I have five of these things:
Three of them seem tb OK, but two drain the batteries: 2-3 months on the shelf and the batteries are dead.
If it were all 5, I could buy the allegations of a flawed design.
But only 2? I'm thinking some sort of quality control issue.
Does anybody know enough about LED lights in general to ballpark the problem? Not knowing anything, I tend to think it's the screw-on switch/back of the light.
-- Pete Cresswell
I see that you've been shopping at Costco: Junk but cheap. There's no reason you should be using alkaline batteries for high power lighting when LiIon is so much better.
Hmmm.... 108 positive reviews and 255 critical reviews. That should be a clue.
Yep, that's a good possibility. Did you try to measure the current drain when the flashlight was off? Just unscrew the battery cap and attach a DVM ammeter with clipleads. My guess is you'll see a few milliamps drain when off.
That's possible. Inside the tail switch is the on/off, dimmer, and flasher electronics. Here's a teardown of a similar model Duracell
1300 flashlight. I don't think repair is an option because it seems impossible to disassemble without breaking something: Start at 6:00 for the tail switch.-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Someone once handed me one of those cheap $5 or less LED flashlights, and said "What's wrong with this thing?". I took a look. When the switch was turned ON, it worked fine and was bright. When the switch was turned to the OFF position, the LEDs were still lit, but extremely dim.
I have to admit, I was puzzled. I ripped it apart as much as possible. Icould not find any reason. I could only figure that there was some sort of resistance leaking across that switch, but I did not have a multimeter on hand. Plus the switch could not be removed without destroying the flashlight.
I just told the owner to remove the batteries when they are not using it.
On the other hand, I own at least a dozen of those (similar) cheap LED flashlights sold by Walmart for $1. I have no complaints. They work fine, and for the price they are worth buying. The only bad thing is that it costs $1 (or more) to replace the three AAA batteries, so it's ofter cheaper to just buy another flashlight (they come with batteries).
However, "Dollar Tree" has a 4 pack of AAA batts for $1, so that only costs 75 cents for replacement batteries....
use rechargeables.
NT
Per snipped-for-privacy@gmail.com:
I suspect that the issue for most people is dollars-and-cents battery costs, but instead whether-or-not the light works when somebody grabs it during a power failure or something after it's been on the shelf for 3 months.
-- Pete Cresswell
There's another issue, which is what inspired me to get away from alkaline and switch to LiIon and NiMH. Just about every alkaline battery brand that I've tried will leak and rot out the device it is suppose to power. I just recycled yet another 2D Maglite flashlight. At least once per month, I have clean out the guts from a 2way radio, clock, weather station, etc from the crud oozing out of alkaline cells. There must be a better way.
For devices that require AA and AAA cells, I'm using LSD (low self discharge) NiMH cells, mostly Eneloop. I had to use a pair of FRS radios last weekend which were last charged in Dec 2016. 6 months later, the charge indicator showed about 80% charge and they ran the radios all day. Good enough. See charge retention table.
For flashlights, I've almost finished switching to all LiIon batteries, mostly 18650 and 14500. That's about 1/3 of my growing collection of cheap LiIon batteries and flashlights. Why so many? Because most of what arrives is a mixture of not what I ordered, mechanical defects, premature electrical failure, bad design, or bad construction. To insure that things will go awry, I'm also buying nothing but the cheapest LiIon batteries at $0.85/ea for 14500 to $1.30 for 18650. Why buy bottom of the line? Because it's my contention that bottom of the line batteries are a better deal on the basis of cost per energy delivered than buying quality high capacity cells. It will take another 6 months or so to be sure, but so far so good. Cheap 18650 battery capacity at 1.5A, which is at the high end of what a flashlight will draw:
Drivel: There's even a web site for cheap flashlight enthusiasts:
The only fly in the flashlight ointment is the cost of a decent battery charger. Most of the really cheap battery chargers are badly designed, dangerous, or both. For example, this loser sells for about $0.50 with many flashlight and battery combinations: How customs even lets them into the country is a mystery.
Before you buy a charger, check here: Also avoid any dual battery charger with only one LED light. These charge 2 batteries in parallel, which is a rather bad idea, but will work for one battery at a time.
Real LiIon chargers are quite a bit more expensive. These are good so far: $10 $17.20
Bottom line is that you can get a decent bottom of the line flashlight system for: flashlight: $3 to $8 18650 battery: $1.50 Charger $10 ========================== Total $15 (approx) Of course, the expensive charger can be used with multiple flashlights, so the 2nd flashlight will cost only about $5.
For LiIon battery packs with multiple cells, I use a balance charger: The charger is the most important and most expensive part of the system. I built a 10watt LED light, that runs on 11.3VDC, which uses a balance charger.
Oh yes, self discharge. Li-Ion is as good or better than LSD NiMH: See Tables 3 and 5. There's a rumor that storing a LiIon battery at full charge would shorten its useful life. That was certainly a problem with laptop batteries during the 1990's, but seems to have been eliminated in the current offerings.
Anyway, think rechargeable, recycle your alkalines, and return the flashlights to Costco.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
I'd agree, but many of my devices won't run on that voltage. Wireless power monitors and thermometers, for example.
What's your experience with 14500 in single AA flashlights? Mine get hot enough with NiMH. I'm afraid to run them on 4V at 7W. Here's an example:
Lowes has a six-cell 18650 lithium tool battery for $10. Only 1.5AH, but rated for 30 Amps max. Was gonna replace NiCd in an old drill, but I'm procrastinating.
I have one that looks identical except has US plug. Terminates just fine below 4.2V. Doesn't seem to have any of the characteristics shown in the review. I didn't take mine apart.
They even sell blank AA cells (containing a wire from +ve to -ve) for devices that can use one Li cell instead of two alkalines. I use these in an Apple Bluetooth keyboard for example.
Except in Chinese marketing materials :)
I did this with my Ryobi, and use it every day: It used to have 11 stubby NiCD cells, now four 26550 LiIons. Recently reworked with a female balance connector, after it short circuited in a toolbox and burnt one of the wires.
Hobbyking supplied a Turnigy Accucel-6 for $25, which runs nicely off an old laptop power brick.
Clifford Heath.
Most everything that will run on alkaline cells will also run on LSD NiMH cells.
However, you can't just plug in a LiIon cell into a device made for alkaline cells, even if they fit. For example, if you try to replace a common AA alkaline cell with a 14500 LiIon cell, you are replacing a
1.5V cell with a 3.6V cell, which will likely burn out the device. However, you may be able to replace two AA alkaline cells with a single LiIon cell if device will tolerate a 20% increase in battery voltage. Most devices that have a voltage regulator will work nicely. Those without voltage regulators, will overheat.I don't understand. 14500 is the size of a AA cell which applies to alkaline, NiMH, and LiIon, LIPO, LiFePO4, etc, all of which have different terminal voltages. The flashlight appears to be designed for a 14500 size NiMH battery. Running it on a AA alkaline will kill the battery in short order because it can't handle the current. Running it on an LiIon battery will blow it up because it will be over twice the rated voltage. There's no information on the above web site as to whether the light is intended to operate on alkaline, NiMH, or LiIon voltages, but a comment by a user indicating that "7 days on a single AA Enelope" suggests NiMH. Do NOT install a LiIon 14500 cell as it will probably burn out the electronics (also known as the "pill").
The Cree XP-E Q5 LED is designed to operate at about 350ma and will generate about 120 lumens depending on type and bin selection: That's about: 120 lm / (3.6v * 0.35A) = 95 lumens/watt which is consistent with todays LEDs at room temp. There is no way the XP-E Q5 LED will dissipate 7 watts or produce 600+ lumens.
In order to run on a single 1.35V nominal NiMH cell, the flashlight will require a boost converter and a current regulator. Done correctly, these work just fine. Done badly, they get hot and burn up. My guess(tm) is that this flashlight is in the latter category.
It depends on which tool and how the conversion is done. I have several Makita 9.6v nominal power tools, that were intended to run on NiCd or NiMH, now converted to run on 11.3v (3 cells) LiIon cells. I was concerned about the increase in voltage, so I added a series power diode to drop the voltage. Works fine but admittedly does get warm when run heavily. Many LiIon (LiPo) battery packs can be discharged at 10C or more (that's 10 times the rated current in Amp-Hrs). That sets the minimum cell size to 18650, where my junk cells test at about
1000ma-hr capacity at 1.5A. 14500 would be to small. For charging, the recommended charge rate is 1C. If you plan to do this, make sure you use a LiIon/LiPo/whatever charger. I should mention that cramming 18650 cells into some battery packs is a major project. The good part is that such conversions require fewer cells. You might also consider using prismatic cells such as: Make sure you leave room to let them inflate when charging.Spray a little water into the charger and then measure the AC voltage between an electrical neutral wire and either battery terminal. The life you save may be your own. I stupidly bought 10 of these before I realized what a POS they were. I destroyed them before recycling so that nobody would get hurt.
I measured one of mine. When it got to 4.25V, I stopped to prevent destroying the battery.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
There are a few simple sanity checks for lumen claims. Unfortunately, they have to be done after you've spent the money.
Problem. The spot is not uniform brightness across its diameter. To compensate, I like to measure the hot spot at the center, half way between the center and the edge, and near the edge. I then calculate (or guess) an average lux value.
No integrating sphere or tube required.
If you want to make calculations easy, a 1 square meter circle has a diameter of 1.13 meters (44.5 in). Mark this on the wall and move the flashlight back and forth until the edges of the spot hits the marks. The lux meter will then read directly in lumens.
This measurement becomes difficult when measuring odd shaped spots, such as with bicycle and automotive headlights, but I won't go there.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Even cheapie rechargeable NiMH do that no problem IME, and are less likely to corrode the contacts. There might be some out there that don't, but I think that issue has been exaggerated.
NT
Per Jeff Liebermann:
That one was a keeper: thanks.
Is your reason for using LiIon in flashlights the near-zero self-discharge?
I have been using Eneloops, but not in all of my lights.... yet.
-- Pete Cresswell
No. It's my total disgust with the damage done by leaking alkalines. I discovered something new with the last alkaline battery leak. Even though the battery leaks had made a big mess inside the flashlight, it still lit up normally. So, turning on the light to see if it is still alive is NOT a substitute for visual inspection. Argh.
My main reason for getting into flashlights is that I'm bored and wanted to play with some different toys. I've been reading Candle Power Forums for quite a while and thought flashlights might be fun. The major incentive was a non-monetary bet with a friend over the usefulness of bottom of the line LiIon cells. My contention is that they are economically justifiable, while he demands nothing but the best.
Another reason I won't trust alkalines. They die in the box:
I just remembered that I'm suppose to fix an Apple BlueGoof wireless keyboard. The alkaline batteries leaked and the stainless steel screw on cover, into an aluminum housing, it rotted shut. I've tried brute force, with no effect. Chemical attack comes next.
Same here, but I prefer LiIon. I've been having problems with ordinary NiMH. In addition to self discharge, they don't seem to last through too many charge cycles. Typically, I get about 200 with NiMH and 1200 or more with NiCd. Overall, I do better with NiCd for something that requires regular recharging, such as handheld radios, and flashlights. I'm doing something wrong with NiMH, but haven't figured out what.
Also, LiIon has a much higher maximum discharge current. 20C is common while NiMH is maybe 5C. It's the higher energy density of LiIon that has made power hogs like quadcopters and high power flashlights possible. They could be made to work on NiMH, but performance would suffer. LiIon has also force the introduction of decent battery chargers. One can get away with crude and simple with NiCd and NiMH, but not with LiIon. LiIon requires a well designed charger. Multiple cells charged in series require a balance charger. Many NiCd and NiMH chargers will merrily kill batteries with "quick charge" and various memory effect cures, but even a mediocre LiIon charger will do a reasonable job without killing the cells. Of course, there are plenty of ways to do it wrong, but so far, that's been the exception, not the rule.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Discharging too far is their biggest killer. Or to put it another way, mismatched cells. When one flattens the others push current through it & it suffers badly.
NT
I purchased a 3 pack of the model 350 at Costco. Everyone one of them has this issue. 3 months is about right. Put new batteries in all of them and a few months later they all are virtually drained of battery life.
Matt C
Well, of COURSE! The purpose of selling a flashlight is to sell BATTERIES! If you can design the flashlight to DRAIN the batteries, then you sell more batteries! What a brilliant concept.
Does this thing have an electronic circuit to turn the light on and off? Maybe that circuit has some small current to keep it operating.
Jon
That would be a Duracell Durabeam Ultra 350. The current version sold by Costco is the Durabeam Ultra 380, which is the same flashlight package except all 3 flashlights are black. I would guess(tm) that the 350 was last sold in early 2017, so you probably bought "old stock" that was sitting on the shelf for about 2 years.
A unique feature of these Duracell line of flashlights (350, 380, 500) is that they use FOUR alkaline cells instead of the usual three. This is an attempt to squeeze more lumens out of the flashlight at the expense of battery life. The driver (current regulator) chip used may have been originally designed to run at 3.0 to 4.0v for one LiIon, and maybe 3.9 to 4.8v for three alkaline cells, but might have problems with 5.2 to 6.4v for four alkaline cells. My guess(tm) is that these lights used the usual AMC7135 current regulator IC which is rated at
350ma from 2.7 to 6.0v. In my limited experience tinkering with some of these chips, I found that 6.0v really is the absolute maximum voltage that can be used and that some (not all) chips will blow up at around 7v. Running these on 4 alkaline cells seems a bit close for comfort. Unfortunately, I did not check for leakage current through the driver. It's easy enough to do. Install 4 brand new alkaline cells and measure the current drain when off. If you measure any leakage current, you can guesstimate the standby life of the battery by dividing the capacity of a single cell by this current. For example, if you measured 0.1ma of leakage, all four AAA cells will be depleted in: 750ma-hr / 0.1ma = 7,500 hrs which equals: 7,500hrs / 24 hrs/day = 313 days or about 1 year. Based upon your 3 month experience, and that the package was probably sitting on the shelf for a while, I would guess(tm) you should see about 0.35ma of leakage.However, all is not lost. There are LiIon inserts made to fit in place of alkaline battery holder. This is commonly done with flashlights that take 3 alkaline cells: It can also be done with an 18500 LiIon cell, if you can find one. I've done much the same thing except I used a hard rubber chemistry cork instead of a wine bottle cork. However, I haven't seen anything for doing it with 4 alkaline cells. That's probably a waste of time, so I suggest you recycle the flashlight and buy something that runs on a LiIon cell and not on alkaline cells.
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
Duh. Maybe I should have looked at the data sheet before I continued to guess. See graph on Pg3 "QUIESCENT CURRENT vs. SUPPLY VOLTAGE". The graph only goes to 4.1v which is a subtle hint that 6v might be a bad idea. They could have used two or three AMC7135 chips in parallel to obtain the necessary current handling, but then the leakage current would be 2x or 3x as high. Killing the batteries with this leakage current in 3 months is quite possible.
However, much depends on whether the Duracell Durabeam Ultra 350 uses an AMC7135, and whether power is always applied to the AMC7135. I can't tell from here without disassembling the flashlight, reverse engineering the schematic, and making a few measurements.
Deconstructing a flashlight:
-- Jeff Liebermann jeffl@cruzio.com 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558
...
or use NiMH
NT
I think NiMH is 1.2V while cells are 1.5V.
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.