Does it have the center pin, so it can be used to charge the battery, and not merely to power the laptop?

Question

Accepted Answer

Yes. The connector in the photo is a 7.4 mm × 5.0 mm DC male plug with a center pin.

Can it charge a battery?
Not directly. This is only a cable/connector, not a charger. To charge a battery safely, you need a proper charging circuit/module that controls constant current (CC) and constant voltage (CV) and stops at the correct cutoff voltage.

The center pin on this type of plug is usually for communication/identification (common on Dell/HP laptop power adapters), not for battery charging. If you connect a battery directly to a 19V/19.5V adapter through this cable, you may overcharge or overcurrent the battery, damage it, or cause fire/explosion.

If you want to use it to charge a battery:

· Use a compatible lithium battery charger module.
· Connect the adapter output to the charger module input.
· Connect the battery to the charger module battery terminals.
· Leave the center pin unused unless you know the exact circuit.
· Check voltage and polarity with a multimeter before connecting.
· Never charge unattended.

Example: a 7.4V Li-ion battery charges to 8.4V, so a 19V adapter cannot be connected directly.

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