Hi I think the error code we get when we connect cells in parrallel is due to the simulated components. The simulated cell or battery is perfect. A battery consists of 2 or more cells connected either parrallel or series. The simulated cell does not have an internal resistance. Using a digital multimeter with high input impedance we actually measure the Emf (chemical properties). The internal resistance of fresh cell is low. Limits to 0. Ohms law states I=(V÷R) Amp. The software cannot devide by "0".