Lithium-ion batteries were made of LMO and NMC cathode and graphite anode.Cycling life was tested.The cause of battery capacity loss was studied by means of XRD,SEM and ICP-OES.The results shown that with the increase of cycling,the pole piece had dropped and peeled.Mn in LMO had dissoluted.Ni and Co in NMC had also dissoluted.These changes of blended positive electrode may be the main cause of capacity loss during cycling test.The quality control suggestions of the blended positive electrode were proposed according to above reasons.
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