In the practical limit case, the optical loss is improved by 0.1% absolute to the loss in our HJ-IBC cell by reducing the transmittance loss at the rear side, leading to a 0.15mAcm2 improvement in JSC. Similarly, the extrinsic recombination loss is reduced by 0.4% relative to our HJ-IBC cell, with extr at the maximum power point improved to 11.2ms ( const = 14.9ms, J 0 = 0.9 fA cm2) in the passivated sample from 5.6ms ( const = 8.8ms, J 0 = 3.0 fA cm2) in the HJ-IBC.