Home made batteries

I'm going to build my own battery.
Using Panasonic NCR18650B's
Found this test tube holder
https://www.indigo.com/lab_supplies/test_tube_racks/33770-plastic-test-tube-rack.html#.Vldox19OLKD
18mm holes. Want to use 8, 4 as is but inverted onto the batteries, and 4 cut down to fit and be epoxied to the 1st 4.
Note that the "bottom" is a smaller hole. Hoping it's exactly the size of the + terminal.
Please pick this idea apart. I will not get offended.

Mainly say that for ebike purposes NCR18650B is not a recommended cell, because its weak discharge rate capability, Can be used with an acceptable performance for continuous discharge under 1.5C.

About that holders, are not the ones for battery building, it will make the battery really huge as I see.

How are you going to build it? iron soldering or spot welding?

Those holders are an example of the right ones to work with

http://www.aliexpress.com/store/product/18650-battery-holder-bracket-Cylindrical-battery-holder-18650-li-ion-cell-holder-Flameresistant-material-Safety-anti/623665_1982118662.html