Cordless Tools and Chargers

[variflexpghpa]

I have noticed that the transformers for the battery rechargers for cordless drills, saws vary in that some have an AC output while others have DC. Since the batteries are all DC voltage, why is there this difference ? Any info?

Thanks

 

[sudsmaster]

All batteries need a DC voltage to be charged. AC would charge and drain a battery at the same time.

The AC output listed might be an intermediate transformed AC that is regulated to a DC voltage.

 

[variflexpghpa]

Which means exactly???

So would that mean there is a diode within the transformer which makes the AC now DC?

 

[toggleswitch2]

Yes. I think what I am reading is that all electricity to charge batteries needs to be DC. If the transformer itself doesn't go through the step of turning AC (whose voltage has already been lowered) to DC, some other component will before it (the electricty) hits the battery to be charged.