In terms of convenience and functionality, rechargeable cases offer an advantage. They are designed to extend your iPhone battery life and provide great protection so whenever you're on-the-go, you won't have to carry a separate, and oftentimes heavyweight power bank or look for a nearby plug once your battery gets low.

On Amazon, you can find the best rechargeable cases for your iPhone. Here are five of them:

QTshine Battery Case for iPhone 6/6s/7/8

QTshine Battery Case is the number one best seller in cell phone battery charger cases. It is compatible with 4.7-inch iPhones such as iPhones 6, 6s, 7, and 8. Whether you're traveling, or camping, or going on a business trip or engaging in any outdoor occasions, you will never worry about your iPhone running out of battery because this case is equipped with a powerful 6000mAh built-in lithium polymer battery chip, more than double your iPhone's battery life.

This case has a 360-degree protective bumper design to protect your iPhone from scratches or other daily wear and tear. Certificated by CE, FC and RoHS, the case uses high-quality polymer batteries, safe circuit diagram design and internal chips to protect your smart phone from overheating, short-circuiting, over charging, and discharging.

Take note that this rechargeable case does not fit iPhone 6plus/6s plus/7plus/8plus (5.5 inch) and other larger, longer models. The brand advises users to use Apple airpods or other wireless Bluetooth headphone instead of iPhone lightning headphone or traditional 3.5mm headphones.

Swaller Battery Case for iPhone 6/6s

Extend 150 percent of your iPhone 6 or 6s' battery life equivalent to add 15 hours internet use, 16 hours video playback, 21 hours talking time, 75 hours audio playback, using this 4500mAh battery case.

This iPhone 6/6s charger case is made with soft material and hard-shell back plate. In order to protect your screen, a front bumper has been specially designed. It's also simple to use: Equipped with power level indicator LED lights, you just need press the button 3 seconds to start or stop charging. Its four LED battery level indicators let you know how much power you have: 25 percent, 50 percent, 75 percent or 100 percent.

Using this iPhone 6/6s charging case lets you charge and listen at same time when you use your original charging cable with its Sync-through technology. It is compatible with iPhone AirPods or any other wireless Bluetooth headphone accessories.

Swaller Battery Case for iPhone X/Xs/10

Is your iPhone model X or XS? This iPhone X/XS battery case provides 105% extra power with built-in 4100 mAh lithium ion battery, which is equivalent to 10 hours internet use, 10 hours video playback, 17 hours talking time, and 48 hours audio playback.

Compared to other rechargeable cases, Swaller iPhone X/Xs battery case has an ultra slim design made of Liquid Silicone Rubber, adding only 0. 24 inches to your iPhone X/Xs.

It also features a Sync-through technology so you can listen to your favorite music using your mobile device while charging.

PowerBear iPhone 5 / 5S / 5C / 5SE Battery Case

If you have an iPhone 5, 5S, 5C or 5SE, this rechargeable case is for you. This Amazon's Choice for "iPhone se charger case" boosts your battery power on the go by up to 250 percent. It also has a built-in USB charging port so you can charge another phone or device.

This charger is easy to use: Just press and hold the power button to charge your phone.

Battery Case for iPhone 11 Pro Max

Amazon's Choice for "iPhone 11 pro max battery case"

For iPhone Pro Max users, this battery case has more than 200 percent power at 7800mAh which offers you extra 18 hours talk time or 15 hours web browsing time, ensuring your iPhone will have the enough power during traveling or working outside.

To use, remove the top cover and slide the iPhone into the bottom of the battery case to start charging. Its fabulous sync-through technology can sync your iPhone 11 Pro Max to your laptop, Mac Book or PC without taking off the battery case.

This case's raised front lips and raised edges design prevents your iPhone and camera from scratches, while its hard-shell design protects your cellphone when dropping or falling. But take note that the case does not protect the phone screen.

For more rechargeable cases and other iPhone accessories, visit Amazon now!