Why do you need a battery case for your Galaxy Note 9? The phone already has fantastic battery life, but sometimes things happen. Maybe you're going on a weekend camping trip without power, or maybe you just forgot to charge your phone overnight and have to rush out to work. It's also an older phone so maybe the battery isn't what it used to be. Whatever the reason, a battery case is always handy to have. It adds significant thickness to the already huge Note 9, but that's better for some than having a dead phone in your pocket.
Mophie is one of the most recognizable brands when it comes to batteries and charging accessories, and its popular Juice Pack is available for the Galaxy Note 9. Its capacity is fairly small at 2,525mAh, but the Juice Pack supports wireless charging for easy top-ups, just like the Note 9 itself, and the speaker grills on the bottom reroute your audio to come from the front of the phone.
The Slim Power case provides the Note 9 with an additional 5000mAh and features a "chinless" design that keeps the height of the phone to a minimum. It charges over USB-C and even supports passthrough charging, meaning the phone will charge before the case when plugged in. The Slim Power case is a great option to have around in case of long, power-intensive days.
It might cost a pretty penny, but the NEWDERY Galaxy Note 9 battery case offers a 10,000 mAh battery while being compatible with Qi wireless charging. That basically provides 200% extra battery life and makes it that much easier to keep the battery full.
Noticing a trend? A lot of these battery cases feature the exact same design, likely being made by the same manufacturer. Just like the ZeroLemon Slim Power, Punkcase offers 5000mAh with a lifetime warranty and passthrough charging over USB-C. The power button lets you turn off the case when you want to run off of the Note 9's internal battery, and you can check your charge level using the four LED indicators on the back.
If you need the absolute highest capacity battery possible, along with a healthy amount of shock protection, and don't care whatsoever about the size of your phone, ZeroLemon's ZeroShock case is worth a look. It packs an insane 10,000mAh, meaning your Note 9 could last through an entire weekend with ease, and it even comes with a belt clip — because let's be honest, there's no way this is going to fit in your pocket.
The i-BLADES Smartcase is a thin polycarbonate case that uses magnets to attach a separate 1800mAh battery pack. In addition, it houses additional storage for your phone, along with an extra microSD slot. With a much smaller battery compared to the alternatives, it's hard to recommend the i-BLADES case at its high price, but it's a unique and extremely slim option that provides just a bit of extra juice for when you're in a pinch.
Turn your Note 9 into a weekend warrior
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Whether you're going on a weekend camping trip or you're traveling and don't want to rely on undependable airplane power outlets, there are plenty of reasons you might want to stretch the battery life of the Note 9 even further than it already gets on its own. Just about any of these battery cases will help extend your Note 9's longevity, but Mophie is both the most recognizable brand and the maker of the most convenient Note 9 case; being able to drop your phone or battery case on a wireless charger at night is priceless.
If, however, you need something more specialized, many of the other battery cases listed above provide twice the battery capacity, and the ZeroLemon ZeroShock quadruples it — albeit with the trade-off of a dramatically thicker form factor. If you're looking for something truly interesting, the i-Blades Smartcase has the smallest battery capacity but the most flexibility; you can add additional storage or even larger battery cells.
If you're looking to deck out your phone even more, then you might want to check out some great accessories to go along with it.
