# Which flashlight/battery combo is best for long term storage? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [January 8, 2016, 3:23pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500 "2016-01-08T15:23:32Z")\ **Posts on this page:** 18\ **Page:** 1
**Author:** ![Whiskey\_Dickens](https://avatars.discourse-cdn.com/v4/letter/w/9fc348/32.png) [@Whiskey\_Dickens](https://boards.straightdope.com/u/Whiskey_Dickens)\ **Post date:** [January 8, 2016, 3:23pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/1 "2016-01-08T15:23:32Z")
Inspired by [this thread](http://boards.straightdope.com/sdmb/showthread.php?t=780231). I have a “bump in the night” safe, and I’d like to add a flashlight that would last as long as possible without a battery change or charge. My requirements for the light output are pretty modest (this flashlight will most likely only be used indoors while my eyes are adjusted to the dark). The light should be scattered rather than focused. I would like the flashlight to be one-handed. Operated with a button, and maybe the option of an instant-on mode (light illuminates only when the button is depressed). Should I be more focused on the battery rather than the flashlight design? Is there such a thing as a flashlight that doesn’t discharge the batteries during storage? I’ve been using an el-cheapo 9 LED aluminum-body light for this purpose, but it seems to eat batteries just sitting in storage. This is the type of light you’ll see in the impulse buy area of a hardware store. ---
**Author:** ![astro](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@astro](https://boards.straightdope.com/u/astro)\ **Post date:** [January 8, 2016, 4:56pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/2 "2016-01-08T16:56:20Z")
Premium alkaline batteries will usually last a few years in storage the issue is whether you keep them in the flashlight or not. If max run time is your most impt goal a camping LED lantern run off a set of D’s will last days. Frankly your best bet is to get a [premium LED light like this this and](http://www.amazon.com/Fenix-LD22-Edition-LumenTac-Organizer/dp/B00C30LIU6) and keep the batteries out of the flashlight in a separate container until needed. You will have multiple options for run time because the light has variable intensity. This is for scenarios where you need absolute maximum reliability. Having said this another option is to have [multiple cheap lights](http://www.amazon.com/UltraFire%C2%AE-Adjustable-Ultrafire-Waterproof-Flashlight/dp/B015D6L9WI/ref=sr_1_10?s=hi&ie=UTF8&qid=1452272299&sr=1-10&keywords=led+ultrafire) that you keep the batteries in an ready to go. If the batteries let go inside the light you’re only out a few dollars. This is for scenarios requiring immediate light access. I have both types of lights. I’ve had a few (about 25%) of the cheapo LED flashlights die over time due to the electronics randomly dying. The rest keep trucking. ---
**Author:** ![Whiskey\_Dickens](https://avatars.discourse-cdn.com/v4/letter/w/9fc348/32.png) [@Whiskey\_Dickens](https://boards.straightdope.com/u/Whiskey_Dickens)\ **Post date:** [January 8, 2016, 5:11pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/3 "2016-01-08T17:11:17Z")
> [@astro](#): > > Premium alkaline batteries will usually last a few years in storage the issue is whether you keep them in the flashlight or not. Thank you for your response! Aren’t alkaline batteries the standard AAA batteries? I have tried premium and crappy them in my el-cheapo lights and I don’t see 6 months of charge. I’m wondering if this is an issue with the design/construction of the light. > [@astro](#): > > If max run time is your most impt goal a camping LED lantern run off a set of D’s will last days. Frankly your best bet is to get a [premium LED light like this this and](http://www.amazon.com/Fenix-LD22-Edition-LumenTac-Organizer/dp/B00C30LIU6) and keep the batteries out of the flashlight in a separate container until needed. You will have multiple options for run time because the light has variable intensity. Max run time isn’t a factor as these are going in my home defense safe. If I need max run time in a home defense situation, something has gone terribly wrong. For that same reason I was hoping to keep the batteries inside the flashlight and not store separately. I don’t want to be fumbling with them in a stressful situation when time is a factor. ---
**Author:** ![Bone](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bone/32/407_2.png) [@Bone](https://boards.straightdope.com/u/Bone)\ **Post date:** [January 8, 2016, 5:20pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/4 "2016-01-08T17:20:07Z")
CR123 batteries are supposed to have a 10 year shelf life. This was a factor in my choice for my bed light. I still change them probably every other year or once a year depending on usage. If you filter search on that type of battery there are many models to choose from that fit your requirements. I’m a fan of Fenix lights but there are lots of good ones out there. My EDC light is a four sevens that runs on a single CR123. ---
**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:** [January 8, 2016, 5:27pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/5 "2016-01-08T17:27:10Z")
For an emergency use only light I’d be looking for an LED unit using CR123 cells. They are primary cells, not rechargeable, with a many year storage life. They don’t work too well in really bright lights because they can’t supply power fast enough, but that’s not an issue in a 200-300 lumen light. You also want a light with a momentary on, called a clicky, and a tail switch. A side switch is harder to activate because the switch might be on the bottom when you pick it up. A tail switch is always in the same place. ---
**Author:** ![Claverhouse](https://avatars.discourse-cdn.com/v4/letter/c/13edae/32.png) [@Claverhouse](https://boards.straightdope.com/u/Claverhouse)\ **Post date:** [January 8, 2016, 5:57pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/6 "2016-01-08T17:57:11Z")
[**Michael Bluejay’s Battery Guide**](http://michaelbluejay.com/batteries/). ---
**Author:** ![Whiskey\_Dickens](https://avatars.discourse-cdn.com/v4/letter/w/9fc348/32.png) [@Whiskey\_Dickens](https://boards.straightdope.com/u/Whiskey_Dickens)\ **Post date:** [January 8, 2016, 6:27pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/7 "2016-01-08T18:27:29Z")
Thank you **Bone** and **GaryM** for your advice regarding the CR123 style of battery. I will look for compatible lights and the batteries! Thank you **Claverhouse** for the battery comparison sheet. It confirms what the other posters are recommending regarding the shelf life. ---
**Author:** ![bump](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@bump](https://boards.straightdope.com/u/bump)\ **Post date:** [January 8, 2016, 6:37pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/8 "2016-01-08T18:37:09Z")
I’d look into something that uses regular AA batteries, and then get the lithium variants (Energizer Ultimate Lithium) for example. Same shelf life as the CR123 batteries, easier to find and more versatile overall. The main advantage of the CR123 batteries is the higher voltage, which lets manufacturers crank more light out of their flashlights, and you’re saying you don’t need that. You’re ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [January 8, 2016, 6:48pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/9 "2016-01-08T18:48:28Z")
I got myself a hand-crank flashlight with a supercapacitor in place of a battery. You have to crank it to get it to light up, but you can store it forever. And unlike a hand-crank flashlight with a rechargeable battery, you never have a problem with the battery draining or becoming unchargeable. I replaced the storage batteries with supercapacitors in my other hand-crank flashlights, too. If you want a battery that can be stored forever and then used, you want a molten-salt battery. But AFAIK, nobody makes Molten Salt Battery Flashlights > **[Molten-salt battery](https://en.wikipedia.org/wiki/Molten_salt_battery)** > > Molten-salt batteries are a class of battery that uses molten salts as an electrolyte and offers both a high energy density and a high power density. Traditional non-rechargeable thermal batteries can be stored in their solid state at room temperature for long periods of time before being activated by heating. Rechargeable liquid-metal batteries are used for industrial power backup, special electric vehicles and for grid energy storage, to balance out intermittent renewable power sources such as ... ---
**Author:** ![Bone](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bone/32/407_2.png) [@Bone](https://boards.straightdope.com/u/Bone)\ **Post date:** [January 8, 2016, 7:14pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/10 "2016-01-08T19:14:05Z")
> [@bump](#): > > The main advantage of the CR123 batteries is the higher voltage, which lets manufacturers crank more light out of their flashlights, and you’re saying you don’t need that. One of the requirements for this type of flashlight is that it blind or disorient a target. Long throw and a tight beam that is very bright are positive qualities. IMO AA powered lights don’t fit this well enough. ---
**Author:** ![Whiskey\_Dickens](https://avatars.discourse-cdn.com/v4/letter/w/9fc348/32.png) [@Whiskey\_Dickens](https://boards.straightdope.com/u/Whiskey_Dickens)\ **Post date:** [January 8, 2016, 7:31pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/11 "2016-01-08T19:31:02Z")
> [@bump](#): > > The main advantage of the CR123 batteries is the higher voltage, which lets manufacturers crank more light out of their flashlights, and you’re saying you don’t need that. Yessir, not 100% sure I need a face-melting light, I won’t rule out AA batteries per your suggestion. ---
**Author:** ![bump](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@bump](https://boards.straightdope.com/u/bump)\ **Post date:** [January 8, 2016, 7:37pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/12 "2016-01-08T19:37:27Z")
> [@Bone](#): > > One of the requirements for this type of flashlight is that it blind or disorient a target. Long throw and a tight beam that is very bright are positive qualities. IMO AA powered lights don’t fit this well enough. Not according to the OP, though. ---
**Author:** ![Whiskey\_Dickens](https://avatars.discourse-cdn.com/v4/letter/w/9fc348/32.png) [@Whiskey\_Dickens](https://boards.straightdope.com/u/Whiskey_Dickens)\ **Post date:** [January 8, 2016, 7:41pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/13 "2016-01-08T19:41:55Z")
> [@Bone](#): > > One of the requirements for this type of flashlight is that it blind or disorient a target. Long throw and a tight beam that is very bright are positive qualities. IMO AA powered lights don’t fit this well enough. I suppose this gets more into philosophy of use, but I wasn’t planning on using the light as a weapon. Just in conjunction with one. Maybe the prevailing school of thought is otherwise and I just need my ignorance fought. ---
**Author:** ![Bone](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bone/32/407_2.png) [@Bone](https://boards.straightdope.com/u/Bone)\ **Post date:** [January 8, 2016, 7:50pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/14 "2016-01-08T19:50:55Z")
> [@bump](#): > > Not according to the OP, though. Bump in the night safe is to be used with a weapon. That type of use typically wants brighter, more disorienting power. He says it is to be used with a weapon. A blinded target is better than a non-blinded target IMO. It doesn’t take a ton of output to do this. 200-300 lumens in a tight beam will do it. CR123s are a good fit for this. ---
**Author:** ![Telemark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/telemark/32/372_2.png) [@Telemark](https://boards.straightdope.com/u/Telemark)\ **Post date:** [January 8, 2016, 7:55pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/15 "2016-01-08T19:55:46Z")
> [@bump](#): > > I’d look into something that uses regular AA batteries, and then get the lithium variants (Energizer Ultimate Lithium) for example. Same shelf life as the CR123 batteries, easier to find and more versatile overall. Agreed. I have several AAA headlamps that hang in the hallway and they last for years, are plenty bright, and very versatile. Don’t outthink yourself; regular AA or AAA alkaline or lithium batteries are good for 8-10 years. If your cheap flashlights are draining them, just leave them out of the flashlight. ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [January 8, 2016, 8:42pm UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/16 "2016-01-08T20:42:58Z")
Another way to make sure you batteries are good when you need them. Often the reason a flashlight is dead is that it got turned on accidentally (like in the glove compartment or trunk or boat cabin or backpack) without you knowing it. And I suppose these days, flashlights that use a switch to activate a circuit might have a low level drain even when “off” (though I doubt it). If you put half the batteries in backwards, ain’t much draining going to be happening no matter what you do switch wise. This only really works with lights that use even battery pairs. Then you gotta REMEMBER that you put half of them in backwards. But that is what I did with lights for use in the great outdoors on a regular basis. And if it was an emergency light, used the lithiums as well. If you go online to one of those major battery suppliers, you can probably also find lithiums that are designed more for long life rather than lightest weight or cheapest costs per power or maximum capacity. ---
**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:** [January 9, 2016, 12:09am UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/17 "2016-01-09T00:09:40Z")
Some lights, and I have two, use a tiny blinking LED as a locator beacon. My Tiny Monster light has that feature. I use the light daily and the cells are recharged regularly. My other light with the locator beacon is seldom used and I’ve found the beacon drains the battery. Not good at all. ---
**Author:** ![JKilez](https://avatars.discourse-cdn.com/v4/letter/j/e5b9ba/32.png) [@JKilez](https://boards.straightdope.com/u/JKilez)\ **Post date:** [January 9, 2016, 2:56am UTC](https://boards.straightdope.com/t/which-flashlight-battery-combo-is-best-for-long-term-storage/742500/18 "2016-01-09T02:56:04Z")
> [@Bone](#): > > Bump in the night safe is to be used with a weapon. That type of use typically wants brighter, more disorienting power. He says it is to be used with a weapon. A blinded target is better than a non-blinded target IMO. It doesn’t take a ton of output to do this. 200-300 lumens in a tight beam will do it. CR123s are a good fit for this. > [@Telemark](#): > > Agreed. I have several AAA headlamps that hang in the hallway and they last for years, are plenty bright, and very versatile. Don’t outthink yourself; regular AA or AAA alkaline or lithium batteries are good for 8-10 years. If your cheap flashlights are draining them, just leave them out of the flashlight. You can easily find Cree-based flashlights that are over 300 lumens, yet take standard AA, AAA, or 18650 batteries. I had been looking for a solution to this type of problem as well. The consensus I have seen for the requirements of: 1) bright bulb, 2) infrequent use, and 3) long-term storage, is standard lithium batteries (like the Energizer Ultimate Lithium). They will be both brighter and last longer than LSD lithium rechargeables or standard alkalines. If you do not need long-term storage, or the flashlight is used regularly, then the 3.7V 18650 Li-ion batteries provide the best power source.