Congratulations on winning your first Pleo! It will be a great experience for sure. As far as the batteries go, like others have stated, just the one adapter will work fine the one that comes with your Pleo, If you get more batteries, just keep charging them, There is one important thing to know about the Ucube Egg charger and battery. Some people I am sure do not remember to read the instructions that are on the side of the box, this is what they say, word for word: do not immerse the battery in water, ( duhl)do not reverse the battery position,+ and - negative, terminals, do not dispose the battery in fire or heat,(

do not short circuit the battery, do not transport or store the battery together with METAL ITEMS SUCH AS HAIRPINS, NECKLACES, ETC. do not strike or throw the battery against hard surface
do not directly solder the battery and pierce the battery with a nail or other sharp object.
what they do not mention on the box but on the Battery itself and some people may not read is the following:" there are many factors that will affect the efficiency and life of the battery, including
the play way of electron pet and the charging custom. Please follow the below instructions to operate the battery.THE CHARGING TIME OF BATTERY DO NOT OVER EIGHT HOURSE. Completely charge discharge.
what this means is that it is very important to not leave battery in charger over eight hours. If the battery has completely charged, ( 3 hrs,) do not just think you can leave it in and take it out when ready.This can damage or shorten the life of the battery. Take it out when it is done charging and if you charge it before you go to bed, make sure you take it out as soon as you get up. Also completely discharge the battery when using it, If you stop playing with Pleo, leave battery in, do not take out and charge again, it should stay in till Pleo slows down and will curl up and want to go to sleep, If you don't let the battery completely discharge, it will also shorten the life of the battery. If you have three Li Polymer batteries, charge one and put in pleo, then begin charging the next, and repeat process and you should never run out of Pleo Playtime, You will slow down before Pleo does,

Remember though, that the green batteries that come with Pleo, can not be used in the egg charger, and the Li Polymer batteries do not fit in or can be used in the green c charger that come with Pleo, Also the egg charger batteries do not turn green, they flash red while charging and turn solid red when done.
RedwoodsMama and Family Nova