Best iPhone Battery Cases 2026: Mophie vs Newdery Compared (Slim vs High Capacity)

A battery case is a protective phone case with a built-in power pack, letting you recharge your device without carrying a separate charger.

Once popular, battery cases are now less common due to the rise of MagSafe and wireless power banks (see: Best magnetic power banks and MagSafe portable battery packs for iPhone). The choice between the two comes down to convenience versus capacity: battery cases offer an all-in-one solution, while magnetic power banks provide more flexibility and higher charge.

Battery cases are ideal if you want a simple, “always there” power source. Because the battery is built in, you don’t need to remember extra cables or accessories – and you get added drop protection at the same time.

They’re especially useful for:

• Forgetful travelers who don’t want to carry separate chargers
• Users needing protection alongside extra battery
• Active professionals who want a secure, wired connection
• Minimalists who prefer one device instead of two

The downsides are added bulk and limited longevity, as cases are tied to specific phone models. They also tend to have smaller batteries (around 3000mAh) compared to the 5000mAh+ typical of standalone power banks.

Still, their key advantage is convenience: reliable backup power, always attached to your phone.

So you can find the best battery case for your iPhone, this article looks at options from our two favorite battery case manufacturers: Mophie and Newdery. There are options for all iPhones from the past few years, because, frankly, it’s the older iPhones that tend to need the battery boost. You may also want to check out our roundup reviews of the best iPhone 15 cases, best iPhone 16 cases and best iPhone 17 cases.

Does Apple make a battery case for iPhone?

Battery cases for iPhones used to be all the rage. Apple even made one from 2015 to 2019—the Apple Smart Battery Case that was mocked for its humped back, which was last seen for iPhone 11. Apple then switched to a magnetic power bank (the Apple MagSafe Battery Pack), and even got bored with that until it released a new one for the iPhone Air. There are much better magnetic alternatives—see our reviews of the best magnetic power banks for iPhone.

Which battery case is best: Mophie vs Newdery

Choosing between Mophie and Newdery battery cases depends on whether you prioritize a slim, premium design or maximum charging capacity at an affordable price. While Mophie has long been the market leader for iPhone battery cases, Newdery has established itself as a reliable alternative that often provides significantly more power for a lower cost.

Mophie Juice Pack Series
Mophie’s Juice Pack is generally considered the “best” for users who want a high-quality, integrated feel without excessive bulk. The latest models for the iPhone 17 Pro and 17 Pro Max continue this trend by being slimmer and lighter than previous iterations.

• Design and Build: Mophie uses a signature two-piece design where the top pulls off to allow the phone to slide onto a built-in USB-C connector. In our review of the Mophie Juice Pack for iPhone 17 Pro, we note that “Mophie keeps making its Juice Pack battery cases slimmer, lighter and more robust than previous models”.
• Performance: Because the cases are slim, the batteries are smaller (typically 2,400mAh to 3,600mAh). In tests, these cases usually provide a 50% to 55% recharge, which is intended to get a user through the day rather than providing multiple full charges.
• Protection: Mophie cases offer 6-foot drop protection and include raised corners to save the screen from impacts.

Newdery Battery Case Series
Newdery is the better choice for “power users” or travelers who need to stay away from a wall outlet for extended periods. They offer much higher capacities, including 5,000mAh and even 10,000mAh models.

• Design and Innovation: Unlike Mophie’s physical connector, some Newdery models for the iPhone 16 and 17 use internal wireless charging. As noted in our Newdery Battery Case for iPhone 16 review, “Newdery uses wireless charging so that there is no risk of jamming the phone into the case too hard and damaging the iPhone’s charging port.” . However, this makes the case significantly bulkier, often measuring nearly 2cm deep.
• Performance: The 5,000mAh Newdery case can recharge an iPhone 16 Pro to approximately 72%, compared to Mophie’s 50%. The 10,000mAh version can recharge a phone over 1.5 times.
• Value: Newdery cases are substantially cheaper, often priced around $30–$33, whereas Mophie cases typically retail for $99.95.

How battery cases work

Battery cases typically function through one of two primary connection methods:

• Physical Connector: Most traditional models, such as the Mophie Juice Pack, use a two-piece design where the phone slides into a base containing a built-in USB-C or Lightning connector. This physical link is generally more efficient than wireless alternatives.
• Internal Wireless Charging: Some modern cases, like those from Newdery, use internal wireless charging to power the phone while it is inside the case. This design eliminates the risk of damaging the phone’s charging port during installation.

Do battery cases damage your phone battery?

Battery cases are generally considered safe for your phone’s battery health, provided they are used correctly and come from reputable manufacturers. While they do not inherently “damage” the battery, they can introduce environmental factors – specifically heat – that may accelerate natural degradation over time.

What to avoid when using a battery case

To maintain your phone’s battery health while using a battery case, consider the following:

• Avoid “Parasite Loads”: Using your phone heavily (like watching video) while it is being charged by the case can create “mini-cycles” that deteriorate the battery faster.
• Monitor Charging Limits: Modern iPhones include features like “Optimized Battery Charging” or hard limits (such as stopping at 80%) to conserve battery longevity.
• Choose Trusted Brands: Experts recommend sticking to well-known brands like Mophie or tested alternatives like Newdery, as cheap, “no-name” hardware often lacks the protective circuits necessary to prevent overheating.

Do battery cases support fast charging?

Battery cases do support fast charging, though the implementation and speed vary significantly between models. Unlike standalone power banks, which often rely on magnetic wireless connections, battery cases typically use a physical connector – such as USB-C – to deliver power more efficiently.

The fastest way to charge an iPhone remains a wired connection. Many modern battery cases utilize an integrated USB-C connector that plugs directly into the phone’s port. Others have designed cases that charge the phone wirelessly while it sits inside the case. While this reduces the risk of damaging the phone’s charging port, it results in slower charging speeds compared to a direct “hard” connection.

Would a MagSafe Power Bank be better?

While battery cases offer protection, they are often “bulkier than a normal case” and rarely offer a full 100% recharge. For example, the Mophie Juice Pack for iPhone 17 Pro typically recharges a drained device to about 55%.

In contrast, as noted in Best magnetic power banks and MagSafe portable battery packs for iPhone, a 10K (10,000mAh) power bank can charge a phone close to two times over. You should choose a power bank if you prioritize maximum battery life for long-haul travel or camping, or if you want to keep your phone slim most of the time and only add bulk when a charge is actually needed.