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Amazingly Hi-Intensity LED Flashlights


These are not like your old flashlights!

LED Flashlights have come a long way, and now surpass the efficiency of Compact Fluorescent lights. High Output LEDs started showing up a couple of years ago, and at the 2007 Pacificon Hamfest FrankK found one of the new Cree XR-E LED flashlights that puts out about 160 Lumens (probably rated at the emitter, actual light output may be lower, link below). This is a lot of light, it is so bright that you have to be careful not to look directly into the beam. This is brighter than any other flashlight I had previously, including 3D Maglites with Krypton bulbs!! This from a flashlight that is only 3" long and less than 1" in diameter! This flashlight also came with a 3.6V 1000mah Li-Ion rechargeable battery and charger. This changes everything. Now you can easily carry and use your BRIGHT flashlight every day and recharge it, and if you don't use it for months it will still be charged and ready to go. This flashlight also came with an AA body tube that takes 2 AA batteries. So in an emergency, if your Li-Ion can't be recharged you can either use disposable CR123's or switch to readily available AA batteries.


There are also now LED modules for popular flashlights such as the Surefires or Maglites. I have one for my Surefire 6P. It has hi-medium-low-flash modes and a claimed 180 lumen output on strobe mode. Update on Ultrafire 4-mode drop-in for Surefire: It fits into my old round-body P6, and works fine. It is not quite as bright as the above 160 lumen light, at least on constant modes. On the strobe mode it might be comparable. The user interface is a cycle that seems to have a long term memory. Each time the light is powered it moves to the next setting in the cycle. It offers a much longer runtime than the stock bulb, and higher lumen output. The incandescent bulb puts out a much wider spectral range which in some applications is important. The LED offers a much longer bulb life, the incandescent bulbs need to be replaced periodically, and they tend to darken with time before they fail. There are many drop-ins for the Surefire and the Maglites, so shop around. Prices vary significantly also, up to $50 for the latest super-bright LED.

One thing to consider when choosing a flashlight is the usage pattern and select an appropriate battery type for it. Will it be used daily or will it be stored for emergency use? Alkaline batteries should not be stored in a flashlight for emergency use - they tend to leak and ruin the flashlight as well as not being charged and ready when the need arises. Lithium batteries hold their energy much better and tend not to leak. A flashlight that is used daily should probably have rechargeable batteries - either NiMh or Lithium Ion. The problem with regular NiMh is they self discharge quickly. So they are only good for flashlights that are recharged every week or two. Lithium rechargeables hold their charge extremely well and so are better for less often charged uses. There is a new battery out which is generally referred to as a Nickel Metal HYBRID. These are NiMH batteries with a slightly different chemistry that makes them hold their charge for MUCH longer periods. In a year they claim to lose only 25% or so of their charge. They are a little lower capacity (2100 maH). Examples include Sanyo ENELOOPs and others (see below). So, the best battery for an emergency use flashlight is generally Lithium batteries. The Eveready Lithium AA batteries are good (if the flashlight is rated for their 1.7V output), or select a flashlight that uses the CR123A or other Lithium primary or rechargeable cells.

One term you will run across on the battery discussions is EDC which stands for Every Day Carry, generally applied to a small convenient to carry flashlight. Throwers refers to flashlights that are good at long range beams for lighting up something a ways away. These have larger deeper reflectors to catch light from the emitter, which is another name for the LED. Tactical lights are bright, sturdy lights that can be used to hit with if needed, usually with large reflectors, good beams, and lithium batteries.

Measuring flashlight light output is a complex and confusing business. Without getting into all that, a useful thing to know is the total light output of a flashlight, which is generally expressed in Lumens. This does not specify how spread out or focussed the light is, rather it is a measurement of the total output. A light for close work will have a very broad even beam with no "throw", while a light for searching will have a tight focussed beam with good "throw" and a spill beam that may be dim or moderately bright, depending on the reflector and/or optic design. Manufacturers of flashlights often use the Lumen ratings of the emitter LED rather than the flashlight output, which will be lower due to small losses in the reflector/optic and lens, so comparing values from different manufacturers may be somewhat misleading. Still it is a useful guide. Refer to reviews on Candlepower Forums for actual comparisons. There is a chart below showing some Lumens per watt ratings of various sources. A present (11/2007) day LED can produce about 250 Lumens with 3 watts. Note that the Lumen per watt ratings are generally specified for 1 watt, and the efficiency goes down slightly at the 3 watt level.

Light Efficiency - Lumens/watt


Light Output - Lumens, Hours


Every Day Carry Flashlights

These vary a bit depending on what you are willing to carry, but for most of us a single 123 Lithium battery or single AA battery flashlight will do the job. With the available LEDs the light output can be up to around 100-200 Lumens, though a bit less will help lengthen the battery life. Carried on the pocket or belt or in a purse or backpack these lights are always available and frequently used. The light head diameter is usually the same as the battery tube, or very slightly larger, facilitating convenient carry. With a rechargeable battery setup you can use it every day if needed, and recharge it so that it always has full brightness and capacity. Lithium rechargeables are excellent, or the nickel metal hybrids, so when you don't use it for a couple of weeks it is still ready to go. A model that has several output levels may be more useful and will extend battery life. Some models also have a red LED for low illumination while preserving night vision. Tail standing can be useful to use the light like a candle, illuminating an area by bouncing from the ceiling. Be sure you understand the battery compatibility. Some 123 lights can handle rechargeables and some cannot. Some AA lights can handle the 3.7V lithium rechargeables or 1.7V lithium non-rechargeables, others cannot. A good choice for an AA type flashlight is to use Nickel Metal Hybrid rechargeables, but the light must work well on their lower 1.2V output.. Another choice is to use 3.0V or 3.7V lithium rechargeables, but make sure the light you choose will handle their voltage which is slightly higher than the 3V lithium non rechargeable batteries. Alkaline AAs are probably not a great choice unless the user is tending them as they leak and ruin the flashlight. Non rechargeable lithium 123 batteries don't leak but cost more if the light is used a lot. They are a great choice for low usage levels. Here are some examples, in no particular order:


My search for an EDC flashlight started with the acquisition of the 160 lumen Cree light discussed above. This light is pretty amazing, with a very bright beam from a single CR123 cell, rechargeable or primary. I have used this as my every day carry light since purchasing it some weeks ago. I can use it every day, and charge it every night, so it is always fully ready to go at maximum light output. This is a good little light, so why am I still looking? I really like the high output, and the small size. I like the rechargeable and primary battery capability. What I miss in this light is a low power setting. It is either off or really bright. I have not tested it, but I suspect it will only last an hour or even less in this mode. For many purposes it is brighter than it needs to be. I would like a couple more brightness levels with a good UI (User Interface). I purchased a few 3.7V 900mah lithium ion cells for my existing light. I would like to be able to use them in any new light. I would like to have at least 160 lumens, maybe even 200 lumens available, but be able to readily use less light much of the time (say 200/50/10 lumens). A RED led low output option would also be very nice.

I've looked at quite a few lights that come close. But there is always something not meeting my goals. Fenix's won't take the 3.7V cells. Olight looks wonderful but no 3.7's. So I am still looking..

Another approach to an EDC (every day carry) flashlight is a single AA model. These have a bit lower output than a CR123 battery flashlight, but still exceed 100 lumens in some models, and even 50 lumens is adequate for many purposes. (Keep in mind that the Surefire P6 is rated at 60 lumens, and this outperformed the old 5D Maglites, so 50 lumens is a lot of light for a flashlight). Let's look at an inexpensive high performance AA light, the Ultrafire C3 Cree, available for less than $20. This light has approximately 100 lumen output, which is quite high for a single AA light. It uses a single-mode on/off circuit. It is regulated and runs down to 0.8V so it will run well from NiMH rechargeables. Alkaline AAs also work, but I don't recommend them due to their propensity for leaking and ruining the light, and their poor performance under heavy load. It will also accept 3.7V lithium ion rechargeables for longer runtimes, and there is a 2xAA body extension tube for longer runtimes with standard NiMH batteries. The light output is regulated and does not vary much with battery voltage. This flashlight draws over 1A from a 1.5V AA, so alkalines are going to have some problem handling the load, they will do better with the 2xAA body tube which reduces current draw and extends runtime at the same light output. Lithium non-rechargeable AA batteries would be a great choice for emergency/low usage. The NiMH Hybrid (low self-discharge) batteries would be a great choice here for a rechargeable setup. Comments from Candlepower forums indicate that some batteries won't fit due to diameter or length constraints, so some high capacity NiMH and protected 14500 (rechargeable lithium ion) may not fit. Note that this light will overdischarge an unprotected 14500 cell so this is not a good choice. For me, this is a good light for NiMH or Lithium primary batteries - the only feature I would like to add is a low output mode. For most folks this is a good flashlight, however, and makes a good gift. Include a few Lithium AA primary batteries or NiMH Hybrid batteries and charger for a full gift set.


Here are some other low-cost AA lights that seem to be getting some good reviews in the under $20 category (considerably under):


Moving up the price scale slightly in AA EDC flashlights we find a unit that adds a low output mode. This dual output level light from Lumapower runs on NiMH, Alkaline, Lithium primaries or Li-Ion rechargeables and offers runtimes from about one to two hours on high, and up to 15 on low. It features an SSC P4 high efficiency LED and an orange peel reflector for a smooth pattern. The tail clicky switch cycles through the two light levels and off, and can be twisted to lock off completely for travel. Priced in the low $30's.


The Fenix L1S is also priced in the low 30's and has a tail click on/off. The two light levels are selected by rotating the bezel. 40 lumens high, 10 low. Runtime 3 hours (high, NiMH, 10 low).


In the mid $20 range we can put a Terralux LED drop-in kit into a Minimag 2xAA and have a very nice light at 40-50 emitter luments. If you have the Minimag already, this drop-in is even more economical at about $15. They also have red, green, UV and lower and higher powers of white LEDs. The TLE-5 is a good compromise of brightness and runtime, advertising about 30 hours of runtime. More on these dropin upgrades later in this page. Note this is a 2xAA light rather than 1xAA, but a belt sheath or large pocket can accomodate this.


Continuing up the price scale we find a light with a sophisticated variable output user interface in the Olight T15. Turn the head to select between the 5 output levels, switch the tail clicky to turn on/off and select between strobe or SOS modes. This is simpler than it sounds, as the tail click switch turns on and off, the strobe and SOS can be reached by lightly pressing the tail after the light is on, so they never need to be used or cycled through. The brightness is controlled by the bezel switch. Each 1/8 turn loosen/tighten cycle moves to the next brightness level, and the light remembers the last level when off. The cycle is 90 / 70 / 40 / 20 / 8 lumens, and the runtimes are 0.8 / 2 / 5 / 12 / 25 hours. Strobe runtimes are about double that of continuous. Considering the ready availability of AA batteries, and the ability of this light to conserve them, or put out a bright light, plus strobe and SOS capability that is there but not in your way, this would be a good choice for an EDC light, and a backup light for those times you are carrying a larger tactical light. 4-1/8" x 7/8". About 2 oz.


The next lights are from Fenix. In the last couple of weeks I purchased several Fenix lights for testing. One very impressive light is the single AAA light Fenix calls the L0D. The specific one I have is the Premium seasonal Q4 bin. That means the LED is from the Q4 "bin" of sorting the LEDs. They don't all come out the same, and these sort toward the high end of efficiency. This particular run of lights is a bit higher efficiency than the usual models. This light is very small with a single AAA battery. It turns on and off by "twisting" the body tighter or looser. An "O" ring keeps it from working loose. This type of switch is not quite as convenient, but it makes the light smaller. This light has a multimode interface. When you first turn it on it comes up in medium level, and when you cycle it off and back on within a second or two it goes into the next levels which are low, high, strobe, SOS. The high level is around 75 lumens! This is more light than a standard 4D Maglite !!!!! The light comes with a pocket clip so you can carry it like a pen, and a split ring so you can put it on your keyring. It is type III Hard Anodized so it should hold up well. This light works best with NiMH or Lithium AAA batteries. I really like the low self discharge NiMH such as Eneloops for this light. This light is so small you can nearly lose it in your pocket.

The next two lights are really one light with two body tubes. The Fenix Premium Seasonal 4 in 1 kit includes a voltage boost type head with a Q5 Cree LED. This is the highest common "bin" available today. The R2 "bin" LEDs are just starting to come out, and this is only a marginal improvement over the Q5. R2 based lights have not really come out yet, and they will be quite rare for some time. Q5 is therefore the best for now. So the 4 in 1 Fenix kit also includes an AA body tube (L1D) and a CR123 body tube (P2D), both with their own clicky switches and lanyards, plus a holster. Also included is a plastic body cap to protect the threads on the unused tube, as well as keeping a battery stored in it. A slip-on candle-diffuser is also included, and the light will stand on the tail and make a candle type lantern. The user interface of this light is very nice. There are two controls. One is the tail clicky switch. The other is the head rotation. You can slightly loosen (1/8 turn or so) the head, or tighten it fully. If the head is tight, turning on the light with the clicky will go to the Turbo mode. Bumping the clicky will switch to Strobe mode, and again will go back to Turbo. If the head is loosened slightly the cycle is Low, Medium, High, SOS. Turning the light off for more than a few seconds will revert to the start of the cycle. So you can choose Turbo or Low on this light before lighting it up. The light operates the same on AA or CR123 batteries. The only difference is Turbo mode is a bit brighter with the CR123. The light pattern from the Fenix is excellent. It has a large hotspot with a nice gradient corona and plenty of spill light. You can also get a 2xAA body to fit this head (L2D). It is a very versatile system. This is one of my favorite lights. I carry it configured for single AA use, and carry the 123 body with cell in my briefcase for backup.


The next light is absolutely new, just out. It came out December 10, 2007. It has a single AA for power, and is smaller than the Fenix above in body diameter. It has two LEDs, the main LED is white, about 100 lumens, and the secondary is RED. Both are continuously variable (actually so many steps that it seems continuous). It has a side button which is very convenient. It has a great clip that allows you to put it in your pocket but keep it from falling deep in and getting lost, rather like many folding knives. It has signalling modes so you can send morse code with either the white or red LEDs. I like the red LED to navigate at night and not disturb others. The reflector is smooth, so this light has pretty good throw, but there are some rings in the "white wall" pattern that are not noticeable when the light is in use. This is the LRI Photon Proton PRO.


Other High end single AA Lights, more on these later as this page is updated:



Tactical Flashlights with Good Throw

These are called tactical because they are very tough and bright, and throwers because they put out a piercing long distance beam. Today's LED lights can do this if equipped with the proper reflector. The reflectors and heads on these lights are larger to develop the long range beam. Power sources are usually a pair of CR123 type lithium batteries, either primary or rechargeable. Lower cost models may use two or more C cells. In the past these might have had two D cells or more, but today there is little need for the bulk and weight of the big batteries. Tactical generally refers to bright and very durable/impact resistant. This is the flashlight you want when you have to look for a lost child or pet, or walk through a not so friendly neighborhood at night. This would be a good light to have in each vehicle, and maybe near the front and rear doors of the house. Here are some examples, in no particular order:


Multi Color Special Purpose

There are several flashlights on the market that have more than one color without filters. They have a main beam of either a high output LED or an incandescent bulb, and then one or more sets of lower power LEDs providing either low output floody white or other colors such as red, blue, UV or green. Red is good for maintaining night vision. Blue is good for signalling or spotting blood trails. UV is good for checking for fake money.


Headlamps

If you ever find yourself holding your flashlight in your teeth, or needing both hands plus a light, you need a headlamp. Some folks think they look too nerdy, but coal miners are hardly nerdy, and headlamps just plain work better than handheld lights for a lot of things.

A couple of years ago EricW found an LED headlamp that works very well. It has a 3 watt Luxeon LED and has 3 power levels plus boost, an excellent flip-down diffuser, an adjustable angle head and runs on 3 AA batteries. It is the Petzl MYO XP. Highly Recommended. With the diffuser in place this light has a very floody output that is great for close work, and with the diffuser safely swiveled out of the way the lamp produces a great throw beam with lots of spill for walking or checking out nearby noises. The lamp has a lip to keep light off your glasses, and the small head swivels up and down to put the light where you need it. It runs a very long time on 3 AA batteries. There is a LED upgrade hack for it on Candlepower Forums. Apparently the newer SSC LEDs put out nearly double the light for the same power.. However the original has been adequate, so I have not tried the mod, but I will soon.


Other headlamps that appear interesting include the very highly rated include the Princeton Tec Apex and Apex Pro. These lights have good throw, good flood, and good water seal.


In the high quality and lightweight flood type headlamp category, we have the new Zebralight. Single AA, waterproof, multilevel output, tubular aluminum O ring sealed design. Q5 version emitter 66 / 13 / 2.6 lumens; runtime 2.3 / 19 / 84 hours. The P4 version is a bit less expensive at about 20% less light. 2 0z w/ battery. 120 degree flood. Includes headband, lanyard, hat clip and spare O rings. This is my current favorite in the superlight headlamp category.


The Streamlight Argo is a low cost headlamp that has reasonably good throw, and it can easily be modified with the newest LED.


Modifications and Improvements to Flashlights

There is a 'flashlight hacking' culture that would make the tool-man smile, and you can find some of it on Candlepower Forums∞. Modifications range from drop-ins that require no more effort than changing a bulb to really significant makeovers. Very popular is replacing the stock LEDs with newer more efficient higher output units. If you already have a light from Mag Instruments or Surefire there is a drop-in that will bring your light up to the current state of LED performance. A good candidate for upgrades is the Mini-Mag 2AA light. These can be purchased for under $10 if you don't already have one available for upgrading. You can purchase drop-ins from many vendors. They vary in quality and price, and with LEDs you can get a lot more performance for a few more dollars. The LED drop-ins are also available in colors such as RED to preserve night vision. A white 25 lumen drop-in is about $12, a 50 lumen about $15 and a 100 lumen about $25. I would suggest sticking with the 1-watt 50 lumen drop-ins as the power consumption of a 3 watt drop-in is a bit much for the AA batteries. However, even the 3 watt will last longer than the light originally did, by about a factor of 2, while putting out a great deal more light than the original bulb. The 50 lumen upgrades are even better with a runtime improvement factor of about 6 (while the light output is about four times the original bulb)! Note that the runtime light output is not full the whole time, it drops off at the end. Lumen values are approximate, probably emitter (higher than output).




Flashlight Batteries

There are quite a few batteries used in the new flashlights that were not so common in the past. Here is more info on the ones recently found:

Alkaline Primary Non-Rechargeable

Nickel-Metal Hydride (NiMH)

Nickel-Metal Hybrid -- NEW

Nickel-Cadmium (NiCad)

Lithium-Iron Primary Non-Rechargeable

Lithium Primary Non-Rechargeable

Lithium-Iron Rechargeable

Lithium Ion Rechargeable

More Battery Info

Lithium Battery Safety

Lithium batteries contain a great deal of energy and can explode or burn when mistreated. They should never be shorted or charged improperly. They must be charged on the proper charger designed for them, and with the correct settings. The 3.6/3.7 volt lithium ion batteries have the most energy, and present the greatest risks. The 3.0/3.2V lithium-iron are much safer and do not tend to have the fire/explosion problems, but they do not have as much voltage nor as much energy. Lithium rechargeables can also be damaged by overdischarge. Many lights will continue to operate normally at voltages that are too low for the lithium ion rechargeables, especially when two or more are in series. Protected lithium ion batteries are available that contain circuits to protect against over charge, over discharge, and shorting. These are advised but may not fit in all flashlights due to their slightly greater size. Investigate the compatibility before choosing these combinations.

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AlanB

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