3000mAh Mini Portable Charger for $6


#1

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#2

Just out of curiosity, do you ever hear about these things catching fire? They do have low-cost Li-ion cells in them.


#3

Six bucks is a good price for a rechargeable fire-starter, too.


#4

This is a very good price. All my other external chargers are Anker products - I’ve had great luck with them. However, I lost my mini, pink one and for this price I’ll try a random brand. Ordered.


#6

I had one short out and nearly catch fire. it’s the cheap 18650 batteries.

Then, when I put it back into my pocket to show my friends, it shorted and burnt a hole through my jeans and boxers. I have the scar to prove it.

Just make sure you don’t mess around with it (admittedly, I had taken mine apart to see the circuits, no jiggery pokery for me next time)


#7

I just yesterday in fact took one of these apart, and fixed my rechargeable electric beard trimmer - the crappy old AAA NiMh batteries inside were totally dead, and the shaver didn’t function at all. Soldering only 2 wires, a bit of hot glue, and voila - a mad max beard trimmer, with the motor exposed. classy :slight_smile:


#8

You could run it from a Li-ion cell salvaged from a dead laptop battery. Usually only one of the three pairs of cells is kaput, which gives you four fairly good cells for free. All you need to attach is a protection circuit, which can be salvaged from a dead cellphone battery if its current rating is good enough for the motor. Then just add a module of a battery charger, I have good experiences with the uber-cheap TP4056-based ones, and you have a fully functional device.

Beware of the modules, though - they come with both miniUSB and microUSB connectors. For compatibility with cellphone chargers, opt for the microUSB ones. You can replace the connector with ease, as the circuitboards support both, but it’s annoying.

The charger gives up to one amp of charging current, which can be adjusted by replacing one of the resistors on the board. It can feed the attached electronics too; I tested it with a cheapo Canon camera, as a replacement of a vendor’s overpriced charger.

I don’t have such scar, but I managed to short a lead-acid battery I used for that purpose some decade and half ago. Made a lot of smoke and stripped insulation from a length of wire. I learned my lesson and added a Polyswitch reversible fuse to the battery.

Polyswitch fuses are small, cheap, full of little problems and disadvantages, and very very useful as protective devices. If the application can live with their warts, use them.

Don’t let a little mishap stop you. The lesson is not “don’t poke inside”, it’s “take care while poking inside”.


#9

My mobile provider has been giving similar looking portable chargers away for free - http://ee.co.uk/ee-and-me/out-and-about/ee-power


#10

w = a * v

Why do advertisers keep advertising the A, but not the V or the W? Seriously, 3000mah could be virtually anything if neither total wattage, or mAh at what voltage is specified.


#11

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