Test/Review of 4Greer 18650 3100mAh (Black)

Batteries and Chargers Rechargeable Batteries
1

4Greer 18650 3100mAh (Black)




Official specifications:

  • 4GREER 18650 Protected High Top Li-ion rechargeable Battery.
  • Capacity: 3100 mAh
  • Max Discharge 6.3A
  • Built in protection circuit and rib sensor for added protection.
  • Highest grade Li-ion and materials allowing high performance in extreme weather conditions.
  • Cold weather tested in the Canadian Arctic.
  • Hot weather tested in Thailand.
  • Weight: 48 Grams






The cell used can be discharged down to 2.5 volt, in my test I only discharges to 2.8 volt, i.e. I do not measure the full capacity. But then, not all lights will be able to use the full capacity.



The packing is not very interesting, because the manufacturer does not have retail sale.























Conclusion

This battery uses a good cell, this secures many things:

  • The batteries does match in capacity, i.e. they can be used in series.
  • The battery is very safe.
  • The battery has the specified capacity.


The PCB current limit is placed about 30% above the cell specification, this is a good value.
All in all a very good battery.



Notes and links

The batteries was supplied by 4Greer for review.

How is the test done and how to read the charts
How is a protected LiIon battery constructed
More about button top and flat top batteries

2

Most batteries based on the Panasonic NCR18650A is good batteries.

4Greer does not do much in LiIon batteries, I only know of two different 18650 batteries.

3

Look good and thanks for the review, HKJ. But are these the most expensive 18650 batteries out there?

No, Only at first glance: $23.95 for one cell in NA. Price for 2+ is $18.95 ea and 10+ for $15.95 ea, all with free shipping. Actually in line or a little cheaper than Redilast or Callies with that factored in, at lease for North America.

Here's another site for UK, I believe? Pretty expensive there.

http://www.inovatech.co.uk/shop/product.php?productid=139

4

Yeah, a bit of price gouging there.. I did the eX-cells with the same cells and top quality PCB for £9.99 each or three for £28.99. It didn't quite work out as I cut costs a little too tight, but a comfortable and sustainable profit could be made selling for around £12.50 each. £22.50 is asking too much.

5

But would you be prepared to do it again?

I imagine there were quite a few hassles.

6

I would be prepared to do it again if I knew I could sell 100 of them within a couple of months for £12.50 a cell + actual postage, the problem is I may only sell 30/40 and be left with loads, I really wouldn't want to drag out the sales as I have lots of other work to focus on too being a student. There were hassles, which made it not really worthwhile for me at the price I was selling them for, and as I was getting a bit of stick already from some for the price (it is BLF) I didn't want to have to raise it for the next batch.

Also, for an online shop with other inventory I see much less of an excuse to raise prices too high, as it's not like selling these as an additional product adds too much to the amount of work in running the business. For these 3100mah based cells with good quality PCB I see £12.50 as a good price for both seller and buyer, and probably £14.95/£15.95 as an expected typical retail price in the UK. £22.50 really is too far in my opinion though.

7

Thank you for the review HKJ.

Excellent as always. Bit pricey for me too, but looks really dependable.