MYOG USB power bank

4000 mAh nitecore batteries weigh 1.7 ounces.  You would need 3.25 batteries to equal the Anker, so total weight would be 6.25 ounces

Cool little board.

Another option would be 2 Vapcell P2160B for 2 x 6000mAh, with built in charge controller and port removing the need for an external board.  2*78g = 5.5 oz, a bit shy of your 13000mAh target.  Without knowing the efficiencies, hard to say how it really compares to the Anker.

Drawback to any multi Vapcell approach is having to recharge multiple cells (babysitting), no PD or QC protocols, and they’re not as reliable as Anker.

The reliability risk has me sticking with Anker

I obsess about reducing my battery consumption, it’s the best way to save battery weight.

I like that better.  No need for separate electronics.  If the electronics failed on 1 unit, you have the second unit.

Yeah, I think I’ll just use the Anker.  Maybe, I’ll bring my new unit on a 5 day hike.

This discussion triggered an impulse buy of two 4000mAh Vapcells for ~ $31Can from Ali.  1.8oz each

https://www.vapcelltech.com/h-pd-200.html

One of these will cover me a 4-5 day trip, maybe longer, we’ll see how they do!

Picked up some silicone protective sleeves for $3 each.  Hacking away at them will probably take them down to ~ 0.1 oz

do you use the same USB C connector to charge it and discharge it?

what is the lowest current that it will charge?  For a device that requires 20 mA of USB voltage, the Anker keeps turning off

I’ve been using the XTAR PB2S.  It accepts two of the larger 21700 cells or in a pinch, 2 18650’s.

I’ve been purchasing 5000mAh batteries for mine from IMR Battery.  I like the flexibility.  For a short weekend trip, maybe I just need the bank with 2 21700 cells.  For a longer trip, I can add 2 or 4 additional 21700 cells if I’m expecting to use my phone for a lot.  (And my Pixel 6a’s battery isn’t as good as it used to be.)

David D – the VapCell 6000’s are intriguing.  I have read that you should most definitely carry those in a protective case (like most Li-ion cells).  Despite having the look and feel of a standalone charger, letting one bounce around loose seems like a bad idea.

I like the idea that when the 21700 batteries start to lose their “oomph”, I can toss the cells and get new ones while I keep reusing the PB2S.

that looks like a really nice charger/powerbank

3 ounces is a bit heavy for gram counters.  If you add 3.25 of those 4000 mah batteries, just to compare to my 13000 mAh Anker, that would be 8.5 ounces.  The Anker weighs 8.5 ounces.  But the xtar would allow you to take just as many batteries as you need which would be a big advantage.

Based on the Vapcell page I linked, it looks like the Vapcell’s charge/discharge with the same cable.

I’m curious to see if it’ll work with usb connector adapters, I use https://rollingsquare.com/products/incharge-6 plus a Garmin connector adapter for the watch

Some two way usb charge ports (e.g. Garmin Messenger) don’t support connector adapters for the discharge direction (needing normal cable), probably because they don’t support the USB charge sense resistor specs.  Cheap enough to experiment with

Jeff, see these protective cases, this is what I was referring to that may be able to be cut down to ~ 0.1 oz.  I ordered 4 to play around with, dirt cheap

https://www.aliexpress.com/item/1005001941708702.html

I went with 18650 option instead of 21700, I was looking for the lightest possible solution to charge my phone one time 75%. That usually takes me to ~ 5 days

You could make a bag with 3D mesh, then put that in a gear bag.  I use a gallon ziploc bag for miscellaneous gear.

Same here, a gallon Ziploc is my ditty including electronics and other odds and ends.  I carry another as a sink, and the ditty gives me a back up

Nitecore has at least one cell similar to Vapcell P2160B, if the nitecore name has a better reputation to some.  I have one and am testing it to see how reliable it is.

Nitecore used to make a 18650 charger/power bank, the F1.  It also fit unprotected 21700 cells.  I have one, and it works great, allowing one to take as many cells as needed for the trip.   With a single 18650, it weighed 3.09oz.  They can still be found online

Maglight makes one too, as does Acebeam

The Vapcell seems to have the highest capacity/weight.

Some good test results.  And the PCB is potted which is promising for reliability

Nice find Jerry. I can see that being useful.

Concerning the Vapcell, where does one use a 3.6v battery? Or is there a voltage stepdown circuit?

On the vapcell battery, if you plug into that usb plug, it’s usb voltage, ~5V

So only the USB plug is higher voltage? I can use them to replace the standard AA 1.5v batteries? That makes sense.

Terran: 3.6 volts at the terminals, 5v at the USB plug. You can use it in a 3.6 volt device (there are many), but not in a 1.5v device.

A few devices (like some flashlights) can use either 1.5v or 3.6v. They are not common, but I have seen more of them in the past year than previously.

and, the vapcells are 18650 sized which is larger than AA.  18650 won’t fit into your AA device

Okay. I think I had a camera that used those. An odd size, at least here. I was confusing them with AA’s.

Terran Terran – there is also the CR132A, which is about the same diameter as a AA battery but half the length.  Early on I had a Princeton Tec headlamp that used two CR123’s.   I grew to really dislike that headlamp because those batteries were expensive and it was impossible to see whether the batteries were on the brink of dying or still had a decent amount of life left in them.

Some steripens use CR123 batteries – ” I grew to really dislike that headlamp because those batteries were expensive and it was impossible to see whether the batteries were on the brink of dying or still had a decent amount of life left in them.” – same here

I like devices with usb rechargeable battery – I charge up before a trip

With the steripen, occasionally I thought the batteries were good but got only one treatment before it died.  I tried rechargeable cr123s but I only got a couple treatments before they died.

I bought I set of 4 AAA rechargeable lithium-ion batteries similar to the ones in Terran Terran’s second video.   I tried using them in a Black Diamond SPOT headlamp in cold weather and they did not do well.  After about 30 minutes of use, the headlamp started flashing, indicating the batteries were running low, and these were freshly charged.  I’ve never seen my Sanyo Eneloop NiMH rechargeable batteries perform as poorly.  Maybe the Lithium Ion AA’s do better in warmer weather.

I keep Sanyo Eneloop AA and AAA batteries around the house for just about everything from remote controls to handheld FRS “walkie talkie” radios.

I use eneloop AA NiMH batteries in cold weather without problem.  20F

After many years they started pooping out in cold weather so I got some new ones.

I think some lithium batteries do better in cold, some worse.  My phone complains when it gets below 32F.  Which isn’t a problem because I put it in my pocket

CR123a come in lithium, the most cold resistant readily available battery (by a long shot).  My winter headlamp takes 2 of them or one 18650 rechargeable.

Next most cold resistant is lithium ion (different than lithium which isn’t rechargeable), followed by NiMh.  Alkalines freeze.

Nitecore, Molicell and Fenix made cold resistant LiI but they were taken off the market.  My guess is RoHS, same as NiCDs which were also cold tolerant.