Hi guys, i’m new to flashlights and Lithium batteries, so bare with me.
I got few questions,
1. When i get my batteries
”
This”:http://www.fasttech.com/products/1420/10000901/1076400 or this,, (depends of what kind of flaslight i will be getting) and if i don’t have multimeter, how can i know if i need or don’t need to charge them?
2. If i charge them anyway (at once on opening) with Nictore i4 v2 charger, will it shorten their live?
3. Do they need to be fully empty in order to charge them?
4. Do they need to be stored empty/full?
5. Does this batteries lower the output slowly during runtime on max lets say, or just shut down when they are completely empty?
6. Any tips on how to store them as well?
7. Are the Trustrfire’s i linked good? is it worth to pay more for better 26650’s or they are quite good?
So basically, even if you don’t have multimetar, (for now) you can just use your flaslight for random periods of time, - long or even short and when/if the output drops, u just put the batteries in charger, or you don’t even need to wait for output to drop? can i charge them to full capacity even if they are only slightly used for example without shorten live/damage them? thanks in advance!
P.S. The Panasonic batteries i linked, they fit the Nitecore i4 v2? cause i read they are longest from 18650 type batteries.
Just get a digital multi meter. You can get them off ebay for like £7 (or similar depending what country you are in).
While you shouldn’t be scared of li-ion it does no harm to be sensible and treat them with respect.
I personally rarely find the need to run by batteries down, so I normally recharge them when they drop to 3.0-3.10 volts, although I believe it is recommended not to discharge them below 2.75v as it can damage them.
A “protected” ICR should be fine as it’ll shut off when it gets down to this voltage and some flashlights also have low voltage protection, but not all.
Personally I’d stay away from cheap batteries, even for the price I don’t think the represent value for money. Trustfire, Ultrafire or anything else fire is probably best avoided unless you know why you are buying them.
I’ve got some King Kong 26650 INR batteries. They might not be the best ever, but I so far have no complaints with them. 4Sevens also sell a branded 26650, although I don’t know how they stack up in tests, I’d hope they are fairly good though.
But let me explain what happen with my flashlight buying…
I started to look for cheap ~35$ flashlight, (budget limited) after that i decided on SRK original version with LM2 diods (upgraded) CNQG 60$ later on i discovered some 6 diods X6 versions, which where even more expensive, and at the end i decided on BTU Shocker, it was like 65$ over my budget, now the BTU is back to original 120$ price, which make it 85$ over my budget, include 4 x panasonic 18650’s and Nitcore charger and off we go to a whopping 180$, at the moment i really cant afford even a dollar more for multimeter, sadly but it will be on my soon to buy list, thanks one more time.
Again me guys, if i decide to go 26650’s what are the advantages other then runtimes?
Will 2x 18650 have same output as 2x 26650, but lower runtime, i know this sound kinda dumb and that the output- overtime is connected to mah (or its not?) but lets say 2 quality 18650 vs 2x 26650 for 5-10 mins runtime on high in high drain scenario ~ 3500-4000lm? heck even 1x 18650 vs 26650?
Sadly there isn’t a quick or simple answer as it depends on a lot of other factors.
First and foremost it’s worth noting 18650’s are very popular, so the most advanced batteries tend to be these.
That said a batteries performance is not exactly black and white. It’s very easy to get hung up on mAh specs, which while important doesn’t tell the whole story.
Currently the 18650’s can be readily had in 2900, 3100 and 3400mAh (any claims higher than this are likely bogus and cheap cells just don’t perform IMO).
But an important distinction to make is a cells performance under load and how well it sustains voltage. In most 1 battery lights with boost circuits they will only maintain regulation if the battery voltage is similar to the voltage it needs to output.
Here is where it gets interesting, the Sanyo 2600mAh 18650 batteries will as a rule sustain a higher voltage than the 3400mAh Panasonic 18650 batteries.
This means for something like a highly driven (3A) XM-L in a p60 the lower mAh Sanyo is likely to offer longer MAX output than the 3400mAh Panasonic. Either in total running time or as a percentage of what the battery can offer.
Does this mean the 2600 is better?
Well that depends. If instead of using the light on max you tend too use lower modes, firefly or simply have a light that is driven less. Then the larger capacity of the 3400 will offer more total runtime.
With regards to 26650’s, well in reality they are 4000-4400mAh, so not a huge increase over the Panasonic 18650’s. But it is my believe that a good 26650 will offer higher voltage for longer than the 18650’s. Which means longer regulated output on high demanding lights.
In terms of multi battery lights there are two choices.
Series - which means 2 x 3400mAh Panasonics would result in 8.4v and 3400mAh.
Parallel - which means 2 x 3400mAh Panasonics would result in 4.2v and 6800mAh.
In either case on attribute will be superior to a single 26650. But a 2x18650 light will always be bigger than a 1x26650 light.
The Trusfire A8 is a nice 26650 light and apart from a chunkier body isn’t much difference in size to an 18650 p60.
I recently got into Li-Ions as well and http://batteryuniversity.com/ was a great help for me in understanding the fundamentals.
That site has great info on charging and prolonging these cells.
Being a LiIon newb myself I was looking for this specific bit of info, thanks a lot ChD ;)
Does voltage drop in linear fashion with use? Say, I received my keeppower 16650 charged to 3,7V, have been using it about a month, measured just now @ 3.4V. With similiar useage pattern can I expect it to drop another 0.3V in another month, or is there some sort of a exponential curve to discharge? (are these words making sense? :) )
another silly question - can LiIOns be safely recharged (I use a nitecore intellicharger i2) at any state, or is it best to deplete them to a certain level before I pop them in the charger?
Li-Ions do not have any "memory effect" so they can be recharged at any time (even simply topping off). It might have consequences concerning it's life expectancy (not sure), but it is "safe" to do.
Lithium neither like sustained full charge or deep discharge, discharge being the worse case if too low. These are NOT NiXX batteries and do NOT take well to deep discharge. That’s why some of them have protection circuits.
Full charge plus heat increases the internal resistance faster and degrades performance over time. The higher performance the battery, the more this is a problem. With so many ‘qualities’ of LiOn batteries out there (some of them tantamount to junk) there is no blanket statement about longevity that is entirely accurate.
So, If you want to be super picky, keep them above 20% and under 90% charge and cool. This of course is a hassle and needs specialize equipment, so each person needs to determine how important it is and how much effort they want to put in to it. 18650 batteries just aren’t that expensive. Most folks will want a charged light ready to go. Same with laptop batteries.
For storage they like to be around 50% capacity (3.7-3.8v) and in a cool place. I actually keep my RC lipos in zip-locks at storage voltage in the fridge but they are more fragile, more touchy, and higher performance than LiOn. I do store my LiOn at storage voltage if not being used.
