Off Topic: Electrical Question

[XX Case XX]

A lot of companies that make the 18650 rechargeable battery claim very good mAh (like the ones in the photos).

I use the 18650's for several of my flashlights (Fenix/Olight/Nitecore). I want to see for myself what brands of batteries are truthful about mAh and who's lying.

What type of meter would I need to get in order to accurately measure mAh in different 18650 batteries?

____________
Mike. (Photos taken from Internet)

[Railsplitter]

Interesting topic, Mike. I'm curious about your results if you find an accurate way to do this.

[fergusontd]

I believe a regular volt ohm meter set to DC voltage on the 10 volt range should do you. For mAh set it to the lowest amperage setting if possible. I hope tbis helps! ftd

[jerryd6818]

"You can measure a battery's mAh rating using a multimeter, a resistor to act as a load and a stopwatch to measure elapsed time."

A real PITA to do that. I guess I would just use the rating on the label as my yardstick but since you are skeptical about the varasity of the claims........
To check the mAh accurately, you would need to know what size resistor they used in establishing that estimate. Smaller resister (in ohms) more mAh's. Larger resister (in ohms) fewer mAh's. Good luck with that.

[Mumbleypeg]

Here’s what Mr. Google says https://www.ehow.co.uk/how_8637164_meas ... meter.html. Therecarecalsomseveral videos on YouTube about it. All sounds like a PITA to me.

Ken

[jerryd6818]

All sounds like a PITA to me.

Ken

Bingo!! Too much work for too little reward.

[OLDE CUTLER]

Probably has no meaning in the real world, just advertising hype. One never knows if different companies use the same rating system or even tell the truth with the results they find. An example, Craftsman power tools and their horsepower ratings.

[orvet]

If I really need to know the answer to a question like that I asked my little brother. He has a BA in Electronic Engineering Technology and he did the four year degree years with almost a four point average. He missed it by a fraction of a percentage point because he got a B in Differential Equations class. Not sure what that is, but I think is with math. These the family brain trust..
I was the top 10% of the lower one third of my high school class.

[kootenay joe]

There are online Flashlight forums that test and discuss rechargeable batteries in great depth. Those guys are total flashlight geeks just like we are knife geeks. Be careful, it's a rabbit hole you can get lost in for many hours.
kj

[Railsplitter]

Something tells me that Mike is gazing up at us from the bottom of the aforementioned rabbit hole.

[Mumbleypeg]

I’ve had two Streamlights for several years, and two Olights for about a year (my son gave them to me for Father’s Day last year). They are used quite a bit but the original batteries are still working well in all of them.

Mike, what are you doing to your flashlights?

Ken

[FRJ]

Flashlights are amazing anymore. I'm sure everyone knows that by now.

I have several, can't tell you when I had to change batteries. I don't use them everyday.

[XX Case XX]

Mike, what are you doing to your flashlights?

I've been a follower of Streamlight/Surefire since the 80's. I have many of their flashlights and other lighting systems. Lately though, I've been looking into the "new breed" of smaller, more powerful lights from Fenix, Nitecore, and Olight, some of those companies starting out in around 2005 or so.

As I have just begun using flashlights that are powered with the 18650 type batteries, I wanted to find out for myself who makes the better quality units and what companies are being honest about mAh. So far, the Japanese companies seem to be making the higher quality batteries with some even going over the stated mAh.

I guess as with knives, I'm kind of a flashlight geek as well.

____________
Mike

[CamMan21]

I'd agree with using a fixed load, an ammeter and a timer. It'd make for a very simple circuit. You could get fancier and make a circuit that would stop the stopwatch when the voltage drops....then you're not stuck watching it.

I have a bunch of stuff that runs on these batteries. It amazes me that I can get more light from these little batteries than I used to get wearing a lead acid battery on my hip.

[XX Case XX]

It amazes me that I can get more light from these little batteries than I used to get wearing a lead acid battery on my hip.

Ain't that the truth!!

_____________
Mike