# Why does every LED flashlight I use flicker and dim so much? **URL:** \ **Category:** Factual Questions\ **Created:** [December 19, 2017, 5:43am UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842 "2017-12-19T05:43:40Z")\ **Posts on this page:** 19\ **Page:** 3
**Author:** ![Channing\_Idaho\_Banks](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/channing_idaho_banks/32/250_2.png) [@Channing\_Idaho\_Banks](https://boards.straightdope.com/u/Channing_Idaho_Banks)\ **Post date:** [December 20, 2017, 9:46am UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/41 "2017-12-20T09:46:44Z")
you could you could do a lot worse than a jetbeam AA flashlight. I have been carrying this light for the entire year, it works great. ttps://www.gearbest.com/led-flashlights/pp\_368125.html ---
**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\ **Post date:** [December 20, 2017, 10:17am UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/42 "2017-12-20T10:17:54Z")
> [@ZonexandScout](#): > > (ahem…) > > Why is anyone banging on his/her flashlight? There’s nothing wrong that’s likely to be helped by banging on it. Change the batteries, clean the contacts, tighten the bulb (if it’s an incandescent with a removable bulb), but don’t just bang on it. If there’s an intermittent connection that momentarily reconnects when you bang on it, you need to get another flashlight. It will just fail you again when you most need it. > > Posted on Behalf of Flashlight Bangers Anonymous Because, at least with the (admittedly cheap) lights I have, it works. Sure, after I’m finished with it, I may then open the batter compartment to try and fix contacts or whatever. (pulling the spring is a good one, I find.) But, when I’m in the middle of using it, I just need the light to work again. I also misplace them often, so I don’t have much of a desire to buy something expensive. If I had something where I needed a flashlight regularly, then I’d probably get one that’s decent. But I don’t. And, while I try to just put everything back all the time, I inevitably have failed to do so when I actually need it. ---
**Author:** ![Face\_Intentionally\_Left\_Blank](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/face_intentionally_left_blank/32/288_2.png) [@Face\_Intentionally\_Left\_Blank](https://boards.straightdope.com/u/Face_Intentionally_Left_Blank)\ **Post date:** [December 20, 2017, 12:49pm UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/43 "2017-12-20T12:49:18Z")
> [@BigT](#): > > Because, at least with the (admittedly cheap) lights I have, it works. Sure, after I’m finished with it, I may then open the batter compartment to try and fix contacts or whatever. (pulling the spring is a good one, I find.) But, when I’m in the middle of using it, I just need the light to work again. People suggest cleaning the contacts. I think it’s seldom any fault of the contacts. I keep my flashlights in a kitchen drawer, not in a salt-water tackle box on a fishing trawler. It’s simply NEVER been the contacts in my experience, at least not in the way that a cleaning/polish would fix anyway. I’ve used very fine metal sandpaper to shine the contacts, I’ve wiped with alcohol to help remove any substance that might cause a problem. Doesn’t help. As I pointed out above, the same basic battery-holding scheme is often used for small electronic devices, and I’ve NEVER had to clean those contacts. You’d think electronics would be far more sensitive to momentary voltage drops. ---
**Author:** ![Fridgemagnet](https://avatars.discourse-cdn.com/v4/letter/f/22d042/32.png) [@Fridgemagnet](https://boards.straightdope.com/u/Fridgemagnet)\ **Post date:** [December 20, 2017, 1:56pm UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/44 "2017-12-20T13:56:54Z")
> [@jz78817](#): > > one other thing to consider is that LEDs will typically draw far less current from the battery for a given amount of light. if you have a tiny bit of corrosion on any electrical contacts, it may cause flickering and dimness due to poor contact whereas the higher current of an incandescent bulb might “break through” the corrosion/oxidation. This is the correct explanation for the OP’s issue. It’s a “wetting current” thing. In an ideal world the battery contacts would be clean and free from oxidation so they would always make good contact. In the real world there’s invariably a bit of dirt, oil and oxidation and often this crud forms a thin insulating layer between the contacts. Two conditions are required to overcome this insulating layer: a voltage high enough to punch through the insulation, and a current high enough to form micro-welds that act as conductive bridges through the insulation. Cheap LED torches can be problematic with their switching as they’re often just an LED in series with a current limiting resistor, and if the running current isn’t enough to overcome the contact wetting current then the contact will be dodgy (you can tell if you’ve got such a cheap LED torch as the light will dim noticeably as the battery drains). Nicer LED torches have a little chip that regulates the current - this is designed to give a constant light output as the battery voltage fades (within limits), but also has the bonus of reducing battery contact issues as the decoupling capacitor across the chip momentarily produces a high current surge as it charges up, thus overcoming the wetting current requirement of the contacts. The wetting current phenomenon is a big headache when trying to switch low currents. The usual approach is to use gold flashed contacts - as used in nice signal relays, nice hi-fi connectors, and credit card chip contacts - but this isn’t practical for batteries as (aside from the cost) gold is soft and easily eroded and is no good for high currents as it’s soft, has relatively high resistivity, and tends to melt from resistive heating. Talking of credit card contacts: there’s a trick where huffing on a credit card will get the thing to work on a stubborn reader that initially refuses to recognise it, especially if the gold flashing on the card or reader contacts is a bit worn away. This works because the moisture from your breath effectively lowers the flashover voltage that’s needed to breach the insulating dirt layer. > [@am477494](#): > > Many times i’ve Resolved similar problems by spraying WD40 and cleaning out the battery contacts. YMMV By rights WD40 should make things worse, but in practice it does seem to improve bad contacts. Dedicated switch cleaner aerosols are the ideal thing to use, but I’d say WD40 works almost as well. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [December 20, 2017, 2:54pm UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/45 "2017-12-20T14:54:50Z")
> [@Face\_Intentionally\_Left\_Blank](#): > > People suggest cleaning the contacts. Yet you say banging on it helps. Battery contacts are about the only thing that might be helped by banging the device, by moving the battery within and causing it to scrape against the contacts. ---
**Author:** ![mr\_horsepower](https://avatars.discourse-cdn.com/v4/letter/m/eb8c5e/32.png) [@mr\_horsepower](https://boards.straightdope.com/u/mr_horsepower)\ **Post date:** [December 20, 2017, 5:04pm UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/46 "2017-12-20T17:04:53Z")
there’s no shortage of people that can geek out over flashlights for sure. I’ve got some friends that show me their latest tactical flashlights all the time, know all the specs, are members on flashlight websites, etc… funny thing is, every single one of those friends of mine could just as easily use the flashlight on their cell phone for all they need a flashlight for. i can’t say how much that small sample size represents the ‘flashlight community’, but I’d hazard a guess fairly well. i just need flashlights that work. every day. even if abused. if any of you had the need for a cordless drill, cordless 1/4" impact, cordless 1/2" impact, sawzall, etc… then your choice of flashlights would be so much simpler. my dewalt 20v flashlights take the same battery as my electric impact that i use to remove lug nuts on my car/ trucks. given that i can rotate the wheels/ tires on two vehicles and still have charge in the battery, it’s no surprise that my flashlights will illuminate for hours & hours & hours. (it seems i read 18 or 20 hours or something, I’ve never actually needed to know) after that you just pop the battery in the charger for a little while. dewalt also has a 12v series in these lights that are awesome. their batteries fit a full range of other tools also. look on amazon. multiple hundreds of reviews, nary a bad one in the bunch. > **[DEWALT 12V MAX LED Work Light, Hand Held (DCL510) , Yellow - Basic Handheld...](https://www.amazon.com/DEWALT-DCL510-12-Volt-Max-Worklight/dp/B0043XX8AO)** > > The DCL510 12V MAX\* LED Worklight has a bright LED light and a powerful magnet. Kick stand of LED rechargeable work lights allows for hands-free use in multiple placements. Head rotates 360 degrees and pivots. don’t take this as a dewalt ad either, plenty of other decent brands of tools out there. i can tell you to 100% get your dewalt tools and batteries from dewalt or at least an xrp retailer. home depot sells a lot of consumer grade, non professional grade stuff that looks similar but isn’t in a lot of cases. the biggest thing to look for is “xrp”. that doesn’t apply to flashlights but does their other tools & also their batteries. ---
**Author:** ![crowmanyclouds](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crowmanyclouds/32/19884_2.png) [@crowmanyclouds](https://boards.straightdope.com/u/crowmanyclouds)\ **Post date:** [December 20, 2017, 6:25pm UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/47 "2017-12-20T18:25:22Z")
> [@Face\_Intentionally\_Left\_Blank](#): > > People suggest cleaning the contacts. I think it’s seldom any fault of the contacts. {…} Depends on the flashlight. My [Arc-AAA](https://www.google.com/search?newwindow=1&tbm=isch&q=arc+flashlight&backchip=online_chips:original&chips=q:arc+flashlight,g_2:aaa&sa=X&ved=0ahUKEwj-0ZKWmpnYAhUEU98KHVf_DiEQ3VYIJigA&biw=1067&bih=449&dpr=1.5) started to not turn on, but would if I removed and replaced the head. Eventually, I cleaned the threads, worked just like new. Raw aluminum to aluminum thread joints require some TLC. CMC fnord! ---
**Author:** ![YamatoTwinkie](https://avatars.discourse-cdn.com/v4/letter/y/cc9497/32.png) [@YamatoTwinkie](https://boards.straightdope.com/u/YamatoTwinkie)\ **Post date:** [December 20, 2017, 8:36pm UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/48 "2017-12-20T20:36:04Z")
> [@Stranger\_On\_A\_Train](#): > > You can find SureFire G2 or comparable polymer bodied flashlights on sale online for $60 to $70, and they’ll last for years of service in all kinds of conditions. > Stranger I was also going to recommend the Surefire G2x, looks like its currently selling for about $41 on amazon, which may meet the OP’s criteria. ---
**Author:** ![gigi](https://avatars.discourse-cdn.com/v4/letter/g/a587f6/32.png) [@gigi](https://boards.straightdope.com/u/gigi)\ **Post date:** [December 20, 2017, 10:45pm UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/49 "2017-12-20T22:45:16Z")
> [@mr\_horsepower](#): > > dewalt also has a 12v series in these lights that are awesome. their batteries fit a full range of other tools also. look on amazon. multiple hundreds of reviews, nary a bad one in the bunch. > > [https://www.amazon.com/DEWALT-DCL510-12-Volt-Max-Worklight/dp/B0043XX8AO](https://www.amazon.com/DEWALT-DCL510-12-Volt-Max-Worklight/dp/B0043XX8AO) Sweet, they also have one that takes the 20V pack. I got the cordless wet/dry vac last year that takes the 20V rechargeables. > **[DEWALT 20V MAX LED Work Light, Magnetic, Freestanding and Clip-On, Bare Tool...](https://www.amazon.com/DEWALT-DCL044-Hand-Held-Light/dp/B01KAG1818)** > > DEWALT 20V MAX LED Work Light, Magnetic, Freestanding and Clip-On, Bare Tool Only (DCL044) - Amazon.com ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [December 21, 2017, 12:43am UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/50 "2017-12-21T00:43:52Z")
> [@Face\_Intentionally\_Left\_Blank](#): > > But flashlights essentially use the same battery-retaining mechanism that any handheld battery device does. If this is the case, wouldn’t calculators and handheld video games suddenly fritz out and need turned off/on? Surely they would be more sensitive to dropped power than even an LED. if they rely on digital logic, then there’s a very good chance they have one or more voltage regulators supplying the ICs which can tolerate tiny “blips” in the power supply. edit: the other thing is that a lot of these flashlights have aluminum bodies, and sometimes have a dissimilar metal touching the aluminum body to complete a circuit. Aluminum is a very reactive metal which forms a thin layer of oxide on its surface shortly after exposure to air; banging on a dim/flickering flashlight can “break through” this oxide layer and improve the electrical contact. ---
**Author:** ![Face\_Intentionally\_Left\_Blank](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/face_intentionally_left_blank/32/288_2.png) [@Face\_Intentionally\_Left\_Blank](https://boards.straightdope.com/u/Face_Intentionally_Left_Blank)\ **Post date:** [December 21, 2017, 1:43am UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/51 "2017-12-21T01:43:09Z")
Well, I’m learning a few things, so while it’s taking longer than we thought, it’s still progress. First: I grew up when alkaline batteries were just coming out and were pretty hot shit. I remember having to explain to my parents how the old style “heavy duty” batteries were just sad, and very often would not power new electronic devices straight from the package. Guess I got stuck in that mindset, and figured if I got good alkalines, I should be fine. I have to start using the fancy rechargeables and lithium one-use batteries, and start to look on alkalines as the zinc-carbon batteries of today. Second: It seems, according to a few of the fine folks of The Dope, there’s an issue with clean contacts and corrosion. Dissimilar metals in the construction may cause this. Am I reading it right where the low LED draw doesn’t overcome the resistance of the mildly corroded contacts? Seems odd though, because the same LED lights drain 3 Alkaline batteries fairly quickly. Why aren’t they electroplating the contacts in gold now, to prevent this issue, if they know it’s a problem? It’s not that expensive - even $2 1/8" patchcords have pretty gold tips these days. ---
**Author:** ![Fubaya](https://avatars.discourse-cdn.com/v4/letter/f/c2a13f/32.png) [@Fubaya](https://boards.straightdope.com/u/Fubaya)\ **Post date:** [December 21, 2017, 3:47am UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/52 "2017-12-21T03:47:34Z")
> [@GusNSpot](#): > > Two of mine are the same, Olight M20 X WARRIOR. Has 3 brightness levels. Off/on brings it up in the last brightness you were using. Totally different switch for strobe. I am smart nuff to do my own SOS signal, if I am so bad I can’t do it or I am in a place or condition that it is a moot point, it won’t bring help in time. > > I leave it on ‘medium’ and if that is not what I want, I go up. So, one setting, ‘on & off’ works just like you say you want. > > YLMV 😃🆒😉 I really don’t want extra modes but the ones that have a separate button are ok. I have a couple that use a half press of the on/off button to cycle through modes. A full press counts too, on a random basis. So if it’s on high and you turn it off, when you turn it sometimes it’s on high, sometimes it’s flashing an SOS or is dim and you think the batteries are dead or something. Those are in a drawer where they’ll never be used unless I lose my good flashlights. ---
**Author:** ![GaryM](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/garym/32/241_2.png) [@GaryM](https://boards.straightdope.com/u/GaryM)\ **Post date:** [December 21, 2017, 4:21am UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/53 "2017-12-21T04:21:14Z")
Several of my Nitecore lights have gold plated contact areas. One in particular with the gold uses four 18650 cells in parallel and can draw 9 amps on turbo mode. GaryM ---
**Author:** ![mr\_horsepower](https://avatars.discourse-cdn.com/v4/letter/m/eb8c5e/32.png) [@mr\_horsepower](https://boards.straightdope.com/u/mr_horsepower)\ **Post date:** [December 21, 2017, 5:32am UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/54 "2017-12-21T05:32:36Z")
> [@gigi](#): > > Sweet, they also have one that takes the 20V pack. I got the cordless wet/dry vac last year that takes the 20V rechargeables. > > [https://www.amazon.com/DEWALT-DCL044-Hand-Held-Light/dp/B01KAG1818/ref=sr\_1\_2?s=hi&ie=UTF8&qid=1513809767&sr=1-2&keywords=dewalt+20v+worklight](https://www.amazon.com/DEWALT-DCL044-Hand-Held-Light/dp/B01KAG1818/ref=sr_1_2?s=hi&ie=UTF8&qid=1513809767&sr=1-2&keywords=dewalt+20v+worklight) yeah, the 20 volt ones are all i have. i just mentioned it (the 12 volt one) as i figured some of the people here might find it, and some of the 12 volt tools that share the same battery, to be something more inline with what they could see having for use around the house. ---
**Author:** ![Face\_Intentionally\_Left\_Blank](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/face_intentionally_left_blank/32/288_2.png) [@Face\_Intentionally\_Left\_Blank](https://boards.straightdope.com/u/Face_Intentionally_Left_Blank)\ **Post date:** [December 21, 2017, 5:54am UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/55 "2017-12-21T05:54:14Z")
> [@mr\_horsepower](#): > > yeah, the 20 volt ones are all i have. > > i just mentioned it (the 12 volt one) as i figured some of the people here might find it, and some of the 12 volt tools that share the same battery, to be something more inline with what they could see having for use around the house. My brother-in-law has one of those for his 18-volt set, I think. Man, they turn night into day. A LITTLE big to carry in my pocket, though 🙂 Giving thought to this one, for $40 shipped with code “2017XMAS”. Has everything included - a battery (though probably not a great one) and I can charge it using a USB charger. Don’t have to buy a separate battery and charger to add to the startup costs. > **[Neutron 2C V3](https://www.thrunite.com/neutron-2c-v3/)** > > THRUNITE’s high quality LED flashlights are not just bright - they’re tough as nails and designed to be practical for a wide variety of users. Learn more about their variety of product lines and find the perfect gear for your needs right here at the... Might buy another,better battery later if that’s an issue, but this will get me into a _somewhat_ reasonably-priced, decent LED light. $40 flashlights. Sheesh. ---
**Author:** ![gigi](https://avatars.discourse-cdn.com/v4/letter/g/a587f6/32.png) [@gigi](https://boards.straightdope.com/u/gigi)\ **Post date:** [December 21, 2017, 4:25pm UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/56 "2017-12-21T16:25:04Z")
> [@Face\_Intentionally\_Left\_Blank](#): > > My brother-in-law has one of those for his 18-volt set, I think. Man, they turn night into day. A LITTLE big to carry in my pocket, though 🙂 🙂 I mostly only keep one in the car in case of an emergency on the road, so a big light will be just fine. I had a big spotlight like this [https://www.northerntool.com/shop/tools/product\_200670683\_200670683?cm\_mmc=Google-pla&utm\_source=Google\_PLA&utm\_medium=Lighting%20\>%20Spotlights&utm\_campaign=Wagan%20Tech&utm\_content=56181&gclid=EAIaIQobChMI2IuD9cGb2AIVR57ACh1t4wXZEAQYAiABEgKlfvD\_BwE](https://www.northerntool.com/shop/tools/product_200670683_200670683?cm_mmc=Google-pla&utm_source=Google_PLA&utm_medium=Lighting%20%3E%20Spotlights&utm_campaign=Wagan%20Tech&utm_content=56181&gclid=EAIaIQobChMI2IuD9cGb2AIVR57ACh1t4wXZEAQYAiABEgKlfvD_BwE) but it gave out just sitting in the trunk over time. ---
**Author:** ![mr\_horsepower](https://avatars.discourse-cdn.com/v4/letter/m/eb8c5e/32.png) [@mr\_horsepower](https://boards.straightdope.com/u/mr_horsepower)\ **Post date:** [December 21, 2017, 9:34pm UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/57 "2017-12-21T21:34:32Z")
> [@Face\_Intentionally\_Left\_Blank](#): > > My brother-in-law has one of those for his 18-volt set, I think. Man, they turn night into day. A LITTLE big to carry in my pocket, though 🙂 > > Giving thought to this one, for $40 shipped with code “2017XMAS”. Has everything included - a battery (though probably not a great one) and I can charge it using a USB charger. Don’t have to buy a separate battery and charger to add to the startup costs. > > [Neutron 2C V3 - ThruNite Official Store](http://www.thrunite.com/thrunite-neutron-2c-v3-1100-lumen-flashlight/) > > Might buy another,better battery later if that’s an issue, but this will get me into a _somewhat_ reasonably-priced, decent LED light. > > $40 flashlights. Sheesh. yep. having the batteries already makes the choice much easier. having to depend on them to work every time is still the biggest driver for me. $40 can seem high or not, it’s all in how much you rely on it. hell, i paid $40 for ten #2 Phillips head bits the other day off the snap on truck. (those little throw away bits you put in the end of a magnetic screwdriver or drill driver bit holder). i didn’t like it, but they are good bits & don’t round off near as easy as the cheap ones. ---
**Author:** ![Face\_Intentionally\_Left\_Blank](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/face_intentionally_left_blank/32/288_2.png) [@Face\_Intentionally\_Left\_Blank](https://boards.straightdope.com/u/Face_Intentionally_Left_Blank)\ **Post date:** [December 21, 2017, 10:50pm UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/58 "2017-12-21T22:50:03Z")
> [@mr\_horsepower](#): > > yep. having the batteries already makes the choice much easier. > having to depend on them to work every time is still the biggest driver for me. > > $40 can seem high or not, it’s all in how much you rely on it. > > hell, i paid $40 for ten #2 Phillips head bits the other day off the snap on truck. (those little throw away bits you put in the end of a magnetic screwdriver or drill driver bit holder). i didn’t like it, but they are good bits & don’t round off near as easy as the cheap ones. Yeah, expectations. Ppl expect to pay a premium for high-quality tools, especially from Snap-On, and when they use them every day. My expectation for a flashlight is something I buy at Wal-Mart. I picked up an Astrolux S1 for under $20 (18350 battery), and got an extension tube so I could use the bigger 18650 battery. Picked up 2 18350’s and an 18650, and a universal-type charger I saw advertised on SlickDeals last night. Seemed bright, I can use a big OR small battery with it, so I can carry it in my pocket easily or set it up for longer use. Also picked up a cheaper flashlight while I was at it: > **[Q5 240Lumens 3Modes Outdooors Bicycle EDC LED Flashlight 18650/AAA](https://www.banggood.com/Q5-240Lumens-3Modes-Outdooors-Bicycle-EDC-LED-Flashlight-18650-or-AAA-p-958659.html?akmClientCountry=America&rmmds=myorder&cur_warehouse=CN)** > > Only US$6.18, buy best q5 240lumens 3modes outdooors bicycle edc led flashlight 18650/aaa sale online store at wholesale price. Also uses the 18650, and can use 3 “AAA” batteries as well in a pinch. Don’t expect much from the latter, but it will be an interesting experiment to see if the better batteries make a cheaper flashlight work without all the dimming/flickering. ---
**Author:** ![Clothes](https://avatars.discourse-cdn.com/v4/letter/c/b5e925/32.png) [@Clothes](https://boards.straightdope.com/u/Clothes)\ **Post date:** [December 22, 2017, 12:07am UTC](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842/59 "2017-12-22T00:07:13Z")
Flashlights top my list of Things that Don’t Work. The D-cell was invented in 1896. The first flashlight that used D-cells came out in 1899. What you can buy today for cheap - the D-cell powered flashlight - has changed very little since then. Now you can get ones that use an LED and only one D-cell instead of two. Be ready to shake and bang on those as well. A flashlight ought to be cheap. It’s just a flashlight! People mean well when they tell you to spend 20 or 50 or 90 dollars or more for some product with a name like “UberMax XXX Vindicator”. But what you are basically paying for is improved connectivity between power source and light-producing thing, be it wee incandescent bulb or something sexier. What the common cheap flashlight has is a spring that pushes the anode (nubby end) of the battery up against the contact at the bottom of the bulb, which is screwed into or otherwise held in touch with a flared metal base, and there’s a piece of bent copper or something that’s supposed to move up and complete a circuit when you… oh hell, you already know this, and you can probably see why this arrangement can go wrong so easily. Bad connection = flickery or dim light = rampant dissatisfaction. What is called for is a redesign of the plain-vanilla hand torch that can be banged out inexpensively but fixes the chronic poor-contact issues that users have hated since the 19th century. Has to use standard D or AA or AAA cells, because that’s what’s available. But has toothed spring clips or some such that can really get a grip on things, that won’t be flummoxed by a little bit of corrosion. (This principle should also be adopted by any product that depends on the usual spring-loaded battery holder - TV remotes and such - that like to fail because they use a poor design that should have been discarded ages ago.) [Previous page](https://boards.straightdope.com/t/why-does-every-led-flashlight-i-use-flicker-and-dim-so-much/804842.md?page=2)