I have made a portable lamp out of a normal 230V lamp.
I bought the lamp at Aldi I think.
Then removed the 230V cable and installed a LED pcb, a Lion battery and a charge and driver board.

       

The battery is from an old PC so I do not know the capacity. It are 18650 cells and I  use 3 cells in parallel, so the nominal voltage is 3.7 V (3.0 – 4.2 V).

The old hole for the 230V cord is now the hole for the micro USB charging plug.

For charging the battery and LED lamp driving I use a cheap China board found on eBay. It has a micro USB charging (5V to 3.7 V) and a step up regulator (3.7 V to 12 V) on one board.
On eBay search for “USB 18650 Battery Charger Module Boost Step Up”.
It cost only $ 1.25.

The used light source is a 12 V DC, G4,  2,1 W,  203 lumen, which I bought at jemogfix. I removed the connector and connected it directly  after the diode bridge to save same voltage losses. The G4 is glued to the 230V socket in the lamp by hotmelt.