Alpatronix Galaxy S9 Battery Case, BX440 4000mAh Slim Portable Protective Extended Charger Cover with Qi Wireless Charging Compatible for Samsung Galaxy S9 (5.8-inch) (Black) [Upgraded]

I have now had the product for a week and took notes while using it.It is a little heavy, but worth the extra weight for its usage.One day I let my phone battery run down to 59% at 1 pm and at the time had 4 bars for battery charge in the case. At 2 pm my phone was fully charged back up to 100% and it only used 1 bar as I still had 3 bars showing on the back of the case. Good Right! I have to warn you that the case does get quite warm when it is transferring its juice to your phone. But nothing that can't be tolerated.Other days went similar: 67% at 10:35a with 3 bars; turned on and reached 100% at 11:26a bars dropped down to 2.However, there were days with a glitch like these two:59% at 8:57 am with 2 bars on back; checked phone at 9:37 am and the phone was only charged up to 67% and the charge had kicked off and was no longer charging from case to phone. So I tried to turn the charging back on at 9:38 am with 1 bar left, but it would not turn the charger on with just the 1 bar and I had to use my cord by plugging it into the electrical outlet and the other end on my phone in order to charge from the 67% to the 100% plus get the case battery back up to 4 bars. From 9:39 am to 11:42 am the phone battery went to 100% but there was still 1 bar on case battery. At 2:09 pm phone still 100% and case went up to 2 bars. At 3:42 pm phone still 100% and case finally went to full 4 bar charge. So, in essence, it took 6 hours for the phone to charge back up to 100% and battery case to charge back up 100% to 4 bars, but with needing to plug in my charging cord.Another day at 12:30 am the phone was at 43% with 4 bars on case so turned it on to charge phone from the battery case. At 4:30 am it had kicked the case charge off with the phone only having 86% and the case having 3 bars. At 4:31 am turned case charger back on a with its 3 bars and at 7:25 am the phone was at 100% with the case having 1 bar, so I plugged in the phone to an outlet and at 10 am the phone was at 100% with the case having 4 full bars.It was disappointing that on some days the case charger was kicked off randomly. Not good if you are counting on getting a full charge. One does not always watch the pot boil (look at the phone constantly to make sure it is charging from the case to the phone). And if one is depending on a full charge and only ends up 67% or 86% or whatever percentage it decided to kick off at, one is going to get a rude awakening for whatever you had planned for that hopeful 100%.But overall, this battery charger is very convenient to have. Saves one from carrying around an electric cord charger and worrying if there is an outlet nearby.Great for things like going to a wedding and not wanting to run out of juice mid way. Or going on a trip and taking lots of pics and vids and not having to worry about the battery running down completely and missing those once in a lifetime pics.The case also seems to be very heavy duty for protection of a very expensive phone which is a bonus. As you are not only getting an extra battery for your phone, you are getting a great protective case for your phone.The price is not inexpensive, but not over-priced either. Definitely worth the cost for what it provides.I think Alpatronix may have a few bugs to still work out to make this battery charging case perfect, but as is, still a good investment and product that meets the consumers needs.

This is my 4th Alpatronix battery case. I have purchased one each time I upgrade my phone, and I bought one for my wife and daughter. They are great cases! My phone will almost be dead by the end of the work day, and the case provides rapid charging to completely recharge my phone with some charging still left over for later. The case is quite thick, but not really much more than a normal case would be. It has a solid feel with a smooth texture, but not slippery at all. I never worry about it slipping out of my hand. One of the things I love most is the fact that it is Qi computable for recharging. I don’t have to find a cord and I can just took it on my charging pad when I walk in the door. The case charges the phone first, and then the case, but it does rapid charge both of them. The only complaint I had before was the fact that the buttons on the side tended to break from spending all day in my pocket, but the case was still functional. When I received my new case today that problem has been fixed. The material that covers the buttons now has metal inside so no matter how many times I push the volume or power buttons they are not going to ever break off again. I’ve tried other battery cases and this one is superior to all of the others I have tried. I highly recommend it.Pros:Qi chargingMore that a full charge with power left overSmooth but textured no slip caseReinforced buttons that are sturdySolid protection for drops (I have dropped my phone multiple times and no damage to my phoneGreat customer service if you have any problemsCons: None

Poor quality product. First one came broken. Amazon replaced it for me. The second one lasted two months before the tab for the power button broke off, forcing me to jab my fingernail into the hole to turn off my screen. The built-in battery is decent and has functioned as intended, but gets incredibly hot while being discharged. The Qi charging is good, but does not support Quick charge either via Qi or wired. The case itself is very slippery and the buttons are so low profile that I had issues holding onto the phone. I was initially able to get the unit to work on the Qi charger with a Pop-socket, but after a couple weeks, it would start charging for about 10 seconds then stop, then start again continuously.

I would like to update my original review of this Alphtronix Galaxy S9 Battery case. The original one I received was not functioning properly. Their customer service promptly replaced the original case with a case that performs perfectly! Nice and light, and it charges both my phone and the case properly using the Qi wireless technology.I am very happy with my battery case and I will buy another one!

This battery pack is great. Easy to install on the phone, easy to get off (once you get the hang of it). It charges the phone quickly, and most importantly, without getting excessively hot. I could hold the phone and operate it without it being uncomfortable. But the best part is the wireless charging that allows you to charge it without plugging it in.

It's a good solid case and good back up battery

Great fit and light weight.Easy to fit and comfortable grip do not make your phone look like heavy brick.Plus extra power on the go. Charges faster then my other battery case.Easy to install.Great product for the money.

I ordered this for my wife but she has an S8 and this worked also. Only thing that she has a problem with is hard to turn up volume