Rethinking USB Charging: A Dive into the Chaos of Connectivity

This week, a reader expressed, “I have not faced this situation before, but I possess a Satechi external battery that I utilize to charge my Apple Watch (and other devices). It charges via USB-C.

“Last weekend, we stayed at a splendid hotel in Galveston, and charging my watch depleted about half of the battery. I attempted to recharge the battery using the same USB cable we use at home, but connected it to a USB port on a lamp. After 5-7 hours, it did not charge the battery. I also tested the Apple USB power brick we use at home with the same USB cable. After a few hours, it still did not charge.

“Upon returning home, I used the identical plug and USB cable in our standard outlets. Voila, when I checked it a couple of hours later, it was completely charged. So, can there be varying power levels among outlets in hotel rooms and the USB port on a lamp? I assumed it would be consistent.”

I can clarify one of your inquiries. The other one, not so much.

USB ports do not all supply equal power.

The USB standard initially specified that the ports deliver 5 volts with a maximum current of 0.5 amps.

This is meager compared to the demands of today’s power-hungry devices, but it sufficed to power keyboards, mice, and other peripherals.

Recent iterations of the USB standard have amplified the available power.

Currently, there are USB chargers that can provide up to 240 watts per port (48 volts at 5 amps).

Most contemporary devices can communicate with most modern USB chargers to negotiate a charging rate that satisfies both parties.

It’s worth noting that USB-C ports typically have greater power capacity than USB-A ports.

I would advise investing in a new USB-C charger that offers more power to replenish that battery. Look for the term USB with Power Delivery. Those chargers deliver increased power for quicker charging.

Cables can also influence charging speed. Examine the specifications when shopping for a charging cable, and you’ll usually find a maximum charging rate listed. Faster is superior.

As for why the Apple charger and your usual cable didn’t charge the battery – I lack an explanation for that.

I doubt the AC outlet was defective, but you never know.

I’d be curious to see if a different outlet would make it function, or if that Apple wall charger would work with another device.

Or perhaps that hotel room was simply jinxed. You can never be certain. – Tribune News Service