I currently charge my phone (out in the field) with the Nitecore F1 charger/powerbank. I use it mostly as a powerbank and I feed it 18650 Fenix cells (3500 mAh), of which I always carry with me 2 or 3. Lately, my demands on the phone have increased and I am at a point where the capacity of 2 of those batteries isn't enough to get me through the day(s). I do not always have the 3rd 18650 battery with me, and when I do it is meant to be saved for something else. So, basically I need to add some power to my "power bundle" (it really is a bundle of all sorts of stuff). I sometimes use the F1 to charge other batteries, with the help of my Olight magnetic charger. Also, I can actually power up the F1 with four AA batteries (in series, a DIY rig) and charge the depleted 18650 batteries, plus my 14500 cells. As you can see, simply going for a dedicated PowerBank is not good idea for me, so, please, do not recommend any of those. My setup is very versatile and I can get power for my tech in all sorts of ways. At this time, I'm only looking to add a little more power to my kit. Instead of buying another Fenix 18650 (which would barely get me to where I need to be, if that), I figured I may as well get a 26650 cell instead. Since I've never owned one before, I feel that I should ask for advice. I apologize that this isn't (directly) flashlight-related.
My priorities are in this order:
1. Safety: The battery doesn't catch fire when in use or in storage.
2. Reliability: The battery doesn't just die on me for no reason.
3. Capacity: I need to get something that justifies the additional heft, when compared to a 18650/3500mAh cell.
4. Price is last: Not looking to save any money and I'll pay what I have to.
I have never bought an unprotected lithium cell. I do own a few unprotected 18650's but those were included with all sorts of tech I bought over the years. I almost never use them and I NEVER take them with me into the field.
The F1 charger (in the PowerBank mode) will shut down when the battery reaches 2.8 volts (it says so in the manual), so, I do not worry about damaging my new, unprotected 26650 cell that way, HOWEVER: another concern of mine is a short circuit scenario! What happens when water gets to an unprotected IMR battery? Does it catch fire and light up my whole backpack, to leave me stranded miles and miles from civilization, WITHOUT survival gear? (Just one example of water getting onto the battery: a leaky water bottle in the backpack, enough said). This has always been my no.1 concern with regards to all electronics that I carry with me into the wilderness.
So, after careful consideration, this is where I am right now:
www.fasttech.com
The rated capacity is OK and the tested capacity is even better. They even provide a little Excel chart, which looks pretty sweet. TBH, after shopping around, I don't think that you can beat those specs in the "protected realm". However, there is one (and only) review by someone who claims that the tested capacity of this battery is 3890 mAh... Hmm...
I should also say that I am not planning to use my new 26650 battery for anything other than to charge my phone with (and possibly other tech too).
I measured the output of the F1 charger (in the powerbank mode), w. my Fenix 18650 in place. When charging my phone it is: ~5V, ~850mA. I figure that F1 draws right around 1A from the battery and bumps up the output voltage to 5V (USB specs), from the nominal 3.6V (or whatever) of the cell. As the 18650 approaches depletion, the current drops, obviously. Actually, I have not tested where things are at towards the end. I don't think that my Fenix's will allow themselves to be drained all the way down to 2.8 volts (at which point, even the F1 will shut itself off). Also, my phone stops charging itself once the input current drops below 200mA... hmm.. .. So, thinking about it, I don't really know whether all this time I've been fully utilizing my protected 18650 batteries. Does anyone know by any chance at which point the undervoltage protection kicks in with those babies?
At any rate, with the setup I have right now, the nominal charging current is right where I want it to be. At home I charge EVERYTHING at 500mA but in the field I need to be charging my phone a little faster than that, for as long as the power source can provide, anyway.
Sheesh!... over 800 words!... damn.
Any suggestions? Thanks!
My priorities are in this order:
1. Safety: The battery doesn't catch fire when in use or in storage.
2. Reliability: The battery doesn't just die on me for no reason.
3. Capacity: I need to get something that justifies the additional heft, when compared to a 18650/3500mAh cell.
4. Price is last: Not looking to save any money and I'll pay what I have to.
I have never bought an unprotected lithium cell. I do own a few unprotected 18650's but those were included with all sorts of tech I bought over the years. I almost never use them and I NEVER take them with me into the field.
The F1 charger (in the PowerBank mode) will shut down when the battery reaches 2.8 volts (it says so in the manual), so, I do not worry about damaging my new, unprotected 26650 cell that way, HOWEVER: another concern of mine is a short circuit scenario! What happens when water gets to an unprotected IMR battery? Does it catch fire and light up my whole backpack, to leave me stranded miles and miles from civilization, WITHOUT survival gear? (Just one example of water getting onto the battery: a leaky water bottle in the backpack, enough said). This has always been my no.1 concern with regards to all electronics that I carry with me into the wilderness.
So, after careful consideration, this is where I am right now:
$19.29 LC 26650 3.7V 5000mAh Rechargeable Li-ion Battery - test capacity 5753.2mAh / protected at FastTech - Free Shipping
Probably the best deal for a LC 26650 3.7V 5000mAh Rechargeable Li-ion Battery test capacity 5753.2mAh / protected USD 19.29 as of 7/29/2022 - Free shipping worldwide on all orders. Prices unbelievably cheap.
www.fasttech.com
The rated capacity is OK and the tested capacity is even better. They even provide a little Excel chart, which looks pretty sweet. TBH, after shopping around, I don't think that you can beat those specs in the "protected realm". However, there is one (and only) review by someone who claims that the tested capacity of this battery is 3890 mAh... Hmm...
I should also say that I am not planning to use my new 26650 battery for anything other than to charge my phone with (and possibly other tech too).
I measured the output of the F1 charger (in the powerbank mode), w. my Fenix 18650 in place. When charging my phone it is: ~5V, ~850mA. I figure that F1 draws right around 1A from the battery and bumps up the output voltage to 5V (USB specs), from the nominal 3.6V (or whatever) of the cell. As the 18650 approaches depletion, the current drops, obviously. Actually, I have not tested where things are at towards the end. I don't think that my Fenix's will allow themselves to be drained all the way down to 2.8 volts (at which point, even the F1 will shut itself off). Also, my phone stops charging itself once the input current drops below 200mA... hmm.. .. So, thinking about it, I don't really know whether all this time I've been fully utilizing my protected 18650 batteries. Does anyone know by any chance at which point the undervoltage protection kicks in with those babies?
At any rate, with the setup I have right now, the nominal charging current is right where I want it to be. At home I charge EVERYTHING at 500mA but in the field I need to be charging my phone a little faster than that, for as long as the power source can provide, anyway.
Sheesh!... over 800 words!... damn.
Any suggestions? Thanks!
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