The Nokia Lumia 820 is at the fag end of its life cycle, waiting to be succeeded by a more capable Lumia 825 or something, but it is still present in the hands of lots of people, who unanimously face the single most annoying issue on the 820, the disappointing battery life. I know I face it, because I have been using one for the past 7 months and I can tell you outright that the in-built 1650 mAh battery is bad, period.
Seeking respite from the incessant battery drains, my eyes grew wide when the well known Android “extended battery” maker, Mugen Power Batteries, announced that huge extended batteries for the Lumia 820 are in the works. There were two variants announced, and one of them was the 3600 mAh one with a special battery door. Needless to say, I got the biggest one. What follows is my experience with the accessory over a comfortably long term of 2 months to see if it is really worth it or not.
The Mugen Power 3600 mAh extended battery is made possible thanks to the removable battery cover on the phone. Since the extended battery is so huge, it comes along with a battery cover that fits with the Lumia 820. First, lets talk about the battery door for accommodating the huge battery.
The battery door was, at first, hard to fit. While the Lumia 820 did sit in it, it did not align with it properly and forget about snapping it on. But this was only with the first few attempts, in which the plastic doesn’t really conform with the device. Even if it is extremely hard to remove the battery door, once you remove and place it back a couple of times, it then slowly aligns and sits on the device nicely. Removing the cover takes an effort, but you can make it easier by pushing down on the camera unit and prying it open just like the original case.
Coming in at 16.5mm , the battery door surpasses the earlier 9.9mm with ease but it was surprisingly not that bulky, like I had expected. In all seriousness, this is bulky for a normal phone, but that is a given when you are purposely trading it off for a better battery. Even then, it feels nice in the hands, with curved edges making it unusually comfortable. There is a hole for the camera and the flash, and it doesn’t hinder its functions in any way. It rather protects the easily scratchable metal housing the camera is in, but since mine was already scratched, it only helped not scratching it further, if that’s even possible.
The battery door also has its own buttons on the sides. When it comes to build quality, the door, overall, looks well built with same matching colours as the Lumia 820 variants, in our case, red, but the buttons are of lower quality. While you can get past that fact easily, the tactility of those buttons is actually the problem.
The volume rocker and the camera button are shallow and do not reach the inner hardware buttons as well as the original case, but the power/lock button is worse. Having always used it for the primary action of opening the phone, it was frustrating for the initial few days. Yes, it did become useful later, much like the fitting.
The bottom, sides and top are not part of the bulk, because, that way it fits as a replaceable case rather than adding extra bulk to the original case. After using it for a month, we noticed that the door doesn’t take scratches that well, and was similar to the original in this aspect. We also noted some paint wearing off in the edges, which may be pronounced in a few months due to our rough handling of the device. But all aside, the extended battery is the star, so lets talk about that now.
The HLI-820XL 3.7V battery is rated at 3,600 mAh, a whopping 1950 mAh more than the in-built one. It is a Li-Ion unit and has a revealing stacked structure. It almost looks like there are two batteries in there. The battery sticks out of the phone, with battery door gladly covering it.
The Mugen Power Batteries’ package comes with some instructions and it is highly recommended that you follow them for an optimized performance. Refer the image below for the instructions –
As you can clearly see above, the first 4-5 cycles need to be treated carefully with about 8-12 hours on the charger, and it is recommended that the battery be charged even after it reaches 100%. We can attest to this, because, if otherwise, the battery drastically drains in 3 hours, so the first few cycles are crucial for the battery to reach optimal performance. For us, the first few cycles were more than 5, let say, about 10. For 10 days, we noticed a lot of irregularities in charging and discharging, with the battery levels highly inconsistent. But we were slowly getting better and better longevity with each cycle.
In terms of discharging, you need to note that the firmware on the Lumia 820 is not supposed to handle large capacity batteries and always shows the percentage wrongly. It does however notify us of a low battery when it is, but we have seen it last for more than a day under 20% which is just plain weird at times. So, one thing was clear, never trust the battery levels on the phone, and never forget to charge the battery before it goes to 0.
The battery performance after the initial days started getting better and better and there was no stopping it. Under extremely heavy usage, the original battery lasted 3-4 hours, but the 3600 mAh Mugen Power Battery with a very similar usage lasts more than ten hours. And if the usage is just normal, expect phenomenal battery life. It lasted upto two days at a stretch under normal stress, which was definitely not possible on the old battery. So, in terms of performance we are very satisfied with the accessory. It definitely delivers on its promise, and the major issue I had with the Lumia 820, which made it unusable as a daily driver is now solved, albeit with a few compromises.
In the end, the Mugen Power Batteries 3600 mAh extended battery for the Lumia 820 is definitely recommended if you are facing piss poor battery life and are ready to make compromises like bulk and weight. You can check out this accessory in the Mugen Power store, where it sells for about 89.50 USD with free shipping. It is available in Red, White, Yellow and Black colours.