DIY 18650 battery bank charging

[YonderGod]

I built a battery bank for charging my phone while riding. I used 6 18650 cells from an old laptop in a 3s2p config. Connected to a USB car charger, and it works.

I plan on version 2 having a case of some sort.

But now how should I charge the batteries? I want to make sure I'm not going to blow up my charger. It says it supports Li-Ion, so can I just connect the 2 leads and charge it like that? Or will I need balance leads too?
My charger: http://hitecrcd.com/products/chargers/acdc-chargers/x1-ac-plus-battery-charger/product

 

[Ohbse]

I haven't used that specific charger, but as a rule - yes you should add a balance connector.

The easiest way to do that is order something like a 4s balance extension from hobbyking such as this

Chop off the female end and wire up as many pins as you require, in your case 4 out of the 5. Remove the last pin by pushing on the tab and pulling it out of the connector. This will now plug into any balance charger with the JST XH connectors