Commercialized passivated emitter and rear cell (PERC) silicon solar cells feature direct contact of metal with silicon, which leads to severe recombination loss and low open circuit voltage (Voc). To overcome the loss, the authors demonstrate a highly stable and thickness-tolerant dopant-free electron-selective contact consisting of a strontium fluoride/aluminium (SrF2/Al) stack. The inserting dielectric SrF2 layer can mitigate the Fermi-level pinning effect between the silicon substrate and the Al electrode. Besides, a comparatively small Ohmic contact resistivity of 2 mΩ·cm2 on lightly doped n-type c-Si can be achieved when using 4 nm of SrF2. Moreover, the formed contact within 9 nm SrF2 is stable for over 5000 hours in the air without encapsulation. Solar cells with this novel dopant-free electron-selective contact reach a power conversion efficiency (PCE) of 21.56%. The promising results and its stable nature, indicate its potential to serve as cost-efficient electron-selective contact for various optoelectronic devices.