Got Lumens?
Flashlight Enthusiast
Don't Let THIS
Happen to Your Flashlight
Alkaline Battery Warning
Hi folks,
Sorry for interrupting your day, but I wanted to issue this PSA: Alkaline batteries should
not be used with your Foursevens flashlights.
Alkalines are designed for low-power applications like TV remotes. The strain on the
battery causes it to release gas that will corrode the interior of the battery tube, leading
to the buildup of a thick black layer of oxidation, and ultimately the failure of the light.
This problem is made worse by the high power demand of the Foursevens lights, the raw
metal surface, and the sealed environment (compared to your TV remote).
Sorry for interrupting your day, but I wanted to issue this PSA: Alkaline batteries should
not be used with your Foursevens flashlights.
Alkalines are designed for low-power applications like TV remotes. The strain on the
battery causes it to release gas that will corrode the interior of the battery tube, leading
to the buildup of a thick black layer of oxidation, and ultimately the failure of the light.
This problem is made worse by the high power demand of the Foursevens lights, the raw
metal surface, and the sealed environment (compared to your TV remote).
How the problem was discovered:
I received a number of non-operational lights that suffered from this problem to varying
degrees.
I previously encountered this issue with the Prometheus Lights Beta QR over a year ago,
so I knew right away what I was looking at – Alkaline batteries venting under stress.
Some users also reported an audible "pop" from the pressure buildup when opening the
head after prolonged use.
The problem is more pronounced if you run the light frequently and at full power. By the
same token, if you don't use your light frequently and/or at low power, you probably
don't have an issue. If you use Lithium disposable or rechargeable NiMh batteries (as
recommended) the venting and subsequent corrosion will not occur.
Steps you can take:
I received a number of non-operational lights that suffered from this problem to varying
degrees.
I previously encountered this issue with the Prometheus Lights Beta QR over a year ago,
so I knew right away what I was looking at – Alkaline batteries venting under stress.
Some users also reported an audible "pop" from the pressure buildup when opening the
head after prolonged use.
The problem is more pronounced if you run the light frequently and at full power. By the
same token, if you don't use your light frequently and/or at low power, you probably
don't have an issue. If you use Lithium disposable or rechargeable NiMh batteries (as
recommended) the venting and subsequent corrosion will not occur.
Steps you can take:
[*=left]Stop using Alkaline batteries
If you don't like wasting money, you should look for
some brand name Nickel Metal Hydride (NiMh) batteries online or at your local
hardware store. We're currently running a 30%dealonthisbattery&chargerbundle.
If you feel the need to purchase batteries you have to throw in the trash, I
recommend Lithium disposable.
Please note, you may NOT use lithium-ion rechargeable batteries.
[*=left]Check the inside of your battery tube for corrosion. It takes quite a bit to cause
the light to fail; a small amount of corrosion is tolerable. If your light works, please
keep using it, just change your batteries. At this time it is not clear if the corrosion
will stop progressing, or continue to grow when the corrosive agent
(Alkaline battery) is removed from the light.
[*=left]If your light is black inside and no longer works, please email me at [email protected]
to make arrangements.
Thanks for your support and sorry about any inconvenience this might have caused.
Jason
Exploding Flashlights:
What You need to know
We recorded a short episode of "I'm No Expert" in response to a handful of reports (some recent)
of 2-cell lithium flashlights exploding. One instance in November resulted in a fatality – the user
had his flashlight in his mouth while working under the hood of his car.
(For the record: these were NOT Prometheus Lights or Foursevens flashlights.) In the interest of
safety, we put together this PSA to help you all understand what is likely causing this to happen
and, most importantly, how to prevent it. Any 2-cell lithium light has the potential to pose the
same danger. Be informed.
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