Mercury | Emergency USB Power Bank

When fitted with good quality alkaline AA batteries, this will charge a phone slowly - it's better to turn off the phone as the output from this charger is only 800mAh so charging is slow. It's unlikely to be able to fully charge a phone due to the power delivery characteristics of single use alkaline batteries, but it topped up my phone by about 20% a few times before the batteries died. Using single use Lithium batteries will probably work better, or perhaps using rechargable NiMH. This is not a replacement for a charger or a power bank, but makes an excellent emergency charger as AA batteries are readily available everywhere. It won't charge my camera as it doesn't deliver enough power.

This product is a great idea - power/charge USB devices from AA batteries. Great for emergencies when you're more likely to find a shop selling AA batteries than a fully charged USB power bank. Unfortunately it looks like this device isn't that well designed. If it's given anything other than totally brand new batteries from the pack it'll refuse to even turn on, never mind charge anything (I've used Energizer and Varta). That means it won't do much charging before it rejects a set of brand new batteries, meaning you'll be chucking out batteries that still have plenty of life in them. I've not tried it with rechargeables but if you have charged AA batteries ready when you can't charge from the mains, you might as well carry a large USB power pack with you instead!

Works well, but ... I've found mine runs down to 16% and if you go below that it comes back to 16 (Duracells). Haven't tried to run it empty yet.

Great wee product for Emergency charging if your out walking ! However , I bought the best quality batteries I could buy and it only charged my iPhone once ( to 72%) before batteries went flat ! Handy though !

The best emergency power bank possible in my personal opinion when it comes to design, quality, size and price. I have actually purchased quite a few of these for my friends and family with packs of AA batteries as an emergency power banks for a potetial longer blackout. If paired with rechargable batteries depending on their mAh capacity this will charge your average smarphone more than once.

I have lots of rechargeable AA batteries for many different devices. More and more devices have built in lithium batteries and charge through USB. I put 4 AA rechargeable batteries in this case and it becomes a power bank. Great idea that works well!

All I can say is that it's not worth it

I like this small and solid, unfortunately it does not support low current flow and switches off after a few seconds, however I found that holding the switch in keeps the current flowing, therefore using an elastic band to keep the button in allowed me to charge very low current devices such as my hearing aid charger, the rechargeable batteries I am using have lasted for 2 weeks so far without requiring recharge, based on charging for about 3 hours a night, I do not think they would last long trying to recharge a phone battery.

A l'usage ce produit est d'un intérêt limité : la charge s'arrête trop rapidement avant d'avoir utilisé toute la capacité des piles installées. Pour piles classiques uniquement car inutilisable avec des batteries AA rechargeables même de qualité.