Understanding Pass-Through Charging: How It Works And When To Use It

In today's tech-driven world, managing multiple devices and their charging needs can be cumbersome. Enter pass-through charging—a handy technology embedded in gadgets like power banks, docking stations, laptops, and some tablets. This feature enables users to charge multiple devices simultaneously from a single power source.

Pass-through charging is particularly beneficial when you're in a rush or lack access to multiple power outlets. While many power bank s equipped with this feature allow you to charge both the power bank and connected devices at once, some USB-C hubs may distribute power between their own operations and the connected peripherals.

How Does Pass-Through Charging Work?
Devices that support pass-through charging utilize power-regulating circuits to manage power distribution . For instance, in a power bank, these circuits might allocate all the power to a connected device or split it between the power bank and the device.

In the case of docking stations and USB-C hubs, pass-through charging relies on USB Power Delivery (PD) to supply power to connected devices. This only works if both the USB-C hub or docking station and the connected device support USB PD.

Additionally, most USB-C hubs that support pass-through charging have a maximum power limit they can transfer to a connected device. If a peripheral requires more power than the hub or docking station can provide, a direct power cable might be necessary.

Is Pass-Through Charging Worth It?
Pass-through charging has its advantages, but it also comes with drawbacks.

One of the primary downsides is slower charging times. Since the power is split between charging the power bank and the connected device, both will likely charge more slowly than if charged individually.

The technology is also less power-efficient compared to plugging a device directly into a charger. Many modern smartphones support charging speeds of around 67W, which may not be achievable through pass-through charging unless the power bank also supports such speeds.

Another concern is heat generation, particularly in power banks with Lithium-ion batteries. Pass-through charging can cause significant heat buildup, potentially leading to overheating and reducing the battery's lifespan. Therefore, it's best to use pass-through charging only when absolutely necessary.