Disposable e-cig li-ion batteries

[resr]

I got 7 small 3,7V batteries out of a disposable e-cigarettes I salvaged. Are these cells any good&rechargeable? I know bigclive got few to successfully recharge._

 

[Overmind]

Check their voltage to see your actual start point. Then make a capacity test.
They're always good for something.

 

[kc8adu]

i find those same cells in devices that are designed to be recharged.
rather wasteful to use in disposables.
i tell folks all the time to save them as the cells are useful.
top voltage is 4.2v

 

[Lucan]

I have a small collection of e cig batteries similar to what you've pictured. I find these cells perfect for powering cheap led flashlights.

If you couple them with a TP4056 board, you need to change out the resistor that sets the charge current. While tricky, removing and soldering the surface mount resistor is doable by hand. I set the current to 250mA rather than the typical 1A.

Alternatively can add a protection circuit salvaged from a cell phone battery or other protected cell.

 

[resr]

I have a small collection of e cig batteries similar to what you've pictured. I find these cells perfect for powering cheap led flashlights.

If you couple them with a TP4056 board, you need to change out the resistor that sets the charge current. While tricky, removing and soldering the surface mount resistor is doable by hand. I set the current to 250mA rather than the typical 1A.

Alternatively can add a protection circuit salvaged from a cell phone battery or other protected cell.

I have a 1 1/2 Monte Pero coffee jars full of these cells. I need to source some of these SMD resistors first, but it looks like if to keep it 24/7 the charge current will drop down to 200mA quite fast._