cell phone battery charger

[vermont]

Hey all,
I tried to make a battery powered (aka powered by AA type batteries) charger to charge my cell phone and it failed miserably.  I can see most chargers on the market get powered by internal batteries that can not get changed out.  I also read the reviews of a couple of the chargers on Amazon and they have the same problems as my home made one (they charge the phone battery to about 17 percent and nothing more and might actually remove power from my phone).
So can someone recommend a charger or tell me what you guys do?
Thanks,

[bmike-vt]

Limefuel

[Biggus Duckus]

I have a RAVPower from Amazon and it works great, gets about 5 full charges on my S5. 16500 mAh I think.

[bakerjw]

I had pretty good luck with a Romoss 10,000 mAh battery block.

That said. When I rode the TD this last June, I have a Shutter Precision PD-8X hub running through a USBWerk feeding the Romoss. The Romoss died. I am not sure that it could handle a series of plug and unplug events that can occur when your speed drops below a certain threshold and the entire system can't provide enough USB power.

In the future, I am going to go with a > 10,000 mAh unit and just charge it every day or so while out riding. My electronics can run a good 3 days without being charged.

[thesonofhans]

I've got a 750lumen Thrunite headlamp with a rechargeable battery.  The device used to charge the battery can also charge usb devices off of the battery.  So I've purchased a few extra rechargeable batteries and it works wonderfully to charge my phone and bike lights.

[offroute]

http://www.monoprice.com/product?p_id=15120

I've used one very similar to this for a many days of riding. Small, light, economical, works as advertised. The only possible down side is that it is not quick to recharge fully.

[Smithhammer]

I've used this one for the last year and it works well. I can get at least 2-3 full iPhone charges out of it when it's topped up. Don't expect much out of the tiny solar panel, though.

https://www.amazon.com/Nexcon-Charger-Rain-resistant-Shockproof-Portable/dp/B00N2D7J5G/ref=sr_1_1?ie=UTF8&qid=1470150990&sr=8-1&keywords=nexcon+charger

[eec]

I've got one of these that works pretty well, and it has a really bright flash light built in:

https://www.amazon.com/gp/product/B017R8VRC2/ref=oh_aui_detailpage_o05_s01?ie=UTF8&psc=1

[AugustWest]

Anker Power Core 10,000 amp hour battery.  I get 3 - 4 iPhone charges out of it.  I can definitely see the utility in being able to buy batteries in town and use those though.  It takes hours to charge this up and if I'm not in a private room it makes it hard to charge.