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3.3 out of 5 stars51
3.3 out of 5 stars
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on 13 February 2014
Ultrafire DO NOT make a 4000mAh 18650 - checkout their website.
The extra metal tabs on the terminals indicate that these are recycled cells from a laptop battery, which have been repackaged with some flashy back and gold printed labels

Avoid like the plague!
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on 30 September 2013
delivered on time, at first all seemed well, until I had to recharge, only one of the batteries, would recharge,it wouldn't axccept
any charge at all,
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on 5 February 2014
These cells do not hold 4000mAh at all, they are reclaimed laptop cells. They hold about 1000mAh charge and have no protection at all!
[...]
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on 22 January 2014
I Used these for my cycle commute in to work, the first one developed a rattle after the first ride and became highly intermittant, the second after 3 charges, both now wont even charge.
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on 31 January 2016
NOT 4000 mAh as the title says. Even the "actual capacity 2600mAh" hidden in the product description is wishful thinking.

I wish I'd read the reviews before buying these. They're very obviously poorly re-packaged low-capacity cells that have been salvaged from some other source. The text on the cells I received says they have a "Sheef-life" of 10 years.... Nice. I like my sheefs to last at least a few years.

I stripped off the dodgy plastic wrap under which was another layer marked HBK 18650/12 02 for which I can't find any data online.

Do yourself a favour and spend the extra few quid on some genuine branded cells - NOT Ultrafire, as these seem to be the most common of the fakes. The "candlepower" forum (search for it on google) has a LOT of info on these cells which I wish I'd seen before wasting my money.

In short (which I wouldn't advise!) these are fake, low-capacity and poor quality. Amazon should remove these from sale on their site but hey, it's all profit to them so who cares about the customers, right?
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on 16 March 2014
I am writing this late review because I had to give time to see if the batteries are working properly. Unfortunately after the 3rd re-charging cycle the batteries are not working any more, I've tried to recharge with different charger and no success.

No complains regarding the sellers services, but I would not recommend the product.

Thanks.
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on 22 January 2014
These cells are not protected against under voltage which makes them fairly useless as Li-ion batteries for use in anything that doesn't offer protection itself. Li-ion batteries shouldn't be discharged below 3V without risking permanent damage and shortening of their life. These will happily go way below 3V.
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I bought a few sets of these for torches and other items mostly as back up batteries.
Ran them through a capacity checker and both cells were barely over 1000mAh about a quarter of the quoted capacity.

Clearly something is going on these are not high capacity cells at all. On the upside they do work (at least for a time) run time won't be amazing though. Labelling is clearly misleading on these batteries. The usual rule of if it's too cheap...if you want high capacity 18650 cells you'll need to spend more on a reputable product.
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on 21 March 2015
As other reviewers have pointed out these are reclaimed batteries rather than new. Without stripping the wrapping off it is not possible to verify whether they are genuine UltraFire, however it is unlikely as UltraFire normally have their name across the bottom surface of the battery (negative contact face). The batteries are shorter than the genuine ones which have protective circuitry and are 67mm long, therefore it is unlikely that these are protected. The title states "UltraFire BRC 18650 3.7V Rechargeable 4000mAh " BUT the Product Description further down states "Actual Capacity: 3.7V 2600mAh". So which is true? Delivery from LightsCastle is from the Netherlands and takes several days. Whether it is safe to use these unprotected, reclaimed, questionable capacity batteries is questionable. As far as I'm concerned I'm buying guaranteed, protected, genuine, higher capacity replacements from a reputable UK supplier at less cost per unit. I wish I had looked there first rather than buying this trash.
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on 4 July 2013
very disappointed
not were near 4.000 mAh only about 2.250. very disappointed and i will no by again , and try different make.
22 comments|9 people found this helpful. Was this review helpful to you?YesNoReport abuse

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