Biggest batteries I've found to fit in the stock XRT battery tray
Traxxas 2820X - 2200mAh 7.4V 2-Cell 25C LiPo Battery - Hub Hobby
A Guide to Traxxas' Batteries and Chargers — Roger's Hobby Center
Traxxas EZ-Peak Live 4S Completer Pack Multi-Chemistry Battery
EZ-Peak Live 12-amp NiMH/LiPo Fast Charger with iD® Auto Battery
Engineers Week, Traxxas iD System
TRAXXAS Charging Cable - for RC hobby batteries — Batteries America
traxxas battery guide Traxxas, Save, Projects to try
Hobbypark RC Battery Y Harness Series Connector
5000mah 11.1v 3-Cell 25C LiPo Battery
How to charge RC batteries
Traxxas Battery Guide, Traxxas RC Battery
NOTE: Traxxas VXL Brushless models are 3S/2S LiPo compatible; XL-5 Brushed models are only 2S LiPo compatible! Keep this in mind when choosing a
Traxxas 3S Power Cell 25C LiPo Battery w/iD Traxxas Connector (11.1V/6400mAh)
Traxxas EZ-Peak Plus Charger & 2x 5000mAh 3S LiPos E-Maxx Brushless
Part number 2890x. Part number: 2890x. (2) Traxxas Power Cell LiPo 4-Cell 6700mAh Battery with iD connector. BATTERY SPECIFICATIONS: 4S - 14.8 Volts
2 Traxxas 2890X Power Cell LiPo 14.8V 6700mAh Batteries w/ID X-MAXX 8s UDR MAXX