The following instructable demonstrates how to make a battery holder for 18650 cells from old laptop battery pack.

To construct it you will require the following:

2 of 3/4" PVC threaded caps

1 of 3/4 PVC pipe 75mm

1 of 18650 battery from old laptop pack or new battery works

1 any battery holder, in this case i used a old 4XAA battery holder

2 screws

2 hex nuts

4 washers

Tools

1 Drill Bit (depending of the screws size)

1 Screwdriver ( depending of screws type)

Step 1: Step1: Drill and Cut the Pipe

1.- Cut pice of 70mm from 3/4 PVC pipe

2.- Drill a hole on the top of 3/4" PVC threaded caps, the hole in the center its ok but not primordial.

3.-Rip off the springs from 4XAA batter holder

Step 2: Step 2: Cap Assembly

1.- Put inside of the cap 1 spring with 1 screw and 1 washer

2.- Repeat the step 1 for all pvc caps.

1.- Put de pvc caps on each side

2.- Take a multimeter and test the voltage.

3.- Now you ready to use on any project