Characterization of commercial Li-ion batteries using electrochemical-calorimetric measurements

摘要: Abstract Commercial Li-ion cells of Type 18650 dimensions and prismatic designs from different manufacturers have been tested to evaluate their performance study thermal behavior using electrochemical–calorimetric methods. All in this work showed good cyclability under normal operating conditions. The measured heat effect for the were exothermic during discharge partially endothermic charge. Cell impedance was selected some dependence on state charge or depth discharge, with significant increase at end due concentration polarization. entropy coefficient (d E eq /d T ) A&T (18650) Panasonic (CGR 18650) potentiometric methods depths (DOD). values both DOD perturbation near 4.0 V, where d cell had an unexpected positive value. This found be consistent =4.0 V. may related a phase change LiCoO 2 cathode material, as reported literature, structural transformation graphite used anode cell.