Aging in 18650-type Li-ion cells examined with neutron diffraction, electrochemical analysis and physico-chemical modeling

•Aging in NMC/C cells compared by neutron diffraction and electrochemical analysis.•A physico-chemical aging model is developed and validated for aging contributions.•Capacity loss is mainly due to loss of cyclable lithium into SEI layer growth.•Model and neutron data agree on cathode stoichiometry shift of 0.08.•Model and neutron data agree on anode stoichiometry shift of about 0.19.