Showing posts with label 18650. Show all posts
Showing posts with label 18650. Show all posts

Tuesday, July 5, 2011

18650 BATTERY COMPARISON

18650 BATTERY COMPARISON

Review of Protected Soshine 2800mah 18650 and Protected Trustfire 2400mah 18650



BACKGROUND

The Ultrafire WF504B which was reviewed earlier, uses a 18650 battery.  I also plan on posting up reviews of some other 18650 flashlights in future, so I thought it would be a good to do an article on these batteries.

For those of you not familiar with the term, '18650' refers to a lithium ion battery size.  In theory the battery should measure 18mmx65mm and be cylindrical (I believe the '0' at the end of '18650' is a reference to the shape).  You will often find there is some variation in the actual size of 18650 batteries.  Some 18650 have a protection circuit which will add further length.  Labels and packaging can also affect the size.

18650 batteries are most commonly found inside laptop battery packs, but they have also been taken up by the flashlight community for powering flashlights.  The benefit of these batteries are they can be very energy dense... they can hold alot of energy for it's size.

Before using lithium-ion (li-ion) batteries, it is important to familiarise yourself with the different sorts of li-ion batteries, how to use them safely and how to prolong the life of the batteries.  If care is not taken, some types of li-ion batteries can vent and explode!  At the end of this post, I've included a few articles and threads with further info on li-ion batteries.

I received a couple of different 18650 batteries from Dealextreme for review.  Included were the protected Soshine 2800mah and protected Trustfire 2400mah (black/red/flames packaging).

I was interested to compare these to some other 18650 batteries I have, including the same Trustfire 2400mah, but older and heavily used.


PACKAGING

The packaging for the Protected 2400mah Trustfire batteries is quite rudimentary.  They come in a two pack with shrink wrap around the outside.



The packaging for the Protected 2800mah Soshine batteries are more professional.  They come in a two pack in a clamshell packaging.  A bonus battery case is included.




TESTING METHODOLOGY

These batteries were all initially charged on a Pila IBC charger using the same channel on the charger.  They were then discharged on an Accucell 6 charger at different discharge rates (0.2A and 1.0A).  The Accucell 6 discharges the cell until they reach 3.0V (under load).  You should note some batteries such as the panasonic NCR18650 and NCR18650a can be discharged down to 2.5V.  Since the Accucell terminates at 3.0V, in theory these types of batteries can still be discharged slightly further and provide more capacity. The redilast 2900mah are based on the panasonic ncr18650.

I have included a rough estimate on how heavily used the various batteries are. 

I have to say the older batteries have seen some significant use and moderate abuse.  The unprotected blue 2400mah ultrafire and protected 2400mah trustfire (X), have seen quite a few cycles, some of which they were deeply discharged.  The more heavily used trustfire (X) and was then used with trustfire (Y) in a 2x18650 flashlight (only for a few cyles).  Trustfire (Y) had not been as heavily used as trustfire (X).  Do note; it is NOT recommended to use two poorly matched batteries in a multi-cell light.  I feel this incorrect use of these two batteries, may have result in some damage to both the trustfire cells.


RESULTS






CONCLUSIONS

Under lower current draw (0.2A) conditions the Black/red/flames Trustfire do provide close to the advertised capacity.  Under 1A current draw they still provide around 2200mah or more.  There is some doubt on how well these batteries keep that capacity after many cycles.  My older black/red/flames trustfire have lost a significant amount of capacity, with one developing high internal resistance.  I do have to say these older batteries have been through some abuse. 

For under $10 for two (shipped), they do represent a good buy, if you accept they may not last as long.  (It would be interesting to test my redilast 2900mah after they have been through a similar about of cycles and abuse, to see if these more expensive cells do indeed last longer.)  You should also note some people report there to be variation between various batches of these same batteries.

In my samples of the soshine 2800mah batteries, they are quite short of their rated capacity.  In my tests I only get around 2400mah from these cells.  I have a feeling I have gotten an older batch.  After charging the batteries to 4.20V, they do drop down to 4.13V after resting for a period.  This is a significant drop in voltage and may indicate they are older or used batteries.  Considering the soshine 2800mah are more expensive than the trustfire 2400mah, I feel I can not recommend these batteries.  There are better buys elsewhere.


LINKS:

Here a few articles on 18650 batteries

http://batteryuniversity.com/learn/article/lithium_ion_safety_concerns
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
http://batteryuniversity.com/learn/article/lithium_based_batteries


http://www.candlepowerforums.com/vb/showthread.php?312835-Beyond-the-basics-for-Li-ion-safety
http://www.candlepowerforums.com/vb/showthread.php?178133-Are-Li-Ion-Batteries-really-dangerous
http://www.candlepowerforums.com/vb/showthread.php?35282-Li-Ion-FAQ-amp-Safety

http://www.redilast.com/index.php?option=com_content&view=article&id=51&Itemid=85
http://budgetlightforum.com/node/1825



Links for buying the protected soshine 2800mah and protected Trustfire 2400mah:


http://www.dealextreme.com/p/soshine-protected-18650-3-7v-2800mah-lithium-batteries-with-case-black-2-battry-pack-31896
http://www.dealextreme.com/p/trustfire-protected-18650-3-7v-true-2400mah-rechargeable-lithium-batteries-2-pack-20392

Monday, May 2, 2011

UltraFire WF504B XM-L T6 (5 Mode) - Silver [REVIEW]

UltraFire WF504B XM-L T6 (5 Mode) [REVIEW]
 

BACKGROUND

I received the Silver Ultrafire WF504B (with XML T6 and 5 modes) from Dealextreme for review purposes.  Luckily it came in time before the Easter weekend, where I took it along with me for a night time bush walk up a small mountain.  The trek took 2.5 hours to reach the summit outlook where we watched the sunrise in the east.  Despite waking up very early in the morning and being sleep deprived, watching the sun break through the clouds and haze was totally worth it.



I will comment later on how the flashlight performed during this little night time adventure.


SPECIFICATIONS (AS GIVEN BY DEALEXTREME)

Brand:  UltraFire
Model:  WF504B
Emitter Brand/Type:  CREE
Emitter BIN:  XM-L T6
Color BIN:  White
Total Emitters:  1
Battery Configurations:  1 x 18650 Rechargeable Battery (not included)
Voltage Input:  2.8~4.2V
Switch Type:  Clicky/Clickie
Switch Location:  Tail-cap
Modes:  5
Mode Memory:  Yes
Mode Arrangement:  Low > Mid > High > Fast Strobe > SOS
Circuitry:  Digital Regulated 1400mA Current Output
Brightness:  510 lumens maximum brightness (manufacturer rated)
Runtime:  60min at high mode
Lens:  Coated Glass Lens
Reflector:  Aluminum Textured/OP Reflector
Dimensions: 5.35 in x 1.26 in x 1.26 in (13.6 cm x 3.2 cm x 3.2 cm)
Weight: 3.77 oz (107 g)
Cost:  $20.40 (including shipping)
Web address:  http://www.dealextreme.com/p/ultrafire-wf504b-xm-lt6-5-mode-510-lumen-white-led-flashlight-with-strap-silver-1-x-18650-57096


PACKAGING AND ACCESSORIES

The Ultrafire WF504B comes packaged quite plainly, wrapped in bubble wrap.  Included is a black wrist strap of average quality.


DESIGN AND BUILD

The Ultrafire WF504B is flashlight host capable of using P60 sized drop-ins.  For more information on what P60 drop-ins are, I would recommend you read this.  Included in this particular package is a 5-mode drop-in with a CREE XM-L T6 LED.

P60 host components - head, drop-in, body, tail-cap

Upon receiving the light I did notice a few minor points that put me off.  For a start there was a great big dirty finger print on the reflector.  The o-rings were already lubed, however the threads were not.  In my sample there is a small machining spur on the tail-cap.  These are minor issues that are easily solved but I did want to point them out.  Considering this is a 'budget flashlight', I am more forgiving about these points.

R2 written on the body (look under the symbol to the right of CREE for R2)
  The body of this light says CREE R2 which is quite misleading.  I suspect ultrafire has used their standard Ultrafire WF504B host and has simply changed the drop-in to an XM-L T6 drop-in.  The emitter in the drop-in does appear to be an XML LED.

OP reflector and CREE XM-L LED

This version of the Ultrafire WF504B comes with an OP (orange peel) reflector.

Around the base of the head is a hexagonal ring which prevents the light from rolling around, when horizontal.  This 'anti-roll' feature is useful to have.

Hexagonal ring at the end of the head which acts as an anti-roll feature

Knurling is present on the body and tail-cap of the flashlight.  I find this knurling to be comfortable, not overly aggressive or rough, whilst still providing adequate grip.

The tail cap has a reverse clicky.  The clicky button is slightly recessed, allowing you to tail stand the light.  Personally, I prefer a light that can tail stand as it allows you to use the ceiling bounce for general lighting purposes.

Recessed reverse clicky switch.  Note there are two holes for threading through the lanyard

With this 'silver' version of the Ultrafire WF504B, it is not annodised.  This will have different wear characteristics to an annodised version.

This flashlight lacks the ability for 'tail-cap lockout'. 'Tail-cap lockout' refers to a feature where you can prevent the flashlight from accidentally switching on, by slightly untwisting the tail-cap.  The threads of the flashlight need to be annodised for this feature to be present.   

There is a black annodised version of this flashlight, but from the pictures on the website, the tail-cap threads appear unannodised and I would also suspect it also lacks tail-cap lockout.  Without this other light in hand I can not confirm for sure.

I've found when using the high mode, the head of the flashlight can get quite hot, especially if you leave the light tail standing indoors for a prolonged period.  When using it outside in a cool environment and holding the light with my hand, the flashlight head remains a comfortable temperature. 

A common recommendation with P60 drop-ins is to add copper tape or aluminium foil around the drop-in.  This allows better transfer of heat from the drop-in to the body of the flashlight.

Aluminum foil added to the P60 drop-in.  This allows better transfer of heat to the body of the flashlight



LED, BRIGHTNESS AND BEAM CHARACTERISTICS

The Ultrafire WF504B features an XM-L T6 LED.  For those of you who are not aware, XM-L is a fairly new series of LEDs produced by CREE.  According to CREE the XML is ~20% more efficient than the XPG at the same current.  The XML is also capable of handling higher currents (up to 3A) than the XPE, XRE or XPG LEDs.  This translates to a higher brightness if the LED is driven hard enough. 

Tail-cap readings of the flashlight with a fully charged Redilast 2900mah 18650 battery were:
high - 1.49A
med  - 0.64A
low  - 0.07A

From the CREE data sheet expected LED lumens at these currents would be:
high: ~530 lumens
medium:  ~250 lumens
low:  ?? - hard to determine via data sheet, but by eye, I would estimate ~10-20 lumens


Take these readings and calculations with a grain of salt.  I do have to say, my DMM (digital multimeter) is fairly cheap and is not calibrated, so I would consider the tail-cap readings as estimates only.  The Redilast battery has only been through a few usage cycles, tail-cap readings with some older and heavily used trustfire batteries were lower (some as low as 1.1A-1.2A).  The high and medium lumen ratings are 'LED lumens' based on calculations, not 'out the front' (OTF) lumens.

In theory, the XM-L could be driven much harder and brighter on high (~900 lumens @ 3.0A).  However you would get issues with heat management and reduced run-times.

The XML LEDs have a larger die than XPG, XRE or XPE LEDs.  This translates to a beam that tends to be more floody with a larger hotspot (if using the same sized reflector).  The max brightness of the XML tends to be higher than the afore mentioned LEDs, this helps to make up for some of the loss in throw.

I find the Ultrafire WF504B XML gives a nice floody wall of light that lights up the first 10-20 metres. It doesn't tend to throw very well, and I find the hotspot gets lost if you are looking at something more than ~50m away.  I might see if I can find a SMO (smooth) reflector to replace into this light.  A SMO reflector tends to provide more throw than an OP reflector.

My sample of this flashlight has a nice clean white tint.

Beamshots were taken at ~20 metres away.  ISO 400, f 2.0, 2" .  In person, I feel the lights are more floody than what appears in the beamshots.

High

Medium

Low

Control


USER INTERFACE AND OUTPUTS

This version of the Ultrafire WF504B has 5 modes; high, medium, low, fast strobe and SOS.  To switch between the modes you need to turn the light off and on within ~1 second.  A quick 'half-press' while the flashlight is turned on, will also allow you to cycle through the modes.  If you leave the light off for more than ~2 seconds, it will remember the last mode and turn on again in that mode.

Unfortunately due to the user interface, you will need to cycle past strobe and SOS whenever you want to go from lower mode to a higher mode.  This can be quite annoying at times.



If you do not like multi-mode lights, do note that Dealextreme offer a single mode version of the flashlight that runs only on high.

http://www.dealextreme.com/p/ultrafire-wf504b-xm-lt6-510-lumen-white-led-flashlight-with-strap-silver-1-x-18650-57098
http://www.dealextreme.com/p/ultrafire-wf504b-xm-lt6-510-lumen-white-led-flashlight-with-strap-black-1-x-18650-57097

I do note there is PWM regulation on the medium and low modes.  During actual usage, I find the PWM unnoticeable on low and just barely noticeable on medium. 



PERFORMANCE DURING MY HIKE

During my night time walk, there were sections that were very steep, requiring both hands and usage of a headlamp would be recommended. But otherwise, I was quite happy with the performance of the Ultrafire 504B XML T6, as a hand held held flashlight.  I was at the front of our group and I found the Ultrafire flashlight provided a nice wall of light for lighting up the trail ahead.

Portion of the trek where ascent is near vertical. Chain handrail is needed for support.

During most of the walk I used the Ultrafire WF504B XML in medium mode.  I found medium offered an adequate amount of brightness for lighting up the trail.  Towards the end of the trek, there was a lot of fog and haze which absorbs a lot of the light.  During this period I ran the light on high for max brightness.

Haze and fog during the night time walk

In theory medium mode would have lasted me until the end of the 2.5 hour trek up.  However when I started using high more often, I changed the battery as I did not want to overdischarge the li-ion battery.  During the walk back down, the sun was already up so no flashlights or headlamps were required (unfortunately).

First light

Sunrise!



CONCLUSIONS

For ~$20 shipped the Ultrafire WF504B XML T6 is a reasonable buy.  For that price you get one of the latest XM-L drop-ins and a P60 flashlight host.  Being a P60 flashlight host means it is easy if you want to upgrade or switch emitters... all you need to do is buy a different drop-in.

The XM-L drop-in in the package provides a nice floody wall of light but not much throw.  Driven at ~1.4A on high, it gives an acceptable runtime on high whilst still giving you a good amount of light.  I would consider spacing between high, medium and low modes to be pretty good.  The low is a fairly bright low, so if you prefer low-lows this is not for you. 

Unforunately with the 5 mode version of the Ultrafire WF504B XML T6, you constantly have to cycle past the rarely used strobe and SOS modes when switching from a lower mode to a higher mode.  I would prefer it if dealextreme offered a version with only high/medium/low and NO strobe or SOS modes.




ALTERNATIVES TO CONSIDER

I've never really gotten into p60 hosts before; this is my first p60 host flashlight.  However some other P60 hosts brands you could consider are solarforce (these have a good reputation of price vs quality) or the original surefire hosts ($$$).

ADDITIONAL PHOTOS

Ultrafire WF504B at the summit outlook

P60 components (alternate views)



[If you have any trouble understand some of the flashlight terms used in this post, see my 'links' page for a link to a glossary of terms]