The best place to buy a D2 battery is here. The cells aren't "premium" and you wouldn't expect them to be at the price, but IMHO they are fair value. The easiest/quickest way to trash them is being hard on the throttle all the time.Also plan B were is the best place to buy a battery I'm located in Ireland
11 pin the ground wire is the last pin on the rightShow a pic of the BMS sense wire connector with the 10 or 11 small wires.