The battery junction link I posted was for the batteries that Jesso (vaprlife) recommends using in the Joker. Below is another link for batteries and charger combo.
BatteryJunction
By particular type, I didn't know if you were looking for regular protected Li-on batteries or the high drain batteries. I'm no expert so I won't try to explain. I would go with the batteries Jesso suggested. I use 3V Tenergy LiFePO4s in my Joker, but plan on getting the ones I linked above.