The C18650 Rechargeable Battery - impressive but varied

[AJMD429]

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The Thermal scope I have uses them, and they seem to have good capacity and rechargeability, so when I was picking up a new flashlight, and it used the C18650 battery, instead of the triple-pack of AAA's or whatever, I figured why not try it.

It's a great flashlight so far - simple bright/dim modes, waterproof more than most (according to the labeling at least), and called the 'Zephyr-R' at 1,500 lumens - made by Police Security Flashlghts.

But I was going to go ahead and plan for the future by buying an extra battery, and I realize there are many different types of C18650, some dubious brands, and there are 'protected' and 'unprotected' ones - so I found this interesting reading on the topic, and thought I'd pass it along...

The Flashlight in question:


https://policesecurity.com/products/zep ... flashlight

The battery type in question:



Article on the batteries - https://commonsensehome.com/18650-battery/

This may be stuff most of you already are familiar with, but the 'protected' versus 'unprotected' thing was new to me for sure...

[lthardman]

Whenever charging any device that uses rechargeable litium batteries, I now use what is called a Count Down Timer. It is a small device that plugs diectly into your A/C outlet. Then you plug your device/charger into the Count Down Timer. The Count Down Timer allows you to choose how long you want the device to charge. From 15 minutes to 8 hours. When the time you have chosen has elapsed, the Count Down Timer turns off the power to the device/charger.

Many devices claim to have overcharge protection circuitry. But, in the fine print, they still say to never leave a lithium ion battery on charge full time. And, they say you should have a 'professional' technician check the device if it has ever been dropped or knocked. That is because that overcharge protection circuitry is pretty delicate. It can easily be damaged without there being any sign of damage externally. And whether the battery is "protected" or "unprotected," damaged overcharge protection circuitry makes that battery unprotected.

I have worked at least a dozen fires caused by run away lithium ion batteries. Those fires burn VERY hot, and are extremely difficult to extinguish. (General Motors advice to fire departments when they respond to an electric vehicle fire involving lithium batteries is to "Let it burn" and protect exposures.)

A good Count Down Timer costs about $10. Given the number of things that run on rechargeable lithium batteries, that is real cheap insurance. Even if you forget you left something charging, the Count Down Timer has your back.