Electrochemical studies of Mg-doped Li{sub 4}Ti{sub 5}O{sub 12} anodes.

Conference · Mon Jul 19 04:00:00 EDT 1999

OSTI ID:11899

Chen, C H; Jansen, A N; Vaughey, J

Commercial lithium-ion batteries use carbon as the material of choice for the anode. However, because lithiated carbon has a voltage very close to the potential of metallic lithium, there are concerns about the safety of fully-charged carbon electrodes. The safety issue can be addressed by using a material that intercalates lithium at a higher voltage. A promising material is the lithium-titanium-oxide spinel material Li{sub 4}Ti{sub 5}O{sub 12} which can accommodate 3 Li{sup +} ions per formula unit (corresponding to 175 mAh/g) in a two-phase reaction at approximately 1.5 V versus lithium. One of the drawbacks of this system is that the end-member Li{sub 4}Ti{sub 5}O{sub 12} is electronically insulating, which limits electron transfer at the electrode surface. By doping this material with magnesium, Li{sub 4{minus}x}Mg{sub x}Ti{sub 5}O{sub 12}, we introduced mixed-valent Ti{sup 4+}/Ti{sup 3+} into the stoichiometric spinel structure and thereby increased the electronic conductivity by several orders of magnitude without sacrificing electrochemical performance. In this presentation we will provide data on the extent of the solid solution in Li{sub 4{minus}x}Mg{sub x}Ti{sub 5}O{sub 12}, the variation of electronic conductivity as a function of dopant concentration and the rate capability of the doped material.

• Research Organization: Argonne National Lab., IL (US)
• Sponsoring Organization: US Department of Energy (US)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 11899
• Report Number(s): ANL/CMT/CP-99598
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
36 MATERIALS SCIENCE
ANODES
CLATHRATES
DOPED MATERIALS
ELECTRIC CONDUCTIVITY
ELECTRON TRANSFER
LITHIUM OXIDES
MAGNESIUM OXIDES
METAL-NONMETAL BATTERIES
PERFORMANCE
SPINELS
TITANIUM OXIDES