MAXOAK Laptop Power Bank 185Wh/50000mAh(Max.130W) Portable Laptop Charger External Battery Pack for Laptop iPad Phone Notebook

You need to look no further for a reliable 5 STARS power bank.I own a 17” ASUS G750-JM with an intel i7 quad core and Geforce 860m GTX. In terms of electricity consumption, my laptop is definitely power hungry. I have all 4 ram slots full and 2 hard drives installed.Before purchasing the K2 power bank I had purchased another power bank but had to return it because it could not power my laptop, not even when off.With the K2 I was able to get almost 9 hours of power on standby only. Screen saver was off to prevent the screen from turning off. Yes, the power bank kept my huge laptop on for almost 9 hours on standby (not using the computer). This test was performed to figure out how long the laptop could be powered by the K2.I got 6 hours of power under normal laptop usage, I was even able to watch a dvd movie for about 2 hours and still had more than half the power left to do some work and mess around. I should mention that I had an external mouse and keyboard plugged in the USB slots during both tests, and even though the power consumption from these peripherals is minimal, it is something to keep in mind regarding the tests I ran, since in a real life scenario on an airplane for instance, the keyboard and the mouse will not be plugged in, therefore increasing the overall power left from the K2.Keep in mind that both tests were performed using the “high performance” power profile in windows 7. If I wanted to be more conservative, I could have lowered the screen brightness all the way down, turn off the laptop’s keyboard backlight, and put the power profile on “power saver” which overall could have given me a few more hours of juice in both tests, but since I almost never use the power saver windows profile, I thought I would use it under more realistic circumstances that apply to me on a daily basis. The K2 performed fantastic!Things you need to know and consider: The battery will not change my laptop when I am using it. That is because my laptop is a power hungry one (this will probably not apply to your laptop). I have no problem with that because honestly all I want is to be able to use it on the go. So if you own a power hungry laptop like mine, make sure your laptop’s battery is charged all the way before using it, so that the K2 will hold the charge at 100% for 6 or more hours until the K2 discharges completely, then when that happens you can continue to use your laptop’s battery for as long that one will last. If your laptop is a power hungry one and you wanted your laptop’s battery to be charged by the K2, you can do so if you turn off the laptop. In that case the K2 will be able to recharge the battery of your laptop. So, charging the laptop’s battery is an issue only if the laptop is on, but if you do not have a power hungry laptop like mine, you will sure be able to use your laptop while simultaneously charging its battery if it was discharged.This honestly does not bother me because like I said, what matters to me is being able to use my power hungry laptop on the go, which so far other power banks simply have not been able to do.I’ve read the reviews for power banks of other brands out there and they all scared me honestly. I read the reviews for the K2 and I was convinced I could try it with confidence, and boy… I am glad I trusted them!This is exactly what I was looking for. I am really looking forward to trying the K2 during my next international flight and probably being the only one in the plane with the laptop on during the entire flight.All USB ports worked fine. The unit looks really high quality. It’s a bit on the heavier side but listen: we are talking about quality here not something made out of cheap plastic, the unit looks and feels very durable. It can be fully charged over 1000 times. That’s a lot of times… to give you an idea, there are 365 days in a year. Are you going to be using the K2 every day? Very likely not! And if you would, you could do it for about 3 years. That’s a lot of time. Batteries degrade over time whether you use them or not, so more realistically this unit will last me 5 years maybe more, which is plenty of time for me. The original battery from an iphone 3GS lasted me 6 years (it recently died), and that was because I gave it good maintenance. If you plan on having the battery of your devices or power banks last as long as they possibly can, I recommend you to inform yourself about the type of battery your electronic device is using and learn the best practices to maintain the quality and extend the life of your battery. All the batteries of the laptops I have used have lasted me very long because I always gave them great maintenance.I found on youtube what seems to be an official video of the K2, check it out: [...]The customer support for the K2 is among the best I’ve ever ran into. The unit came with a free gift which was another smaller power bank for smartphones and tablet. I thought that was nice. It turned out the small power bank was defective and so I corresponded through amazon with the K2’s customer support. Minutes later I received an email telling me that I was going to get a new small power bank (replacing the free gift) at no cost to me. The person I corresponded to was incredibly friendly and kind. Help was offered to me in case I had difficulties using the K2.Customer support so efficient is what unfortunately you almost NEVER run into on amazon. I can’t even mention the amount of times that sneaky amazon resellers have tried to scam the crap out of me, and have made almost impossible returns of cheap $2 purchases. Shame on them for being such beggars.This is not an issue you will run into with this company. You can buy with confidence.This product is a great purchase at this price. It’s a 50000mah power bank and you are not gonna find another one at this price. Read the reviews! Not only for the K2, but for the other power banks as well. Look for 1 star feedback on amazon and really ask yourself if you want to go through what other people have gone through with other brands. I don’t know about you, but I don’t like to waste my time and do trial and error or hope that I am the lucky one. I like to go with what works. If you are paying less, you are gonna get less. Before purchasing the K2 I thought I could save money buying another power bank, I did it and I wasted my time. After that I went back to the K2. I should have purchased it the first time, but oh well, another lesson learned…Thank you to the people at the MAXOAK for the very fast support given to me and for their kindness. It honestly took me longer to write my review than it took them to answer my inquiry, but I hope this review can help other customers not go through the hassle I experienced before buying the K2.

I conducted a thorough suite of tests on this portable battery and compared it against several other units sold by different vendors. The results are as follows and summarized below:The MaxOak unit concluded benchmarking on 16 August 2019 and in summary, was the only portable battery to pass every benchmark test consistently over 8 cycles, while surpassing the competitors’ units on 4 parameters, over 8 complete cycles.Charging: First test was conducted with an initial break-in charge/discharge loop cycle whereby unit was fully discharged, then fully charged in 4 cycles. The break in cycles were independent of the tests conducted below and necessary to provide accurate post break-in calibration results on the power meter, and performance metrics (all battery systems undergo this).Charging rate via the included adapter was connected to an ammeter, capacity tester, and current/voltage monitor with alarms set for any deviations outside acceptable ranges. Every charge cycle produced consistent results with respect to voltage, current, capacity, heat production, and time. This process was conducted 8 times in a temperature-controlled environment, and conclusively proved a solid charging system with consistent results. No deviations outside normal operation were detected, indicating the power supply is well built, as is the quality of the internal cells.Cells: Internal cells in this unit are different than traditional battery bank systems, which likely are what account for it's above average performance. For background, many power banks utilize 18650 cylindrical Lithium Ion cells, such as some laptop batteries. etc.This unit uses Lithium Polymer cells however, which allow for greater density, energy-to-space ratio, capacity, and consistent higher power delivery. The cells provided consistent discharge performance across all cycles, and at each voltage setting. The settings tested were:1) 20 Volt2) 12 Volt3) USB 5V @ 2.1 amps (2 ports included)4) USB 5V @ 1 amp (2 ports included)Each discharge produced the same results each time, showing the solid build quality of the cells utilized.Discharge tests: All USB ports tested identically and at their values stated with no voltage sag. This is generally consistent among most brands.The MaxOak however stands apart with the 12 volt and 20-volt settings. Unlike other battery systems tested, both the 12 volt and 20 volt discharge tests stayed true to their current ratings, consistently over all cycles. Each length of time was similar, and capacity meters proved this as well. It is worth noting that many competitors tested begin to show signs of wear on stress-tests after just a few discharge cycles.This is the only unit which remained consistent in all parameters across all cycles and continues to do so with zero signs of wear.On a final note, while stress-testing the battery to its maximum current draw, it's worth noting that the current draw from the load even exceeded the ratings stated, and were consistent as well. There was no overheating, no fuses blown, and is good to know if ever your load may need a boost of extra current draw.This is likely attributed to the battery technology used, and MaxOak certainly did not cut any corners with this.Complaints/Cons: None. This is the first unit I have ever tested which I can find no flaws in. Time will tell as to the longevity of this unit, and if anything changes, I will amend to this review. However, given the cycles I put this through while stress testing the battery over multiple cycles, it doesn't appear there will be any problems at this point going forward.The warranty will cover you if so.Bottom line: If you are thinking of buying a portable power supply- don't even think twice. Get the Max Oak- you will be happy you did! This company clearly knows what they are doing- and it reflects in the quality of at least this battery.I was not paid for any of my opinions/reviews above- I conducted this test as a hobbyist with expertise in the area and was impressed enough that I felt I should share a review for anyone considering the purchase of a portable power system.