Tremendous　poly(ethylene　terephthalate)　(PET)　plastics　has　been　abandoned　into　the　environment　as　rubbish,　which　is　inert　and　accumulated　in　the　ecosystem　across　the　globe.　In　the　present　work,　PET　plastics　are　changed　into　PET　particles　through　a　sample　low　temperature　solvothermal　treatment,　which　is　applied　as　anode　material　of　lithium　ion　battery.　The　redox　peaks　in　the　positive　and　negative　scanning　of　CV　(Cyclic　Voltammetry)　are　0.9　and　1.1　V,　respectively,　and　the　reversible　capacity　is　about　200　mAh/g　at　current　density　of　100　mA/g.　The　DFT　(Density　Functional　Theory)　calculation　results　shows　that　the　inserted　lithium　ion　is　coordinated　with　two　oxygen　ions,　which　are　on　the　two　neighboring　chains,　respectively,　and　per　formula　of　PET　(C10H8O4)　could　store　two　lithium　ions,　he.　the　theoretical　capacity　is　279　mAh/g.　The　calculated　redox　potential　is　also　consistent　with　the　experimental　results.　The　ex　situ　XRD　(X-ray　Diffraction),　FTIR　(Fourier　transform　infrared)　and　XPS　(X-ray　photoelectron　spectroscopy)　measurement　results　in　the　charge/discharge　are　consistent　with　DFT　calculation　results,　and　confirm　that　demonstrate　that　the　polymer＇s　lithiation/delithiation　process　is　revisable.　The　present　work　provides　a　novel　way　to　utilize　the　PET　plastics　waste.　Significance:　Innumerable　PET　plastics　have　been　abandoned,　which　is　resistance　to　natural　degradation.　Here　the　PET　plastics　were　transformed　into　PET　particles　after　a　solvothermal　treatment,　of　which　the　size　was　in　the　range　from　several　microns　to　tens　of　microns.　The　PET　particles　were　tested　as　the　anode　material　of　Lithium　ion　battery,　and　its　reversible　capacity　is　about　200　mAh/g　at　100　mA/g.　The　energy　storage　mechanism　is　attributed　to　redox　reaction　between　the　inserted　lithium　ions　and　the　ester　groups　on　PET　chain,　which　is　confirmed　through　the　DFT　calculation　and　XRD,　FTIR　and　XPS　measurement　results.　This　is　the　first　report　for　PET　plastics　used　as　electrode　materials,　and　it　provides　a　new　way　to　utilize　the　PET　refuse.