USB Power Banks using AA Batteries

[stevewaters]

I was wondering if anyone has used this or a similar USB Power Bank which takes 4 x AA batteries ? :

https://www.amazon.co.uk/gp/product/B01 ... UTF8&psc=1

- I thought it might be useful as a back-up for charging my GPS, InReach and Phone when there is not the ability to recharge a "traditional" power bank - perhaps in a race with insufficient time to dwell to get it recharged but with shops selling AA batteries.

It costs £5 posted and weighs 36g without the batteries and (using Energizer Ultimate Lithium batteries) I am getting 4.8V and 0.85A. A quick Google looking at tests of these batteries suggests that at that current I could expect to get 3,000mAh from each battery -> 12,000mAh in total.

It seems too good to be true. - Anyone had any experience of these devices ?

[Bearbonesnorm]

I am getting 4.8V and 0.85A.

Is that enough to charge a phone?

[fatbikephil]

I've got a similar one but never used it in anger.... Re the battery capacity my NiMH rechargeable double A's are 2.8 Ah and Lithium ultimates last 3 times as long.....

[stevewaters]

With the batteries in it weighs 133g whereas my 13,000mAh Aker weighs 241g so potentially a good "charge to weight" ratio too.

[slarge]

Don’t always trust the mAh number quoted for AAs. You’ll find that their voltage drops considerably at the end of their capacity which limits their ability to charge. As a quick and easy top up they’ll be good though

[benp1]

It's not just the mAh to worry about, it's the voltage. You want to know how many watts (or watt hours) it has

Most powerbanks run off lithium cells, like an 18650, which means they run at 3.7V-4.2V. An AA cell, alkaline or rechargeable, runs between 1.2V and 1.5V

Unless you're desperate to use AA cells to power your electrickery, you'd be better with a normal powerbank or something like a nitecore F1/F2 that is powered from 18650 cells. An 18650 is worth 3-4 AA batteries

[Shewie]

I used to carry a Powrmonkey charger in the days before smart phones, two AA’s would be enough to charge up my old Nokia brick every week or so, not used it for ages but I don’t think it would charge my iPhone on one set of batts, technology should’ve come along since the though.

[Lazarus]

A quick Google looking at tests of these batteries suggests that at that current I could expect to get 3,000mAh from each battery -> 12,000mAh in total.

It seems too good to be true. - Anyone had any experience of these devices ?

at 4.8 v you would have 3000 mAh at 1.2 volts[most rechargables are this voltage] you have the 12000mAh
the only way to get 12000mAh is if they are 1.2 volt and 12,000mAh[ or use 16 batteries]

[Evesie]

Been using one of these for a year. Seems ok for what I use it for, I'm very much an AA based electrikery economy on trips. Will charge devices at 1A, which works on my phone & top up my AA's for ETrex & lights using any available mains supply or car 12v. Pretty versatile really. Price seems to have popped up a tad tho'
https://uk.gpbatteries.com/products/gp- ... nyway-x411

[dlovett]

I've ordered one off of ebay as the amazon one won't let me buy it. It will come in hand on non dydmao bikes when you can't recharge a power bank.