I have recently been sent a number of 4GREER 3100mAh protected 18650 batteries for review.
4GREER informs me that these 3100mAh batteries were specially made, based on the popular Panasonic NCR18650A internal cell. The protection circuit, protection plate, as well as high-top contact plate and packaging, are all unique for the 4GREER brand. They have also emphasized to me their optimization for performance in extreme weather conditions, both in very cold and hot climates.
For those of you who are not familiar with 4GREER (which apparently stands for "4 Genuine, Robust, Efficient, Excellence, Reliable" products), they are a Canadian company that manufacturers batteries and flashlights. They have been around for about 3 years now, and specialize in products aimed at law enforcement, military, medical, etc. I had previously examined their earlier 2400mAh cells.
Note that this mini-review will be done in the style of my earlier 4GREER and Redilast quick battery comparisons. Most of the other batteries compared here will likely be familiar to CPFers. Also note that I am not going to be cutting up any batteries – I’m simply going to compare the apparent capacities in my standard test bed. And I will leave the (incredibly valuable) detailed voltage/current testing to those who have the necessary equipment, like HKJ.
4GREER reports the following characteristics for these cells:
- Nominal Voltage: 3.7V
- Fully charged, without load, voltage should read 4.18V DC
- Nominal Capacity (min.): 3050mAh
- Nominal Capacity (typ.): 3100mAh
- Diameter (Max): 18.6mm
- Length (Max): 69.2mm
- Approx.Weight: 48g
- MSRP: $24
As you can see, these 4GREER 3100mAh cells have a small button top, and should therefore work fine in lights that have a physical reverse-polarity protection feature (or that otherwise need raised rops). How do they compare to other cells?
From left to right, 4GREER 3100mAh, 4GREER 2400mAh, AW 2200mAh, AW 2600mAh, Redilast 2600mAh, Redilast 2900mAh, Xtar 3100mAh, 4GREER 3100mAh.
The purpose of the above is to show you the height and button-top differences of the 4GREER cells compared to others I own. The older AW 2200mAh cells and the Eagletac 2400mAh cells have the classic small button-top, and are of course shorter than these newer high-capacity cells. The older 4GREER 2400mAh have a traditional small button top, and are quite tall for their class. The AW 2600mAh cells have flat-tops that don’t project beyond the wrapping. The Redilast 2600mAh and 2900mAh cells have a wide raised top (i.e. wide button-top). The Xtar 3100mAh (also built around the Panasonic NCR18650A) has a small button-top.
Here is how they all compare in weight and height (average of multiple samples given):
- AW 18650 2200mAh small button-top – 45.9g, 67.4mm
- AW 18650 2600mAh flat-top – 46.4g, 67.8mm
- EagleTac 2400mAh small button-top – 46.7g, 68.8mm
- 4GREER 2400mAh small button-top - 48.6g, 69.2mm
- Redilast 2600mAh wide button-top – 47.2g, 68.5mm
- Redilast 2900mAh wide button-top – 45.7g, 68.9mm
- Xtar 3100mAh small button-top – 46.3g, 68.6mm
- 4GREER 3100mAh small button-top – 45.7g, 69.0mm
The 4GREER cells are a reasonable length for 3100mAh cells with a button top – I am glad to see they are shorter than the earlier 2400mAh cells.
Testing Method and Results
My standard test bed for all Li-ion batteries is the original JetBeam IBS circuit. I possess the first-generation IBS circuit in all three body types (Jet-I, Jet-II and Jet-III), which allows me to similarly compare 14500, 16340 (RCR), 14670, 17670, and 18650. I like using this circuit for comparison testing because it is optimized for 3.7V Li-ion, reasonably heavily-driven at max output, and runs fully-regulated.
To test batteries, I charge up each new battery I receive on my Pila to 4.18V, and run on the appropriate IBS light at 100% until the protection circuit kicks in. This gives me an easy way to estimate the capacity of new cells as they arrive (as well as periodically monitor their health over time). FYI, in my standard reviews, I only use "typically" performing AW 18650 2200mAh small button-top cells (i.e. cells that perform around the average of all samples I have bought).
The 4GREER cells are performing well – there is good consistency between my four samples. All 4GREER 3100mAh cells consistently exceeded my Redilast 2900mAh cells. I do not know at what voltage the protection circuit is cutting in at, but I suspect it is comparable to most other cells.
To see how they compare in a light that cannot maintain flat stabilization at high drive currents, below are runtimes for 3x 18650 cells in the Xtar S1:
The 4GREER 3100mAh runtimes look remarkably similar to the Redilast 2900mAh, just with proportionately greater runtime, as you would expect.
Again, I don’t know what the internal construction of the cells are like, but my 4GREER samples seem of consistent and good quality in their external presentation (i.e. no bulging contact surfaces, centered raised-tops, etc.).
Hopefully, you found the quick runtime comparisons useful. I look forward seeing more detailed analyses of these cells from those who have the necessary equipment and expertise.
4GREER batteries were provided by Kit-Tronics.com for review.