The cheap USB 18650 in the planet???

Batteries and Chargers Chargers
1

Hi guys, I just find this;

https://www.fasttech.com/products/1298405-2013

I think that it is the cheapest USB charger in the planet…

I cant resist…

2

It might be cheap, but I am a bit worried about the safety.

The charger chip is in the USB plug, not in the charger, i.e. if you use another power supply it will be a safety hazard.

I would also expect that it uses a standard LiIon charge chip, i.e. it will do a good charge curve, but probably has to little cooling, extending the charge time.

But it is perfect for use with a hobby charger.

3

Thanks HKJ I am going to order one but I dont have the knowledge and the electronics that you have to make a good test…

4

I got two of them - one is being used a battery holder for a TP4056 module, and I thought I'd play with the other one.

Open Circuit voltage is 4.21 volts

Used a Sanyo 18650 laptop pull discharged to 3.6 volts for testing (still had 2036 mAh capacity).

Not sure of total charging time as I had to stop several times due to interruptions (darn work interfering).

Used USB 2.0 port on Lenova X201

Heath Robinson collection of alligator clips, card insulation etc for measurements, I suspect enough resistance to have some effect on readings.

Started at 3.6 volts and .5 amps then as it got closer to finished I took more readings

4.05 volts .25 amps (10 amp scale)
4.10 volts .22 amps
4.13 volts .18 amps
4.17 volts 97 milliamps (changed to 200 milliamp scale here)
4.21 volts 9 milliamps

And the green LED is on for full

Voltage of cell when fresh from charger is 4.20

Not true CC/CV but certainly looks usable.

EDIT: Replaced the battery for another 40 minutes or so and now need the 20 milliamp range and current is down to 1.9 milliamps.

5

I have seen photos of the usb connector… I dont see any chip inside, just a led and a few components.

So, we get the conclusion that it is not CC CV algorithm?

6

Thanks xv-750 good review

Like he say, not true cc/cv but is usable

7

XV could you please check through the transparent housing with ich components are in it?

Edit : not necessary I have seen picture in the fasttech discussion thread, no IC in it

Have you tried protected batteriess? It is described as 70mm so it should fit…

8

It fits OK and I think thats one of the longest - 69.2mm measured in the carbon fibre jaws of my digital caliper.

9

You would be better with this one or this

10

It isn't a complete charger wihthout a cradle and isn't really suitable to gift to someone with a light even with a cradle, whereas the USB charger could be.

I've been using Miller ML-101's @ $ 4.62 (uses 2 x TP4057's) from Fasttech with gift lights, but this is another alternative.

Miller 101: https://www.fasttech.com/products/0/10001919/1158901-miller-ml-101-mini-usb-smart-charger-for-18650-rec

11

I can understand the motive to save a buck, but you can get a Miller for a couple of bucks more…