18650 getting tired ?

Each night I take “billie” my BTU Shocker for a work out and walk along a totally unlit path about 2 miles long.
I was using in this protected AW cells about 5 years old, I was very surprised at how short the run times have been, I noticed a distinct difference between high and turbo mode, but there seems not much difference now, even when cells are freshly charged.
My question is do the cells get weaker as they are used more/get older, should I stop being a tight git and invest in some more new ones, I’m not too concerned about cost if I do, but what are the ultimate ones to get.
Frankly after getting my Shocker I prefer my SRK, way bright enough for my uses, and a hell of a lot easier in the hand.
Any advice would be most appreciated, thanks

Age is the probable degradation of performance. Li-ions have a finite life span of about 500-1000 charges, and over the five years, do you think you have reached those numbers?

This causes an increase in internal resistance, making the cell sag under a high load and the voltage drops, which is probably why you’re having little difference between turbo and high modes.

Good quality 18650’s aren’t too expensive these days, so you might want to grab a couple Panasonics, LG’s, Sanyo’s or Samsung cells. FastTech seems to have a decent selection with a good price.


Realistically they likely have exceeded 500 charges, soon crops up doesn’t it!!
I will crow bar my wallet open and order some new ones, next week, if I have any money left over after taxing my cossie!!
Thanks for advice, I recently bought some SenyBor cells and these seem great, compared with my AW, but will do as you say and get some decent ones, once again thanks for help,

No problem, good 18650’s are about $10-15 a pair, so they shouldn’t break your bank. :slight_smile:

Good 1865’s for $10 to $15……?
Not that I can find, assuming we are talking about respectable capacity say over 2400mAh or better 3400/3600mAh.
You need capacity for a long walk on full power!
Recharging is APITA so lets do it as infrequently as possible.
BTW is it wise to buy the protected versions or do most flashlights now have a low voltage cut out that does the same thing?
Finally my cheapo chargers have occasionally overcharged my batteries so now I find it a safer practice to check the voltage every half hour. As I said its APITA!!
So what charger(s) are reliable & suitable & what do these typically cost?

The Panasonic Protected 3400s are too long for most of my flashlights and my wife’s e-ciggy, so you might want to start with 3100s like these:

Panasonic Protected NCR18650A Rechargeable 3100mAh 3.7V 18650 Lithium Batteries

I have some Eagletac 3100s I paid $15 a piece for, and I believe they are the same re-branded Panasonics above for about half that price!

For a cheap charger I like the Nitecore i4.

What we recommend for 2600mAh (best performance to price ratio) is the Sanyo: https://www.fasttech.com/products/0/10001901/1143802

For higher capacity ones Panny 3100mAh or 3400mAh: https://www.fasttech.com/products/0/10001980/1141103 or https://www.fasttech.com/products/0/10001980/1141104

Although some lights have low voltage cut off, it’s not a bad idea of use protected batteries anyways.

The chargers I would recommend are the Intellicharger series, the i2 and the i4. They aren’t too expensive, and they’re pretty good for how they perform. I think Wallbuys.com offers the best prices for them.


Racer beat me to it. After all, he’s a racer! :stuck_out_tongue: