An efficient charging case with an elegant design

Something I have disliked about charging cases since I first started using them many years ago is the Micro USB connection that they all needed to be powered by. Even now, some of the big name brands continue to make charging cases that use Micro USB to power the case up. This is a nuisance since my iPhone uses Lightning and my MacBook Pro uses USB-C I don’t want to drag a third cable along. In fact, aside from my iPhone and iPad, most of my devices now use USB-C for charging, so finding a charging case that I could power up with one of the two cables I keep with me was tough. That’s what I thought until ZeroLemon introduced me to their new charging case with a 4000mAh battery.


The iPhone X 4000mAh Battery Case also known as the ZeroLemon Slim Juicer Battery Case can extend 100% power to the iPhone X since it’s internal battery is 3,500 mAh. The Slim Juicer provides protection for the iPhone to keep it free of scratches and other daily wear and tear. The inside of the case has an Apple-certified Lightning connector and the exterior port is USB-C. There are 4 LED lights that indicate the battery level of the case and charging status. The ZeroLemon package contains the Slim Juicer, USB-A to USB-C charging cable, and a ZeroLemon Zero Defect Card. Even though it provides minor protection for the iPhone, the Slim Juicer is not designed to offer any screen protection.

ZeroLemon iPhone X Battery Case REVIEW

One thing I want to point out here is that this particular model (Y1341) does not support wireless charging. When you visit the product’s page on, there is a note called out — Please note wireless charging is NOT supported by this battery case. I want to make sure this is noted here because there is another ZeroLemon case sold on (US) that does support wireless charging. That case’s model number is Y1356 and the detail is called out as follows — Qi wireless charging technology: wireless charging Supported. No longer need to take off the battery case when using the wireless charger to charge your iPhone x together with the battery case. Unfortunately, I could not take advantage of the wireless support, but it didn’t stop me from enjoying the case. 


  • Battery Input: 5V/1.3A (Max)
  • Battery Output: 5V/1.3A
  • Case Dimension: 6.45 x 2.95 x 0.74 inches (L x W x H)
  • Product Weight: 4.4 Oz


Even though ZeroLemon designed a very nice looking charging case, they provided it to me in a white bag with their logo on it and some text on the back about the 100% ZeroLemon Promise. There was nothing at all on the bag or on the box inside about the product. Inside the small white box, I did find the battery case, USB-C cable, and a few small cards. One was the manual, the other two were just asking for you to check them out on Amazon and social media. It was some of the poorest excuses I have found for product packaging. I don’t like excessive packaging, but something more than this plastic bag would be a nice step up for this case.

ZeroLemon iPhone X Battery Case REVIEW

Installing the phone into the case is actually quite easy. Some charging cases can make this a difficult process, but ZeroLemon did a really nice job with the design of the case and they made an effort to keep it user-friendly. The top of the case comes off easily allowing me to slide my iPhone inside, it also snaps back on without any issues. I didn’t feel like the phone was going to come out of the case at all and that the two pieces of the case were secure when locked together. The buttons are made very well so when you press the volume up/down or power buttons, I feel like I’m just pressing the buttons directly on the phone. 

The Slim Juicer for the iPhone X supports pass-through charging, which means that when the case is connected to USB-C, it will charge the phone before it charges its internal battery. This is a very nice perk of charging cases and I’m glad it’s featured with the ZeroLemon. I didn’t detect any heat issues when the case was charging – either with the phone in it or without it. 

ZeroLemon iPhone X Battery Case REVIEW

Another great feature of the charging case is that there are directional speakers at the bottom that direct the sound outward. The iPhone X does have two separate stereo speakers on the phone – one at the bottom and one at the top near the front-facing camera.  Speakers being blocked by a large case was a big problem a few years ago, but now that the iPhone X has two sets of speakers, it’s not as a severe of an issue. I’m glad that ZeroLemon had the foresight to include this design feature so that I still have the same audio experience with or without the case. 

When I tested it, I looked at how well the case would recharge the phone autonomously from a charger. As it turns out, the iPhone X gained approximately 26% battery power in just over an hour’s time (67 minutes). That’s a 0.4% charge per minute. That rate is a little slower than I’ve found from recharging my iPhone X from a standard power bank. In another instance, I recharged my phone using a standard lightning cable and a 10050 mAh portable battery. In that test, I was averaging about 0.59% per minute. The difference does not bother me enough to not use the ZeroLemon case, but it’s worth noting that a recharge of the iPhone X might take a bit longer than you would expect from a different charging connection.

ZeroLemon iPhone X Battery Case REVIEW


The ZeroLemon Slim Juicer Battery Case for iPhone X was actually very impressive to me. The nicest thing about it was that I had emergency power for my iPhone when I needed it most (a lengthy trip to the hospital). It’s much more affordable than its competitors (around $40 at the time of publishing this article) and it features USB-C as it’s main method of power input. With the exception of its packaging, the ZeroLemon iPhone X Battery Case is a suitable companion for the iPhone X for those who need an extended battery.

For more details, visit ZeroLemon
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