter. The battery must be removed from the adapter after each use. I am thinking of hacking the adapter and bypassing the circuit load that is causing the leak. There is nothing to prevent an 18 volt tool from being operated with 20 volts without an intermediate circuit. UPDATE 9/17/18: I've deciphered why these adapters are draining the batteries. Inside the adapter, DeWalt includes circuitry that detects when a NiCd charger is connected and, if detected, disables the pass-through circuitry in the adapter. Without this feature, a lithium battery pack can be exposed to incorrect NiCd charge parameters with catastrophic results. Unfortunately, the detector circuitry has an annoying flaw, as it keeps draining the connected lithium battery, even when it's not connected to a charger or tool. As a result, the batteries are empty within a day or two. DANGEROUS! MASTER ROBINSON - DANGER! From a faulty adapter to a deadly one, the Chinese knockoffs have the look and feel of a DeWalt DCA1820 but no safety circuitry inside, just wires straight from the battery pins to the drill pins. As long as lithium batteries are being charged with the DeWalt Lithium Battery Charger, you are safe and the tools will function normally at 19 volts, the actual open circuit voltage of a charged DeWalt lithium battery. However, if the lithium battery pack was connected to the NiCd charger with an adapter - grab a beer, pull up a chair, sit back and wait for the show.