Safe/healthy to use 15W USB-C charger with base M1 Pro MBP 14?

[bootz]

I have a bunch of old Google WiFi 5V 3A 15W USB-C chargers. I usually charge my MBP overnight at home with the included MagSafe 3 charger, but I spend 5-6 hours a day in a remote location. Usually I make it back with plenty of battery to spare. Is it healthy or harmful to use a low power AC adapter with the new MBPs? When I first plugged it in, it said "Not charging". A few minutes later, it changed to charging. At 79%, macOS estimates 100% in a little over 5 hours.

Is this trickle charging good for the computer? What about when just enough power is provided to run the computer but not charge the battery? What happens if the USB-C PD is 15W but the computer needs two or three times the amount?

 

[russell_314]

I'm no expert but I wouldn't think it would be harmful if the computer was off or sleeping. Perhaps if you were using it there would be extra wear on the battery because it's having to run off battery. I would be careful that all those old chargers are safe. Sometimes a cheap charger can be dangerous and put mains voltage down the USB line.

A better question would be why? I can see in a pinch if you forgot your charger but the cost savings for a 2k+ laptop doesn't really make sense.

Maybe someone with more knowledge of the circuitry could give better advice.

 

[bootz]

I'm no expert but I wouldn't think it would be harmful if the computer was off or sleeping. Perhaps if you were using it there would be extra wear on the battery because it's having to run off battery. I would be careful that all those old chargers are safe. Sometimes a cheap charger can be dangerous and put mains voltage down the USB line.

A better question would be why? I can see in a pinch if you forgot your charger but the cost savings for a 2k+ laptop doesn't really make sense.

Maybe someone with more knowledge of the circuitry could give better advice.

Google GL0102 charger

As to why? Because I can haha. I did read that slow charging and keeping the charge in the 10-85% range is best for battery life. I only use the HDMI port at this time. Haven't had a need to use any of my old USB 3.x devices yet, but I was thinking of getting a small hub with USB-C PD.