I've done it again, I've purchased another flashlight. I seem to be getting quite a collection. This time its the Aurora AK-P7-5 HA-III SSC P7-C 5-Mode 900-Lumen LED Flashlight with Assault Crown (1*18650), again from dealextreme.

http://www.dealextreme.com/details.dx/sku.15692


The Aurora AK-PF-5 (with an aggressive stainless steel assault crown) below a Fenix T1

Quality and finish (HA-III) seem to be good/excellent for a $40 flashlight and it very powerful as you can see below



Fenix T1 (Turbo mode) left and Aurora AK-P7-5 right (the SSC P7-C High Powered LED emitter outclasses the excellent Fenix T1s Cree Q5 @ about 220 lumen)

The Aurora weighs in at 180 grams compared to the Fenix at 190 grams despite being just slightly larger. The Aurora has 5 modes in the following order;

Medium > Low > high > Rapid Flash > SOS

Low mode should give around 8-10 hrs use at around 50-60 lumen using a 18650 2500mA 3.7 Volt rechargable Cell. This is more than enough light to navigate easily over some difficult terrain.

So far the only downside is that the Aurora does not stand up vertically as the rubber clicky protrudes and there is no provision for an attachment for a lanyard.

A reasonably well made SSC-P7 flashlight with good mode setting features for $40 seems to be pretty good value for money. The Aurora might not be as tough as the Fenix T1 but then there aren't many that are. The Aurora would make an excellent compact and very powerful vehicle and home flashlight.

Both the Fenix T1 and Aurora AK-P7-5 fit the large flashlight holster from dealextreme.

http://www.dealextreme.com/details.dx/sku.1152

I'm viewing the Aurora's description on dealextreme.com, and it says that the Aurora is "Powered by 1 x 18650 battery".

What is that? From a search on Google I'm thinking that might be a rechargable Li-Ion battery of some kind.

The 18650 battery is a lithium ion rechargeable cell which can hold about 9WHrs i.e approx 3.7V x 2.5A/Hrs. A typical AA NiMh rechargeable cell will have a capacity around 3.0 WHrs i.e approx 1.2V x 2.5A/Hrs.

Typically the 18650 cells are found in many Laptop Lithium ion batteries. A Laptop manufacturer will quote 6 cell laptop battery for example.

Both can be recharged many hundreds of times although with the AA and AAA NiMh rechargeables they can be recharged up to 500-1000 times.

So the Lithium 18650 cell would have the equivalent energy capacity of 3 AA NiMh 2500 mA/hr cells but weighs less than half the weight of the same 3 cells.

18650 cell weighs around 45 gms
3 AA NiMh cells weighs around 88 grams

The 18650 cell is also capable of delivering very high drain current values allowing up to around 3A to be drawn. This wouldn't really be possible with AAs arranged in series as the AA own internal resistance would limit the drain current. NiMh AAs are superior to Alkaline AA in this respect though.

When using 18650 it is always advisable to use protected 18650. Protected lithium cells have a little circuit board built into the cell to shut the cell down if it detects a short circuit. Without this protection the cell could overheat wilst delivering to much current and could catch fire and explode.

18650 are becoming easily available along with 18650 chargers, although possibly not from a local source. 18650 protected cells can cost around $5-13 each and the charger cost around $12-18.

http://www.dealextreme.com/details.dx/sku.5790

http://www.dealextreme.com/details.dx/sku.1251

http://www.lighthound.com/AW-18650-Protected-2200-mAh-Rechargeable-Lithium-Battery_p_20-105.html These cells are probably better quality than the Trustfire cells.

http://www.lighthound.com/Ultrafire-WF-1...r_p_6-2279.html

I normally keep around half a dozen 18650 cells available and in an emergency would recharge them with a solar charger.