Is it dangerous to use a higher-amperage laptop AC adapter?

I have two laptop AC adapters rated for 19V. One supplies 1.6A and the other 4A. Would I damage my laptop/battery if I use the larger adapter in a laptop designed for the smaller one?

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canucksgirl4 years ago
As far as I know, the voltage must be the same, but a higher amperage will not cause problems. If the laptop needs 1.6 amps but your using a 4 amp adapter, the laptop should only draw 1.6 amps (again, that's for amps, the voltage must be the same, which you said it is).
aneeshj21 year ago

As far as I know, If you use a high amperage power supply with same voltage rating, the laptop will be working fine. But there can be problems with your laptop battery life. Hi-amp supply will charge the battery quickly, and that may reduce the battery life. The effect of quick charging depends on the battery type.

tkennedy104 years ago
No, it is safe to use the high amperage. But when you select the correct laptop charger, please have a look at the following useful methods:
1) Output Voltage is within +/- 5% of your old charger's output.
For example, if your old charger provides 19.5V, then you can use a charger that provides 20.5V or 18.5V.

2) Output Current is the same or higher than that of your old charger.
For example, if your original adapter provides 3.42 Amps, then you can use a charger that provides 3.42 Amps, 3.9 Amps or higher.

3)Connector tip must fit securely into your laptop.

Use your laptop model and part number of your original charger to search the compatible adapter:
kingsqueak4 years ago
Voltage must match.

Polarity of the connector must match (critical though most are center positive).

Output mode must match
It MUST be an output of DC or AC to match the device, beware adapters that output the less than usual AC voltages (Computer speaker supplies seem to be 12V AC as an example). In general it should be a DC output type for a laptop, check that.

The amperage output rating must be equal to or greater than what is recommended. If it is lower you will burn out the supply or the device.