Can I use 100w charger for 65w Laptop? (Answer, Pros & Cons)

Laptops have a considerably big battery capacity. When they are charged with an adapter with a low power rating, it may take hours to attain 100% charge. This can be frustrating and lowers the sophistication of the laptop. So, it is important to charge them with adapters that provide a higher power rating. But how much high?

Most of the laptops released now have adopted the type C port for charging and this has enabled them to provide fast charging support too. Laptops can now charge at 65W power which completes the charging within one or two hours.

The adapter provided with the laptop will be of the same power rating. But what if you use a higher-rating adapter to charge the device? Does it damage the laptop battery? Let us discuss these aspects in detail.

Can I use 100w charger for 65w Laptop

Can I use 100w charger for 65w Laptop?

There are no issues in using a 100-Watt charger for a 65 watts laptop if the rated voltage and polarity is the same as of the adapter provided with the device. Because the device is designed to draw a maximum of 65 watts of power even if the adapter can provide 100 watts.

The power rating mentioned in the charging adapter is only the maximum output it can provide. But the device is designed to draw only the rated amount of power which will never damage the device at any point.

We shall understand why it doesn’t affect the device by knowing the working principle of the charging adapter and its relation with the device battery while charging.

Working Principle of Charging Unit

Laptops use Lithium-ion battery which like every other battery tech has two electrodes and an electrolyte. It has a positive electrode and a negative electrode which are separated by an electrolyte. 

When the battery is put on charge using a charging adapter, electrons from the positive electrode move towards the negative electrode but reach the negative electrode through the device in a longer path. 

The reaction deposits lithium ions on the negative electrode. When the negative terminal is full of lithium ions, the charging adapter will cut off the power automatically. 

Similarly, when the device is using battery power, the ions will move from the negative to the positive electrode, which gives a current that powers the device. 

When the device fully uses the battery backup, it will automatically shut down and requires recharging of the battery for the device to work.

Lithium-ion batteries are compact and are widely used in tech gadgets. They are smaller in size and can withstand several charging cycles. It can also be used for fast charging and wireless charging. Due to such advantages, it is used in all the tech gadgets like smartphones and laptops. 

Read: Is 5 Hours of Battery Life Good for a Laptop?

How does the battery and charging adapters work together?

The devices are designed in such a way that when the battery discharges too much and becomes dead, the device automatically shuts down. Also, when the charging is full and excess voltage is passing through the battery, the charging adapter will cut off its supply. This is how all the battery charging adapters work with the gadgets without damaging the device. 

So, even if you use a 100W charging brick with a 65W battery device, it will only take up the 65W power from the brick. There are also chances for faster charging with a 100W brick but, your device must support the fast-charging tech. 

Fast charging also depends on the device because you can find the batteries to be in several small compartments and each compartment is simultaneously charged instead of a single pack. So, this setup is required for getting a super-fast charging process and it can only be provided with the design of the device battery. 

If you see the charging cycle of the battery, the first 50% will be faster and this produces some amount of heat. But as the charging proceeds further, the rate of charging will slow down, and eventually when it reaches 90%, trickle charging occurs. This is to safeguard the life of the battery and provide a longer charging cycle. 

When such technology is incorporated into charging the battery, there are very less chances of battery damage or device issues. Therefore, it is absolutely safe to use a 100W charging brick with a 65W device if it has the same voltage rating and enjoys fast charging if the device supports it. 

Read: List of Latest 17 inch Laptop for Business Travel

Pros and Cons of using 100w charger for 65w Laptop

Every method can have some kind of pros and cons which we shall discuss here for this condition:


  • Fast charging of the device is possible when you use a higher power-rated charging adapter. You can simply charge the device within an hour and use it comfortably.
  • You can use a single charger for multiple devices provided it has the same interface. For example, if your charging brick has a USB-C pin, then you can use it for multiple devices that use the same USB-C port for charging. 


  • The higher wattage of the charging adapter is not an issue, but if you are using an adapter with a different voltage rating, the adapter may burn.
    For example: if your device comes with an adapter with a power rating of 65W and a voltage rating of 20V, then you must use a 100W charger with the same 20V rating. Otherwise, the excess or deficient voltage will damage the adapter and the device
  • Also, you need to make sure of the polarity of the charging bricks to ensure the safety of the device.
  • If you are unaware of both the voltage rating and polarity, it is risky to use the charging bricks which can lead to the burning of the device battery while charging. 

These are the pros and cons associated with using a higher-watt charging brick for a lower-watt battery device. 

Read: List of Best Laptops for Work at Home


With the help of this guide, you might be able to use a 100W charging brick for your laptop without any issues. But make sure that they have the same voltage and polarity as your default adapter that comes with your device.

In any situation, it is always safe to use the adapter that comes with the device and it will ensure safe charging in any situation. 

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