I did not, batteries from Antigravity are Lithium Polymer LIPO3 and not Lithium Ion. LIPO batteries can still have issues similar to Lithium Ion but are much more rugged. All of the Lithium horror stories you here about are pretty much all from Lithium Ion. Plus the fact that the Automotove line that Antigravity uses have an integral controller to manage the batteries and shut them down if needed. The really nice feature of this (they call it "Restart") is that when your battery gets low from a parasitic drain (sitting for a while, left the dome light on, etc...) the battery will shut off and keep enough power to start your vehicle. You either just press the Restart button on your battery or if you have the Bluetooth controller you can do it from your Bluetooth app on your Android or Iphone.