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The phone dies at dusk on a campsite, the map is gone, and the only outlet for miles is the brick in a jacket pocket. The question is how does portable charger work, and the short answer is that it stores energy in a battery and hands it back through its ports when a device is plugged in. This guide follows that energy from the wall outlet into the pack and back out to a phone, a laptop, or a small fan.
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How does portable charger work?
A portable charger is a battery with ports and a manager in between. Plug it into a wall outlet, a solar panel, or a car outlet and it stores energy in its lithium-ion battery; plug a device into one of its ports and the pack hands that energy back. The GENSROCK listing shows the shape of it: a 24,000mAh pack with 88Wh of stored energy, 8 output ports, and a 150W peak AC outlet. The Ridge listing shows the travel size: a 10,000mAh pack with 20W charging and built-in cables. Between the battery and the ports sits a battery management system, or BMS, which watches charge, discharge and heat and cuts off the flow when limits are passed.
Step 1: Charge the pack first
A portable charger has to be charged before it can charge anything else. The GENSROCK listing states three recharging modes: an AC outlet, a solar panel, or a car outlet, and the pack can be used while charging. The solar panel is not included with that pack, so it is a separate piece of gear. A digital screen on the pack displays real-time energy levels and status, so the charge level is visible before the pack leaves the house. The Ridge listing states built-in cables and an LED charge status indicator that displays battery and charge levels at a glance. Charge the pack fully before a trip, and check the screen or the indicator before leaving.
Step 2: The battery stores the energy
Capacity is the size of the tank, and the listings state it in milliamp-hours and watt-hours. The GENSROCK pack lists 24,000mAh and 88Wh, while the Ridge pack lists 10,000mAh. The Ridge listing states up to three full phone charges from its 10,000mAh, which shows how capacity turns into charges. Cycle life is the count of full charge and discharge rounds the pack survives: the GENSROCK listing states cycle life over 1500 times, with a 2 Year Manufacturer warranty and 24 months of support behind it. At 2.3 pounds, the GENSROCK pack is built to carry, and its 2 lighting modes, always on and SOS, cover campsite and outage use. A bigger capacity number means more charges before the pack itself needs charging, so compare the milliamp-hour figure before the watt-hour figure.
Step 3: The ports hand the power back
Ports decide what the pack can run and how fast it charges. The GENSROCK listing states 8 output ports and 5 output methods: 2 AC outlets at 120W with a 150W peak, 2 12V DC ports, 1 Type-C port, 2 QC 3.0 ports, and 1 5V/2.4A USB port. The listing states the pack powers devices under 150W, including phones, tablets, laptops, drones, headphones, cameras, a radio, a USB night light and a mini fan. The Ridge listing states up to 15W wireless charging on its magnetic pad and a 2.5W rate for a smartwatch, with built-in Lightning and USB-C cables. Match the port to the device: an AC outlet for a laptop, a Type-C or QC 3.0 port for a phone or tablet, and the wireless pad for a phone that supports it.
| Output | Stated figure | What it powers |
|---|---|---|
| AC outlets | 2 at 120W, 150W peak | Laptops and devices under 150W |
| Type-C and QC 3.0 USB | 1 Type-C port, 2 QC 3.0 ports | Phones and tablets |
| 12V DC ports | 2 ports | 12V gear |
| Wireless pad | Up to 15W, 2.5W for a watch | Phones and smartwatches |
Check the port figures before plugging in a laptop, since the AC outlets carry the highest wattage on the GENSROCK pack.
Ways to make a portable charger last longer
- Charge in an open, well-ventilated space rather than a closed bag or pocket, as the Ridge listing states.
- If the pack and the device both feel warm, allow 10-15 minutes for them to cool before charging again.
- Use the port that fits the device: an AC outlet for a laptop, a Type-C or QC 3.0 port for a phone.
- Watch the screen or the LED indicator so the pack is charged before a trip.
- Keep the pack charged between trips so it is ready when the power goes out.
FAQ: power away from the grid
How long does a portable charger take to charge?
The listings here state no charge time, so there is no figure to quote. The GENSROCK listing states three recharging modes, AC outlet, solar panel, or car outlet, and the pack can be used while charging. The charge time depends on the power source and the size of the pack, so check the screen or the indicator while it charges.
Can a portable charger charge a laptop?
Yes, if the ports and wattage fit. The GENSROCK listing states 2 AC outlets at 120W with a 150W peak and lists laptops among the devices it powers under 150W. Check that the laptop draws less than the outlet can give, and use the AC outlet rather than a USB port for a laptop. See the best portable power banks for laptop charging for packs built for that job.
How many times can a portable charger charge a phone?
It depends on the capacity of the pack and the phone. The Ridge listing states up to three full phone charges from 10,000mAh. A larger pack such as the GENSROCK at 24,000mAh holds more charges, so compare the milliamp-hour figure when choosing.
Can I use a portable charger while it charges?
Yes, on the GENSROCK listing, which states the pack can be used while charging. The pack charges from an AC outlet, a solar panel, or a car outlet, so it can take in power and give it out at the same time.
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