What Rechargeable Power Bank Should I Get?

I know this questions has been asked before, but I also know that things change quickly some times, thus I am posting now. My family and I will be doing some traveling soon and I am looking into possibly buying an additional backup power bank. I have one now that is quite small and another that is think and roughly the size of a smartphone. What is the best way to select a power bank? Is assume that the bigger the device the more capacity it has. My wife will want a small one and I am not opposed to getting one a bit bigger. Should I get one with a sealed pack? Are there ones that allow a person to insert 18650, or other size, batteries? What would be the pros and cons of one vs. the other?

Anker is the go to model, for a turnkey approach. Lots of users out there and while you can't swap out cells, you're basically renting a good unit for 3+ years, or whatever you end up getting out of it.

I have a Ruinovo 4x18650 PB, which is a bit older, but I can swap the batteries out. I got that on FastTech for $34 shipped, with four Sanyo 2600mAh FMs. My 2A charge input has stopped, but that could be the crappy cable I bought on Ebay, but the 1A works still. Aluminum case, indicator lights, 1A and 2.1A Apple coded USB ports.

I also bought the Xiaomi Mi 10,000mAh jobbie, but that uses 3 fixed 18650 and getting them out will be destructive, so that's a rental. Yields 6250mAh in useable power, which is a key which I'll touch on later. This was about $14 + $3 (silicon sleeve) shipped from FastTech. Only has a single USB port, but it's Apple coded and 2.1+ amps.

http://www.mi.com/en/pb10000/

Finally, I have a Tomo V8-4 (Soshine clone) which opens easily for cell swap. 2 2.1A ports, Apple coded, nice LED display with current display for both ports. Cheap plastic, but about $16 shipped from Tomo.

http://www.tomopowerbank.com/

I do have a Fujitsu 4xAA PB and NiMH charger, but NiMH for power banks ain't such a hot idea, since nominal voltage is 1.2v and boosting to 5.0vdc is inefficient.

Getting back to the li-ion power banks, remember, 18650s are 3.6v/3.7v nominal, so you loose some juice boosting up to 5.xx volts. As Xiaomi truthfully states on my Mi, you have 10,000mAh, but only 6250mAh usable, so figure whatever you get, if things are truthful, you might be getting only 66% into your personal devices.

Good luck, Chris

Speaking of power banks. When are we going to see the ones with quick charge tech or higher than 2.1A that is user replaceable cells?

Some features to look for: A pack that can charge 2 amps from ALL of its ports, cheaper packs will only give you 2 or 3 amps total, so whatever's plugged into the second port only gets a slow charge. My current pick, the Anker Powercore 2, not only charges full speed to all three of its ports simultaneously, but it has two input ports, so you can charge the pack itself twice as fast. Get a phone-specific battery case for the wife.

MarioJP said:

Speaking of power banks. When are we going to see the ones with quick charge tech or higher than 2.1A that is user replaceable cells?

Click to expand...

Some will do 2.4A, but I doubt any of the manufactures are going to approach 3A-4A with 3.7v lithium-ion base cells. I guess if you need fast charge, you use your car socket, 120vac, or slum it like the rest of us.

Chris

My personal choice is Anker PowerCore+ 26800 mAh:

My personal choice is Anker PowerCore+ 26800 mAh:



And in theory you may replace cells:

How are those 8 cells wired like that to be able to safely monitor each individual cell?

Later in the video (3:39) he shows the bottom of the pack, which reveals the balance leads, see below.