MagicShine Improved 2011 MJ-828 4.4AH Li-ion Battery with LCD Capacity Display

Battery life is very long, even in very cold weather. I bought this as a replacement for a no-name battery. I can now run my 1000 lumen light on high intensity for over two hours with this battery and it still has over half a charge left. I have found Magicshine product quality to be VERY good - the case is rugged and the mounting method is secure. You definitely get what you pay for with this battery - I highly recommend it! In hindsight, I should have simply bought the whole light/battery from Magicshine originally and been much better off for it.

This battery works with my 2011 era MS 900 GMG 4.5 MagicShine light. Burn time seems about the same or better than with the original battery (2 hours + commute time total). The connector is more "sticky" than the original, so it's tough to disconnect it after rainy rides when my hands are wet. It is more bulky than the original battery and the lighter color makes it stand out compared to the original black battery. The giant velcro strap is, well, giant. The battery won't fall off my bike accidentally any time soon. The LCD readout of capacity remaining is fairly useful and jibes with the colored light on the back of the light itself, so I think it's accurate enough. So far I've only used it on foggy/rainy rides or summer nights. If I see a drastic change while riding in the winter I will edit this review to reflect that. It's a good battery, I'm satisfied with the purchase.

I have 3 batteries for my magicshine headlight & tail light. This one is the most rugged. It actually stays on my bike no matter what. The other batteries have only a single 1/2" flimsy velcro tab which has come off during rides. This 2" velcro will not come off your bike. This battery is smart, with a voltage indicator and it's own charging circuitry. This means that it will take forever to charge but it won't overcharge and the battery lasts way longer. I easily get double the run time from this battery vs my two cheaper ones with the same amperage rating. It's good to have a cheap battery for a spare, but make this beast your primary.

I've thrown away my last Magicshine battery. Spend more on better quality stuff and save your money in the long run.

There's no way to secure the battery to my headtube, so it keeps sliding back on my top tube, both on my symmetrical commuter bike top tube, and my asymmetrical road bike top tube. It'll stay secure, until I hit rough rode. Also, I never get the amount of hours indicated at any of the settings. A waste of money, and it's TOO HEAVY and clunky to top it off. I use it to ride fast in very dark parks with others, so I appreciate the lumens it does support. I'm looking to buy another light system now, as this one has not met my expectations.

I was under the impression this was a housing with 4 18650 cells mounted in the battery holder via springs that could be changed out... it's actually just a normal battery pack (black wrap, fully contained) like the cheap options stuffed inside the housing. My plan was that when the cells die, I just order four more cells and drop them in without soldering. I know this was an assumption, but I wanted to provide this information in the event someone else is thinking the same thing. You'd probably be better off just buying one of the cheaper battery packs for the half the price.

I got this as a backup to my 6 cell Geoman gear battery, now over 1 year old. First impression- larger and heavier than the 6 cell product. Not exactly sure why the digital readout as there were no instructions as to what readings to expect, and the colored button on the light itself seems sufficient. Seems to work fine.

I absolutely love this light and love this battery pack to go with it. It has a lightup screen that you can touch to show you the life left. When the battery is about to die (at least with mine), the lamp starts to flash, and the closer it got to dying, the faster the flash got. Is nice when you have the battery in a location where you can easily look at the screen, but can get annoying after a while if you don't have another battery to replace it with before it dies.