ROMOSSPower Bank, 40,000mAh 65W Portable Laptop Charger with USB C Fast Charging, External Battery Pack Compatible with MacBook Pro/Air, Dell XPS, iPad, iPhone 15, Samsung, Tablet, Steam Deck

I purchased this right in the spring of 2020 and it’s still going strong! It’s literally charging my iPhone right now via usb- C.UPDATE 12/22/2022: I got another one!Amazon won't let me make two reviews, so I am updating my original review. I first purchased this battery bank on 03/09/2020 and now, nearly three years later, I saw that this was on a 40% off sale, so I HAD to jump on that. This battery has been dependable, reliable, consistent, steady, stable, trustworthy, steadfast, unwavering, and...... reliable haha.You can see two years of wear and tear between the two in my attached photos, and I am extremely pleased with this brand and the quality of this battery. I don't even charge my phone from the wall anymore. I just charge this battery and charge my phone from it. Having two now will make that very useful. Just one of these is enough to charge my iPhone 13 Pro Max 9 full times from dead with a little bit of power left, as my phone has a 4,352mAh battery. With the fast charging, I couldn't imagine needing a different one. The 60,000mAh ROMOSS model was very enticing, but this was 40% off so this one is the winner.I'm not at all affiliated with the seller or brand, I just want to share my surprisingly excellent experience with you all. This is the battery bank to have if you want some charging insurance through power outages or if you, like me, like to play full controller games on your phone (it's call of duty mobile for me) for hours and hour and hours on end and need a portable, convenient power bank. These guys charge at a rate of 18w (9v 2A) via usb C and at 10W via micro-USB. I always opt for fast charging, as a battery of this capacity takes quite a while to charge. It takes a solid 8-9 hours to fast charge these from dead to full, and around 13-14 hours if you don't have a USB C charger. They take days of use before they die, though. Now that I have two, that's a problem of the past. Just recently, my IMUTO 30,000mAh power bank stopped charging through its only input, so I'm glad to have found this one on a sale! I paid full price the first time around and I would have done it again too.Anyways, 10/10. Absolutely recommend. I've never had any issues whatsoever with mine in nearly three years. All of the ports still work, the capacity is undoubtedly lower because batteries aren't immortal, but it still keeps a very solid charge after hundreds of charge and discharge cycles. I can still charge my phone and Apple Watch around 8 times each, maybe a little bit less. So don't worry about whether or not it will continue to work for you!I will update this review again if ever necessary.

I bought this to power my Meta Quest 3 VR headset. I've been wanting something that truly allowed my headset to draw 18 Watts. This battery does just that! After a two-hour session on Automobilista 2 (racing sim), My headset battery went from 100% to 98%, and the ROMOSS 40000mwh battery went from 100% to 85%. Are there cons? Well, it's heavy, but what do you expect for 40000mwh battery? The charger it comes with charges fine, but seems slow. This isn't a show stopper, because you can charge overnight, and use it practically all day. If it can handle a VR headset this well, I am sure it can handle pretty much any device you want to supply battery power. Cables are important. Do your research! I am using the Fasgear USB C to USB C Cable 10ft Right Angle 90 Degree 100W 5A PD.

This is a very sturdy charger and works for my cell phone, tablet, Kindle, and Chromebook.It is simple to use and lasts for about 3 weeks when fully charged.I highly recommend this charger!!!

This unit takes forever to charge (12 hours plus from a zero state) when using a standard usb connection. I haven't had the opportunity to use a USB-C connector with more amperage, but still guessing something around 6-8 hours might be required. The first charge only showed 99%, no matter how long it sat charging. I used the 99% on a small fan we run in a cabin to circulate air. Ran the fan about 32 hours before it hit zero. That's about 4x the smaller standard battery chargers I have around the house. It is heavy, so not great for travelling, but if you need a big charge, it may be worth it. Second charge on this unit showed 100%.Just a heads-up....this seems to stay on 100 or 99% for about half the battery life, then decreases somewhat rapidly from there. May just be my charger, but it's hard to know how much charge you have once you start to use a full charge.

The build quality feels nice. The usability is easy to understand. Charges my zfold 3 easily with the super fast charging from the USB C port. The unit charges quickly as well. I have a portable USB C screen that I have for on the go and it also easily powers it. The USB c power delivery is really nice. It's a literal brick on weight though, but well worth it from the amount of juice it has. Design is also simple, nothing fancy and fits in my backpack with ease.

This can easily charge my iPhone pro max maybe 8 times before needing to be recharged. It charges fast and the lcd display adds a nice touch. There are a lot of ports on this and it’s shaped like a small brick. Not sure how durable it is if dropped. Wish it came with a protective carry bag or something to protect it.

I purchased this charger and noticed it would occasionally ‘reset’ when plugging in a device to charge. It would flash all segments of the display and then read 0% and not provide any current. Plugging the charger into a power source would return percentage charge back to where it was before the reset. The device would then function normally. This happened approximately 4 times in the first 3 months of use.I contacted Romoss and they promptly sent me a replacement. So far the replacement unit has functioned without a problem.To thank them for the replacement I decided to measure the capacity of the powerbank and post it with this review.I drained the power back to 0% then charged it fully. I then discharged it fully using a resistive load bank.At 5 volts and a constant current of 2.0 amps the powerbank provided 27.9 AH or 141.6 WH. That is 94% of its rated 40AH capacity.I recharged the powerbank and measured the capacity by recharging my phone over the span of 11 days.again at 5 volts, the powerbank provided 26.3 AH and 133.6 WH. That is 89% of its rated capacity, not bad considering 11 days of self discharge added in.Thank you Romoss for a powerbank with an honest 40,000 mAh ranting. Thank you for the replacement.