i have 3 of these chargers now no problem they just take a while for the last .01v balance and discharge slowly
http://www.amazon.com/iMax-LiPo-Bala...s=rcjuice+imax and this power supply
http://www.amazon.com/RCJuice-Power-...s=rcjuice+imax and never had a problem with these batteries
http://www.amazon.com/Venom-5000mAh-...gy+hardcase+2s though i prefer these im not sure if they fit the slash you may need to measure
http://www.hobbyking.com/hobbyking/s...arehouse_.html you will have to solder on connectors though and if you get that charger you also need this
http://www.amazon.com/RCJuice-Traxxa...ywords=rcjuice and these will need to be soldered to the batteries if you get the turnigy ones
http://www.amazon.com/Traxxas-3080-C...traxxas+female ive heard good things about these smc batteries but have no personal experience with them
http://www.smc-racing.net/index.php?...ory&path=67_97